Updated: 17 June 2020
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| Tropical Cyclones
[Index] | Tropical Cyclone AMOS : JTWC Advisories |
| Season 2015-2016 Summaries (Operational Data): [AU] [SIO] [SPAC] [SH] | |
| ---> Tropical Cyclone AMOS Track Map and Data |
WTPS21 PGTW 20160418 04:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
150 NM EITHER SIDE OF A LINE FROM 16.7S 176.9W TO 11.6S 175.5W
WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.
WINDS IN THE AREA ARE ESTIMATED TO BE 27 TO 32 KNOTS. METSAT
IMAGERY AT 180000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 16.1S 176.9W. THE SYSTEM IS MOVING EAST-NORTHEASTWARD AT 07
KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 17.4S
179.5E, IS NOW LOCATED NEAR 16.1S 176.9E, APPROXIMATELY 375 NM WEST-
SOUTHWEST OF PAGO PAGO, AMERICAN SAMOA. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY DEPICTS A CONSOLIDATING LOW LEVEL CIRCULATION
CENTER (LLCC) WITH LIMITED CENTRAL CONVECTION. A 162125Z AMSU-B
MICROWAVE IMAGE SHOWED A WELL DEFINED LLCC WITH THE ASSOCIATED
CONVECTION SHEARED JUST SOUTHEAST. A 162037Z ASCAT PASS FURTHER
ILLUSTRATED THE LLCC WITH 30 KNOT WINDS WRAPPING AROUND THE
SYMMETRIC LLCC AND ISOLATED 35 KNOT WINDS LOCATED WITHIN THE
CONVECTION TO THE SOUTHEAST. ENVIRONMENTAL ANALYSIS INDICATES A
MARGINAL BUT IMPROVING ENVIRONMENT WITH 15 TO 20 KNOT VERTICAL WIND
SHEAR AND STRONG POLEWARD DIVERGENCE. DYNAMIC MODEL GUIDANCE SHOWS
THE DISTURBANCE TRACKING NORTHEASTWARD INTO A LOW VWS ENVIRONMENT
WITH WEAK DEVELOPMENT. SEA SURFACE TEMPERATURES NEAR 30 CELSIUS ARE
CONDUCIVE FOR FURTHER DEVELOPMENT. MAXIMUM SUSTAINED SURFACE WINDS
ARE ESTIMATED AT 27 TO 32 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1000 MB. BASED ON THE CURRENT STRUCTURE AND
IMPROVING ENVIRONMENT, THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
190400Z.//
=========================================================================
WTPS21 PGTW 20160419 04:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
140 NM EITHER SIDE OF A LINE FROM 14.6S 175.8W TO 11.4S 177.7W
WITHIN THE NEXT 06 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.
WINDS IN THE AREA ARE ESTIMATED TO BE 25 TO 30 KNOTS. METSAT
IMAGERY AT 190000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 14.3S 175.9W. THE SYSTEM IS MOVING NORTH-NORTHWESTWARD AT 06
KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 16.1S
176.9E, IS NOW LOCATED NEAR 14.3S 175.9W, APPROXIMATELY 305 NM WEST
OF PAGO PAGO, AMERICAN SAMOA. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS A CONSOLIDATING LOW LEVEL CIRCULATION CENTER (LLCC)
WITH LIMITED CENTRAL CONVECTION. A 190251Z SSMI MICROWAVE IMAGE
SHOWS A WELL DEFINED LLCC WITH ASSOCIATED, LIMITED CONVECTION
WRAPPING ALONG THE SOUTHERN AND WESTERN PERIPHERIES. A 181800Z
PARTIAL WINDSAT PASS FURTHER SHOWS 20 TO 25 KNOT WINDS ALONG THE
WESTERN PERIPHERY OF THE LLCC. ENVIRONMENTAL ANALYSIS INDICATES A
MARGINAL, BUT IMPROVING, ENVIRONMENT WITH 10 TO 15 KNOT VERTICAL
WIND SHEAR (VWS) AND AN EASTWARD OUTFLOW CHANNEL ON THE POLEWARD
SIDE. DYNAMIC MODEL GUIDANCE SHOWS THE DISTURBANCE TRACKING
NORTHWESTWARD INTO A MARGINALLY BETTER VWS ENVIRONMENT WITH
CORRESPONDING SLOW CONSOLIDATION. SEA SURFACE TEMPERATURES NEAR 30
CELSIUS ARE CONDUCIVE FOR FURTHER DEVELOPMENT. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1002 MB. BASED ON THE CURRENT
STRUCTURE AND IMPROVING ENVIRONMENT, THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 6-24
HOURS REMAINS HIGH. THIS SUPERSEDES REF A.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
200400Z.//
=========================================================================
WTPS31 PGTW 20160420 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI//180351ZAPR2016//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.//
RMKS/
1. TROPICAL CYCLONE 20P (TWENTY) WARNING NR 001
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
200000Z --- NEAR 13.1S 178.2W
MOVEMENT PAST SIX HOURS - 285 DEGREES AT 10 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 13.1S 178.2W
---
FORECASTS:
12 HRS, VALID AT:
201200Z --- 12.9S 179.0W
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 295 DEG/ 03 KTS
---
24 HRS, VALID AT:
210000Z --- 12.6S 179.6W
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 060 DEG/ 04 KTS
---
36 HRS, VALID AT:
211200Z --- 12.2S 178.9W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 080 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
220000Z --- 12.0S 177.6W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 015 NM NORTHEAST QUADRANT
015 NM SOUTHEAST QUADRANT
015 NM SOUTHWEST QUADRANT
015 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 100 DEG/ 06 KTS
---
72 HRS, VALID AT:
230000Z --- 12.4S 175.2W
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 125 DEG/ 08 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
240000Z --- 14.2S 172.6W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 125 DEG/ 07 KTS
---
120 HRS, VALID AT:
250000Z --- 15.8S 170.1W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
200300Z POSITION NEAR 13.0S 178.4W. TROPICAL CYCLONE 20P (TWENTY),
LOCATED APPROXIMATELY 316 NM WEST OF AVATA SAMOA, HAS TRACKED WEST-
NORTHWESTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY DEPICTS DEEP CONVECTION
CONSOLIDATING AROUND A LOW-LEVEL CIRCULATION CENTER (LLCC) WHICH IS
CURRENTLY COVERED BY A CENTRAL DENSE OVERCAST (CDO). A 192043Z AMSU-
B 89GHZ IMAGE SHOWS THAT THE DEEP CONVECTION IS RESTRICTED TO THE
NORTHEASTERN QUADRANT OF THE SYSTEM WITH SOME MODERATE CONVECTIVE
BANDS BEGINNING TO FORM TO THE SOUTHEAST OF THE LLCC. THE
CORRESPONDING 192043Z ASCAT-B PASS INDICATES BROAD AREAS OF 20-25
KNOT WINDS BOTH NORTH AND SOUTH OF THE LLCC, WHILE AN EARLIER
191747Z WINDSAT PASS SHOWED A FEW 30-35 KNOT UNFLAGGED PLOTS. THE
INITIAL INTENSITY IS ASSESSED AT 30 KNOTS BASED ON DVORAK ESTIMATES
BETWEEN 30 AND 35 KNOTS FROM KNES AND PGTW RESPECTIVELY. UPPER-LEVEL
ANALYSIS INDICATES TC 20P IS CURRENTLY IN A MARGINALLY FAVORABLE
ENVIRONMENT WITH LOW-MODERATE (10 TO 20 KNOTS) VERTICAL WIND SHEAR
(VWS), MODERATE POLEWARD OUTFLOW AND SEA SURFACE TEMPERATURES (SSTS)
OF 30 DEG CELSIUS. TC 18P IS CURRENTLY TRACKING WEST-NORTHWESTWARD
UNDER THE INFLUENCE A TRANSIENT RIDGE TO THE SOUTH. BY TAU 24, THIS
RIDGE WILL WEAKEN AND SHIFT EASTWARD, ALLOWING THE NEAR EQUATORIAL
RIDGE (NER) TO BECOME THE DOMINATE STEERING MECHANISM, RESULTING IN
A TURN OF TC 20P BACK TO AN EASTWARD TRACK BY TAU 36. THROUGH THE
REMAINDER OF THE FORECAST PERIOD THE SYSTEM IS FORECAST TO TRACK
EAST THEN SOUTHEASTWARD UNDER THE INFLUENCE OF THE NER. TC 20P IS
FORECAST TO SLOWLY INTENSIFY OVER THE NEXT 24 HOURS, AS THE UPPER-
LEVEL ENVIRONMENT REMAINS MARGINAL DUE TO MODERATE VWS AND THE
ENTRAINMENT OF RELATIVELY DRY AIR FROM THE WEST. AFTER TAU 24, THE
MOISTURE ENVELOPE WILL IMPROVE, VWS WILL DECREASE AND OUTFLOW WILL
IMPROVE AS THE SYSTEM TAPS INTO THE UPPER-LEVEL WESTERLIES, ALLOWING
FURTHER INTENSIFICATION, BEFORE PEAKING AT 60 KNOTS BY TAU 72.
THROUGH THE REMAINDER OF THE FORECAST PERIOD, TC 20P WILL SLOWLY
WEAKEN AS IT ENCOUNTERS HIGHER VWS. DYNAMIC MODEL GUIDANCE IS IN
FAIRLY TIGHT AGREEMENT IN THE OVERALL TRACK BUT THERE IS HIGH
UNCERTAINTY IN THE TIMING AND LOCATION OF THE TURN BACK TOWARDS THE
EAST, THEREFORE, THERE IS LOW CONFIDENCE IN THE JTWC FORECAST TRACK.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 200000Z IS 8 FEET. NEXT WARNINGS
AT 200900Z, 201500Z, 202100Z AND 210300Z. THIS CANCELS AND
SUPERSEDES REF A (WTPS22 PGTW 190400).//
=========================================================================
WTPS31 PGTW 20160420 09:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (TWENTY) WARNING NR 002//
RMKS/
1. TROPICAL CYCLONE 20P (TWENTY) WARNING NR 002
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
200600Z --- NEAR 12.9S 178.8W
MOVEMENT PAST SIX HOURS - 290 DEGREES AT 06 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 12.9S 178.8W
---
FORECASTS:
12 HRS, VALID AT:
201800Z --- 12.9S 179.3W
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 270 DEG/ 01 KTS
---
24 HRS, VALID AT:
210600Z --- 12.9S 179.5W
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 060 DEG/ 04 KTS
---
36 HRS, VALID AT:
211800Z --- 12.5S 178.8W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 075 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
220600Z --- 12.2S 177.7W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 110 DEG/ 07 KTS
---
72 HRS, VALID AT:
230600Z --- 13.0S 175.1W
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 130 DEG/ 06 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
240600Z --- 14.6S 173.0W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 140 DEG/ 06 KTS
---
120 HRS, VALID AT:
250600Z --- 16.3S 171.4W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
200900Z POSITION NEAR 12.9S 178.9W.
TROPICAL CYCLONE 20P (TWENTY), LOCATED APPROXIMATELY 352 NM WEST
OF AVATA SAMOA, HAS TRACKED WEST-NORTHWESTWARD AT 06 KNOTS OVER
THE PAST SIX HOURS. THE CURRENT POSITION IS BASED ON RECENT FIXES
FROM MULTIPLE REPORTING AGENCIES AND A 200414Z SSMIS PASS. THE
INTENSITY ESTIMATE OF 35 KNOTS IS CONSISTENT WITH RECENT SUBJECTIVE
DVORAK VALUES. TC 20P HAS BECOME A BIT MORE ORGANIZED OVER THE PAST
SIX HOURS, WITH DEEP CONVECTION FLARING OVER THE WESTERN PORTION OF
THE LOW LEVEL CIRCULATION CENTER. THE CYCLONE IS TRACKING ALONG THE
NORTHERN PERIPHERY OF A NARROW SUBTROPICAL STEERING RIDGE TO THE
SOUTH. DURING THE NEXT 24 HOURS, THE STEERING INFLUENCE OF THE
SUBTROPICAL RIDGE IS EXPECTED TO WANE AS NEAR-EQUATORIAL RIDGING
BUILDS TO THE NORTHEAST OF TC 20P. THE SYSTEM WILL TRACK SLOWLY IN
THE NEAR TERM AS THE PRIMARY STEERING INFLUENCE SWITCHES TO THE NEAR-
EQUATORIAL RIDGE. BY TAU 36 THE SYSTEM IS EXPECTED TO ACCELERATE
EASTWARD AND GRADUALLY SOUTHEASTWARD THROUGH THE EXTENDED RANGE AS A
MID-LATITUDE TROUGH APPROACHES FROM THE SOUTHWEST. GRADUAL
INTENSIFICATION SHOULD OCCUR THROUGH TAU 72 AS THE LOW LEVEL
CIRCULATION CONSOLIDATES AND POLEWARD OUTFLOW IMPROVES. WEAKENING IS
ANTICIPATED AFTER TAU 72 AS VERTICAL WIND SHEAR INCREASES AHEAD OF
THE APPROACHING MID-LATITUDE TROUGH. NUMERICAL MODELS ARE IN GOOD
AGREEMENT REGARDING THE OVERALL STEERING SCENARIO, BUT THERE IS
SIGNIFICANT UNCERTAINTY IN THE TRACK DIRECTION OVER THE NEXT SEVERAL
DAYS. THE CURRENT FORECAST HAS SHIFTED A BIT SOUTHWARD AND WESTWARD
TO INCREASE CONSISTENCY WITH THE MULTI-MODEL CONSENSUS AND MAJORITY
OF THE TRACK FORECAST GUIDANCE, WHICH DEPICT A TIGHTER TURN IN THE
MEDIUM TO EXTENDED RANGE THAN THE PREVIOUS FORECAST. GIVEN NOTED
UNCERTAINTY, THERE IS LOW CONFIDENCE IN THE TRACK FORECAST. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 200600Z IS 12 FEET. NEXT WARNINGS AT
202100Z, 210300Z, 210900Z, AND 211500Z.//
=========================================================================
WTPS31 PGTW 20160420 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 003//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 003
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
201200Z --- NEAR 12.8S 178.8W
MOVEMENT PAST SIX HOURS - 290 DEGREES AT 03 KTS
POSITION ACCURATE TO WITHIN 045 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 12.8S 178.8W
---
FORECASTS:
12 HRS, VALID AT:
210000Z --- 12.8S 179.1W
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 045 DEG/ 01 KTS
---
24 HRS, VALID AT:
211200Z --- 12.6S 178.9W
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 070 DEG/ 04 KTS
---
36 HRS, VALID AT:
220000Z --- 12.3S 178.1W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 090 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
221200Z --- 12.3S 176.8W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 115 DEG/ 06 KTS
---
72 HRS, VALID AT:
231200Z --- 13.3S 174.6W
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 130 DEG/ 06 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
241200Z --- 14.8S 172.8W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 140 DEG/ 06 KTS
---
120 HRS, VALID AT:
251200Z --- 16.5S 171.3W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
201500Z POSITION NEAR 12.8S 178.9W.
TROPICAL CYCLONE 20P (AMOS), LOCATED APPROXIMATELY 353 NM WEST OF
AVATA SAMOA, HAS TRACKED WEST-NORTHWESTWARD AT 03 KNOTS OVER THE
PAST SIX HOURS. THE CURRENT POSITION IS BASED ON RECENT FIXES FROM
MULTIPLE REPORTING AGENCIES AND A 200917Z ASCAT PASS. ADDITIONALLY,
THE PREVIOUS STORM POSITION HAS BEEN ADJUSTED SLIGHTLY TO THE EAST
BASED ON A REASSESSMENT OF AVAILABLE MICROWAVE SATELLITE IMAGERY.
THE CURRENT INTENSITY ESTIMATE OF 35 KNOTS IS CONSISTENT WITH RECENT
SUBJECTIVE DVORAK VALUES. TC 20P HAS SLOWED AS THE PRIMARY STEERING
MECHANISM BEGINS TO SWITCH FROM A WEAKENING SUBTROPICAL RIDGE TO
SOUTH TO A BUILDING NEAR-EQUATORIAL RIDGE TO THE NORTH. THE CYCLONE
IS EXPECTED TO REMAIN IN A WEAK STEERING ENVIRONMENT FOR THE NEXT 24
HOURS OR SO BEFORE THE NEAR-EQUATORIAL RIDGE BUILDS SUFFICIENTLY TO
CARRY THE SYSTEM EASTWARD AND GRADUALLY SOUTHEASTWARD THROUGH THE
EXTENDED RANGE AHEAD OF A DEVELOPING MID-LATITUDE TROUGH. SLOW
INTENSIFICATION SHOULD OCCUR THROUGH TAU 72 AS THE LOW LEVEL
CIRCULATION CONTINUES TO CONSOLIDATE AND POLEWARD OUTFLOW IMPROVES.
WEAKENING IS ANTICIPATED AFTER TAU 72 AS VERTICAL WIND SHEAR
INCREASES AHEAD OF THE APPROACHING MID-LATITUDE TROUGH. NUMERICAL
MODELS ARE IN GOOD AGREEMENT REGARDING THE GENERAL TRACK SCENARIO,
BUT THERE IS SIGNIFICANT UNCERTAINTY IN THE TRACK DIRECTION OVER THE
NEXT SEVERAL DAYS. THE CURRENT TRACK FORECAST LIES NEAR TO THE MULTI-
MODEL CONSENSUS AND MAJORITY OF THE TRACK FORECAST GUIDANCE. GIVEN
NOTED UNCERTAINTY, THERE IS LOW CONFIDENCE IN THE TRACK FORECAST.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 201200Z IS 12 FEET. NEXT WARNINGS
AT 202100Z, 210300Z, 210900Z AND 211500Z.//
=========================================================================
WTPS31 PGTW 20160420 21:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 004//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 004
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
201800Z --- NEAR 12.6S 179.6W
MOVEMENT PAST SIX HOURS - 285 DEGREES AT 08 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
REPEAT POSIT: 12.6S 179.6W
---
FORECASTS:
12 HRS, VALID AT:
210600Z --- 12.5S 179.3W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 080 DEG/ 03 KTS
---
24 HRS, VALID AT:
211800Z --- 12.4S 178.7W
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 085 DEG/ 07 KTS
---
36 HRS, VALID AT:
220600Z --- 12.3S 177.3W
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 100 DEG/ 07 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
221800Z --- 12.5S 175.9W
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 125 DEG/ 06 KTS
---
72 HRS, VALID AT:
231800Z --- 13.9S 173.8W
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 135 DEG/ 05 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
241800Z --- 15.4S 172.3W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 155 DEG/ 06 KTS
---
120 HRS, VALID AT:
251800Z --- 17.7S 171.2W
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
202100Z POSITION NEAR 12.6S 179.5W.
TROPICAL CYCLONE 20P (AMOS), LOCATED APPROXIMATELY 529 NM WEST OF
PAGO PAGO, HAS TRACKED WEST-NORTHWESTWARD AT 08 KNOTS OVER THE
PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A
BROAD AREA OF DENSE OVERCAST JUST TO THE NORTHWEST OF THE LOW LEVEL
CIRCULATION CENTER (LLCC). SATELLITE IMAGERY ALSO SHOWS IMPROVED
CONSOLIDATION AND TIGHTER BANDING OVER THE LAST SIX HOURS. A
201813Z SSMIS MICROWAVE IMAGE CONFIRMS A TIGHTENING LLCC AND GIVES
HIGH CONFIDENCE TO THE INITIAL POSITION. THE CURRENT INTENSITY IS
ASSESSED AT 40 KNOTS AND IS CONSISTENT WITH RECENT SUBJECTIVE DVORAK
ESTIMATES FROM ALL AGENCIES. SEA SURFACE TEMPERATURES ARE FAVORABLY
WARM, AND THERE IS A STRONG POLEWARD OUTFLOW CHANNEL SUPPORTING
DEVELOPMENT. HOWEVER, AN UPPER-LEVEL POINT SOURCE IS POSITIONED TO
THE NORTHEAST AND CONTRIBUTING TO SOME CONVERGENCE ALOFT WHICH IS
CURRENTLY LIMITING THE RATE OF INTENSIFICATION. TC AMOS IS CURRENTLY
SLOWING DUE TO A TRANSITION IN THE STEERING ENVIRONMENT AS A NEAR-
EQUATORIAL RIDGE IS BUILDING TO THE NORTHEAST. OVER THE NEXT 12 TO
24 HOURS THIS RIDGE WILL BUILD SUFFICIENTLY TO SHIFT THE TRACK
SOUTHEASTWARD, AND TC AMOS IS EXPECTED TO INTENSIFY. BEYOND TAU 48
VERTICAL WIND SHEAR IS EXPECTED TO INCREASE AS A MID-LATITUDE TROUGH
MOVES IN FROM THE SOUTH WEST. DYNAMIC MODEL GUIDANCE IS IN GOOD
AGREEMENT WITH THE FORECAST TRACK SCENARIO, BUT THERE EXISTS
SIGNIFICANT UNCERTAINTY BETWEEN MODELS IN THE TRACK DIRECTION IN THE
EXTENDED FORECAST. THE CURRENT FORECAST TRACK LIES NEAR THE MULTI-
MODEL CONSENSUS AND MAJORITY OF THE TRACK FORECAST GUIDANCE. GIVEN
THE UNCERTAINTY, THERE IS LITTLE CONFIDENCE IN THE FORECAST TRACK.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 201800Z IS 14 FEET. NEXT
WARNINGS AT 210300Z, 210900Z, 211500Z AND 212100Z.
=========================================================================
WTPS31 PGTW 20160421 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 005//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 005
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
210000Z --- NEAR 12.5S 179.5W
MOVEMENT PAST SIX HOURS - 045 DEGREES AT 01 KTS
POSITION ACCURATE TO WITHIN 025 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
REPEAT POSIT: 12.5S 179.5W
---
FORECASTS:
12 HRS, VALID AT:
211200Z --- 12.4S 179.0W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 085 DEG/ 05 KTS
---
24 HRS, VALID AT:
220000Z --- 12.3S 178.0W
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 085 DEG/ 06 KTS
---
36 HRS, VALID AT:
221200Z --- 12.2S 176.7W
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 110 DEG/ 10 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
230000Z --- 12.9S 174.8W
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 130 DEG/ 07 KTS
---
72 HRS, VALID AT:
240000Z --- 14.7S 172.4W
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 140 DEG/ 06 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
250000Z --- 16.6S 170.6W
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 140 DEG/ 06 KTS
---
120 HRS, VALID AT:
260000Z --- 18.5S 168.9W
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
210300Z POSITION NEAR 12.5S 179.4W.
TROPICAL CYCLONE (TC) 20P (AMOS), LOCATED APPROXIMATELY 525 NM WEST
OF PAGO PAGO, AMERICAN SAMOA, HAS TRACKED NORTHEASTWARD AT 01 KNOT
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
(MSI) SHOWS A CONSOLIDATING SYSTEM WITH A BROAD CENTRAL DENSE
OVERCAST OBSCURING THE LOW LEVEL CIRCULATION CENTER THAT APPEARS TO
BE STATIONARY. THE INITIAL POSITION IS BASED ON THE MSI LOOP WITH LOW
CONFIDENCE. THE INITIAL INTENSITY IS BASED ON AN OVERALL ASSESSMENT
OF DVORAK ESTIMATES FROM ALL REPORTING AGENCIES. UPPER LEVEL ANALYSIS
INDICATES TC 20P IS IN AN AREA OF LIGHT VERTICAL WIND SHEAR (VWS) AND
STRONG POLEWARD OUTFLOW. HOWEVER, AN INDUCED TROUGH TO THE NORTHEAST
IS CAUSING SUBSIDENCE ALONG THE NORTHEAST QUADRANT AND INHIBITING
SIGNIFICANT DEVELOPMENT. TC AMOS HAS BECOME QUASI-STATIONARY (QS) AS
IT TRANSITIONS INTO A NEW STEERING MECHANISM - A NEAR EQUATORIAL
RIDGE (NER) BUILDING IN FROM THE NORTHEAST. THE NER WILL SLOWLY
NUDGE THE TC EASTWARD OVER THE NEXT 12-36 HOURS THEN SOUTHEASTWARD AT
A FASTER RATE. THE CYCLONE IS EXPECTED TO SLOWLY INTENSIFY, PEAKING
AT 85 KNOTS NEAR TAU 48 BEFORE GRADUALLY WEAKENING DUE TO INCREASING
VWS AS IT MOVES MORE POLEWARD. DYNAMIC MODEL GUIDANCE IS IN GOOD
AGREEMENT WITH THE FORECAST TRACK SCENARIO, HOWEVER, DUE TO THE
UNCERTAINTY CAUSED BY THE QS MOTION IN THE INITIAL PHASE, THERE IS
OVERALL LOW CONFIDENCE IN THE JTWC FORECAST TRACK. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 210000Z IS 15 FEET. NEXT WARNINGS AT
211500Z AND 220300Z.//
=========================================================================
WTPS31 PGTW 20160421 09:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 006//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 006
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
210600Z --- NEAR 13.0S 179.3W
MOVEMENT PAST SIX HOURS - 125 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
REPEAT POSIT: 13.0S 179.3W
---
FORECASTS:
12 HRS, VALID AT:
211800Z --- 13.0S 178.3W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 090 DEG/ 06 KTS
---
24 HRS, VALID AT:
220600Z --- 13.0S 177.0W
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 105 DEG/ 07 KTS
---
36 HRS, VALID AT:
221800Z --- 13.3S 175.6W
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 115 DEG/ 08 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
230600Z --- 13.9S 174.1W
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 120 DEG/ 07 KTS
---
72 HRS, VALID AT:
240600Z --- 15.1S 171.7W
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 125 DEG/ 06 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
250600Z --- 16.4S 169.7W
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 130 DEG/ 06 KTS
---
120 HRS, VALID AT:
260600Z --- 17.9S 167.7W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
210900Z POSITION NEAR 13.0S 179.0W.
TROPICAL CYCLONE (TC) 20P (AMOS), LOCATED APPROXIMATELY 507 NM WEST
OF PAGO PAGO, AMERICAN SAMOA, HAS TRACKED SOUTHEASTWARD AT 04 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
DEPICTS A SLOWLY CONSOLIDATING LOW-LEVEL CIRCULATION CENTER WITH
CYCLING DEEP CONVECTION OBSCURING A RAGGED BUT DEFINED CENTER.
DESPITE THE UNIMPRESSIVE DEEP CONVECTIVE STRUCTURE, A 210603Z
WINDSAT COMPOSITE 37GHZ COLOR IMAGE DEPICTS A WELL-DEFINED MICROWAVE
EYE FEATURE SURROUNDED BY A CYAN RING WITH MULTIPLE CONVECTIVE
BANDING WRAPPING INTO THE CENTER. THIS EXCELLENT LOW-LEVEL
STRUCTURE, IN COMBINATION WITH THE RADIAL OUTFLOW, SUGGESTS AN
IMMINENT RAPID INTENSIFICATION PHASE. THE CURRENT INTENSITY IS
ASSESSED AT 45 KNOTS BASED ON DVORAK INTENSITY ESTIMATES OF T3.0 (45
KNOTS)--HOWEVER, THE MICROWAVE HINTS AT A SLIGHTLY HIGHER INTENSITY
OF 50 TO PERHAPS 55 KNOTS. TC 20P HAS TURNED SOUTHEASTWARD AND IS
FORECAST TO ACCELERATE EASTWARD TO SOUTHEASTWARD AS IT TRACKS ALONG
THE PERIPHERY OF THE NEAR-EQUATORIAL STEERING RIDGE. OVERALL,
DYNAMIC GUIDANCE IS IN GOOD AGREEMENT AND SUPPORTS THE JTWC FORECAST
TRACK WITH HIGH CONFIDENCE. AS PREVIOUSLY MENTIONED, ENVIRONMENTAL
CONDITIONS ARE FAVORABLE THEREFORE TC 20P IS EXPECTED TO RAPIDLY
INTENSIFY TO A PEAK INTENSITY OF 95 KNOTS BY TAU 48. AFTER TAU 72,
THE SYSTEM SHOULD WEAKEN AS IT BEGINS TO ENCOUNTER INCREASING
WESTERLY FLOW. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 210600Z IS 15
FEET. NEXT WARNINGS AT 211500Z, 212100Z, 220300Z AND 220900Z.//
=========================================================================
WTPS31 PGTW 20160421 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 007//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 007
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
211200Z --- NEAR 12.7S 178.9W
MOVEMENT PAST SIX HOURS - 090 DEGREES AT 03 KTS
POSITION ACCURATE TO WITHIN 045 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
REPEAT POSIT: 12.7S 178.9W
---
FORECASTS:
12 HRS, VALID AT:
220000Z --- 12.6S 177.7W
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 100 DEG/ 06 KTS
---
24 HRS, VALID AT:
221200Z --- 12.8S 176.4W
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 105 DEG/ 07 KTS
---
36 HRS, VALID AT:
230000Z --- 13.2S 175.0W
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 115 DEG/ 07 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
231200Z --- 13.8S 173.6W
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 120 DEG/ 06 KTS
---
72 HRS, VALID AT:
241200Z --- 15.0S 171.3W
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 125 DEG/ 06 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
251200Z --- 16.4S 169.3W
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 130 DEG/ 06 KTS
---
120 HRS, VALID AT:
261200Z --- 17.9S 167.3W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
211500Z POSITION NEAR 12.7S 178.6W.
TROPICAL CYCLONE (TC) 20P (AMOS), LOCATED APPROXIMATELY 488 NM WEST
OF PAGO PAGO, AMERICAN SAMOA, HAS TRACKED EASTWARD AT 03 KNOTS OVER
THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY
DEPICTS A COMPACT, CONSOLIDATING LOW-LEVEL CIRCULATION CENTER WITH
IMPROVED CONVECTIVE STRUCTURE EVIDENT IN A 210702Z SSMIS 91GHZ IMAGE
AND A 210603Z WINDSAT COMPOSITE 37GHZ COLOR IMAGE. THE WINDSAT 37GHZ
COLOR IMAGE DEPICTS A WELL-DEFINED MICROWAVE EYE FEATURE SURROUNDED
BY A CYAN RING WITH MULTIPLE CONVECTIVE BANDING WRAPPING INTO THE
CENTER. THIS EXCELLENT LOW-LEVEL STRUCTURE, IN COMBINATION WITH THE
RADIAL OUTFLOW, SUGGESTS AN IMMINENT RAPID INTENSIFICATION PHASE.
THE CURRENT INTENSITY IS ASSESSED AT 55 KNOTS BASED ON DVORAK
INTENSITY ESTIMATES OF T3.5 (55 KNOTS). TC 20P HAS TRACKED SLOWLY
EASTWARD AND IS FORECAST TO ACCELERATE EASTWARD TO SOUTHEASTWARD AS
IT TRACKS ALONG THE PERIPHERY OF THE NEAR-EQUATORIAL STEERING RIDGE.
OVERALL, DYNAMIC GUIDANCE IS IN TIGHT AGREEMENT AND SUPPORTS THE
JTWC FORECAST TRACK WITH HIGH CONFIDENCE. AS PREVIOUSLY MENTIONED,
ENVIRONMENTAL CONDITIONS ARE FAVORABLE THEREFORE TC 20P IS EXPECTED
TO RAPIDLY INTENSIFY TO A PEAK INTENSITY OF 95 KNOTS BY TAU 48.
AFTER TAU 72, THE SYSTEM SHOULD WEAKEN AS IT BEGINS TO ENCOUNTER
INCREASING WESTERLY FLOW. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 211200Z
IS 18 FEET. NEXT WARNINGS AT 212100Z, 220300Z, 220900Z AND 221500Z.//
=========================================================================
WTPS31 PGTW 20160421 21:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 008
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
211800Z --- NEAR 12.7S 178.3W
MOVEMENT PAST SIX HOURS - 090 DEGREES AT 06 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
REPEAT POSIT: 12.7S 178.3W
---
FORECASTS:
12 HRS, VALID AT:
220600Z --- 12.6S 176.9W
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 105 DEG/ 07 KTS
---
24 HRS, VALID AT:
221800Z --- 12.9S 175.5W
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 105 DEG/ 07 KTS
---
36 HRS, VALID AT:
230600Z --- 13.3S 174.1W
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 120 DEG/ 07 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
231800Z --- 14.0S 172.8W
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 125 DEG/ 05 KTS
---
72 HRS, VALID AT:
241800Z --- 15.3S 171.0W
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 135 DEG/ 05 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
251800Z --- 16.6S 169.7W
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 125 DEG/ 06 KTS
---
120 HRS, VALID AT:
261800Z --- 17.9S 167.7W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
212100Z POSITION NEAR 12.7S 177.9W.
TROPICAL CYCLONE 20P (AMOS), LOCATED APPROXIMATELY 454 NM WEST OF
PAGO PAGO, AMERICAN SAMOA, HAS TRACKED EASTWARD AT 06 KNOTS OVER THE
PAST SIX HOURS. ANIMATED ENHANCED INFRARED IMAGERY DEPICTS A SYSTEM
THAT HAS BECOME BETTER ORGANIZED OVER THE LAST SIX HOURS AND IS
DEVELOPING A DENSE OVERCAST OVER THE CENTER. RECENT MICROWAVE
IMAGERY SHOWS THAT CONVECTION HAS DEEPENED WITHIN BANDING FEATURES,
BUT ALSO SHOW SLIGHT DEFORMATION OF THE MICROWAVE EYE. THE CURRENT
POSITION IS BASED ON A 211800Z SSMIS 91GHZ IMAGE SHOWING THE
AFOREMENTIONED EYE FEATURE WITH MODERATE CONFIDENCE. THE INITIAL
INTENSITY IS ASSESSED AT 55 KNOTS AND IS BASED ON SUBJECTIVE DVORAK
ESTIMATES FROM ALL AGENCIES REPORTING T3.5 (55 KNOTS). TC AMOS IS
EXPECTED TO INTENSIFY OVER THE NEXT 36 HOURS REACHING A PEAK
INTENSITY OF 95 KNOTS AS IT TRAVELS EAST-SOUTHEASTWARD ALONG THE
SOUTHERN PERIPHERY OF A NEAR-EQUATORIAL RIDGE. BEYOND TAU 36, WIND
SHEAR IS EXPECTED TO INCREASE AS TC AMOS IS INFLUENCED BY A STRONG
SUBTROPICAL JET TO THE SOUTH. DYNAMIC MODEL GUIDANCE IS IN GOOD
AGREEMENT FOR THE FIRST 72 HOURS. BEYOND TAU 72 A MAJORITY OF MODELS
ARE GROUPED TIGHTLY AROUND THE MULTI-CONSENSUS MODEL TRACK, HOWEVER
BOTH THE ECMWF AND NAVGEM SOLUTIONS INDICATE THAT AN EXTENSION OF
THE STEERING RIDGE WILL DEVELOP. IN THIS SCENARIO TC AMOS WOULD
BRIEFLY SLOW DOWN AND TAKE A MORE SOUTHERLY TRACK. THE CURRENT
FORECAST TRACK IS BASED ON THE MULTI-MODEL CONSENSUS TRACK DUE TO
THE TIGHT GROUPING OF A MAJORITY OF ITS MEMBERS. DUE TO THE
UNCERTAINTY IN THE EXTENDED FORECAST THERE IS LOW CONFIDENCE IN THE
FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 211800Z IS 18
FEET. NEXT WARNINGS AT 220300Z, 220900Z, 221500Z AND 222100Z.
=========================================================================
WTPS31 PGTW 20160422 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 009//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 009
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
220000Z --- NEAR 12.4S 177.4W
MOVEMENT PAST SIX HOURS - 070 DEGREES AT 09 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
REPEAT POSIT: 12.4S 177.4W
---
FORECASTS:
12 HRS, VALID AT:
221200Z --- 12.5S 176.0W
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 110 DEG/ 07 KTS
---
24 HRS, VALID AT:
230000Z --- 12.9S 174.7W
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 115 DEG/ 07 KTS
---
36 HRS, VALID AT:
231200Z --- 13.5S 173.4W
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 120 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
240000Z --- 14.1S 172.4W
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 130 DEG/ 05 KTS
---
72 HRS, VALID AT:
250000Z --- 15.3S 171.0W
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 135 DEG/ 03 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
260000Z --- 16.2S 170.0W
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 130 DEG/ 04 KTS
---
120 HRS, VALID AT:
270000Z --- 17.4S 168.6W
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
220300Z POSITION NEAR 12.4S 177.1W.
TROPICAL CYCLONE (TC) 20P (AMOS), LOCATED APPROXIMATELY 407 NM
WEST-NORTHWEST OF PAGO PAGO, AMERICAN SAMOA, HAS TRACKED EAST-
NORTHEASTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS A SYSTEM THAT CONTINUES
TO CONSOLIDATE AS IT MAINTAINS A DEEP CENTRAL DENSE OVERCAST FEATURE
THAT IS COVERING THE LOW LEVEL CIRCULATION CENTER. THE INITIAL
POSITION IS BASED ON THE MSI LOOP AND EXTRAPOLATED FROM A 212143Z
BULLSEYE ASCAT PASS WITH FAIR CONFIDENCE. THE INITIAL INTENSITY IS
BASED ON CONGRUENT DVORAK ESTIMATES FROM PGTW, KNES, AND NFFN. UPPER
LEVEL ANALYSIS INDICATES TC 20P IS IN AN AREA OF LIGHT VERTICAL WIND
SHEAR (VWS) AND STRONG NEAR-RADIAL OUTFLOW WITH SOME SUBSIDENCE ALONG
THE NORTHEAST QUADRANT. TC AMOS IS EXPECTED TO INTENSIFY OVER THE
NEXT 36 HOURS PEAKING AT 105 KNOTS AS IT TRACKS EAST THEN
SOUTHEASTWARD ALONG THE SOUTHERN PERIPHERY OF A NEAR-EQUATORIAL RIDGE
(NER). AFTERWARDS, INCREASING VWS ASSOCIATED WITH THE PREVAILING
WESTERLIES WILL BEGIN TO ERODE THE SYSTEM. DYNAMIC MODEL GUIDANCE IS
IN GOOD AGREEMENT FOR THE FIRST 48 HOURS. BEYOND THAT, A GROUP OF
TRACKERS INCLUDING GFDN, NVGM, AND COTC INDICATE A MORE POLEWARD
TRACK, PRESUMABLY IN RESPONSE TO AN EXTENSION OF THE NER. DUE TO THE
UNCERTAINTY IN THE EXTENDED FORECAST THERE IS OVERALL LOW CONFIDENCE
IN THE JTWC FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
220000Z IS 20 FEET. NEXT WARNINGS AT 221500Z AND 230300Z.//
=========================================================================
WTPS31 PGTW 20160422 09:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 010
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
220600Z --- NEAR 12.5S 177.0W
MOVEMENT PAST SIX HOURS - 090 DEGREES AT 06 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
REPEAT POSIT: 12.5S 177.0W
---
FORECASTS:
12 HRS, VALID AT:
221800Z --- 12.7S 175.7W
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 110 DEG/ 07 KTS
---
24 HRS, VALID AT:
230600Z --- 13.1S 174.4W
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 115 DEG/ 07 KTS
---
36 HRS, VALID AT:
231800Z --- 13.7S 173.2W
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 135 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
240600Z --- 14.5S 172.4W
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 145 DEG/ 03 KTS
---
72 HRS, VALID AT:
250600Z --- 15.5S 171.7W
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 135 DEG/ 04 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
260600Z --- 16.6S 170.6W
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 120 DEG/ 05 KTS
---
120 HRS, VALID AT:
270600Z --- 17.6S 168.7W
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
220900Z POSITION NEAR 12.5S 176.7W.
TROPICAL CYCLONE (TC) 20P (AMOS), LOCATED APPROXIMATELY 383 NM WEST-
NORTHWEST OF PAGO PAGO, AMERICAN SAMOA, HAS TRACKED EASTWARD AT 06
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS A COMPACT, CONSOLIDATING LOW-LEVEL CIRCULATION
CENTER WITH A FORMATIVE EYE. A 220650Z SSMIS 91GHZ IMAGE SHOWS
TIGHTLY-CURVED BANDING WRAPPING INTO A MICROWAVE EYE FEATURE. TC 20P
HAS RAPIDLY INTENSIFIED OVER THE PAST 24 HOURS, INCREASING ABOUT 30
KNOTS FROM 45 KNOTS TO 75 KNOTS. THE CURRENT INTENSITY IS ASSESSED
AT 75 KNOTS BASED ON DVORAK INTENSITY ESTIMATES OF T4.5 (77 KNOTS)
FROM KNES AND PGTW. UPPER-LEVEL ANALYSIS INDICATES NEAR-RADIAL
OUTFLOW, WHICH SHOULD SUPPORT CONTINUED INTENSIFICATION OVER THE
NEXT 48 HOURS. TC 20P IS FORECAST TO TRACK EAST-SOUTHEASTWARD TO
SOUTHEASTWARD AS IT TRACKS ALONG THE PERIPHERY OF THE NEAR-
EQUATORIAL STEERING RIDGE. THIS TRACK WILL DRIVE THE SYSTEM ABOUT 80-
90 NM SOUTH OF PAGO PAGO WITH THE GALE-FORCE WINDS JUST SKIRTING
AMERICAN SAMOA. AFTER TAU 48, THE SYSTEM SHOULD TURN SOUTH-
SOUTHEASTWARD AS A WEAK EXTENSION OF THE STEERING RIDGE BUILDS TO
THE NORTHEAST. AFTER TAU 72, TC 20P WILL RESUME A MORE EASTWARD
TRAJECTORY AS IT BEGINS TO ENCOUNTER SUBTROPICAL WESTERLIES, WHICH
WILL PRODUCE A WEAKENING TREND. OVERALL, DYNAMIC GUIDANCE IS IN GOOD
AGREEMENT AND SUPPORTS THE JTWC FORECAST TRACK WITH HIGH CONFIDENCE.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 220600Z IS 24 FEET. NEXT WARNINGS
AT 221500Z, 222100Z, 230300Z AND 230900Z.//
=========================================================================
WTPS31 PGTW 20160422 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 011//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 011
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
221200Z --- NEAR 12.4S 176.3W
MOVEMENT PAST SIX HOURS - 090 DEGREES AT 08 KTS
POSITION ACCURATE TO WITHIN 030 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
REPEAT POSIT: 12.4S 176.3W
---
FORECASTS:
12 HRS, VALID AT:
230000Z --- 12.6S 175.0W
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 115 DEG/ 06 KTS
---
24 HRS, VALID AT:
231200Z --- 13.1S 173.8W
MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 125 DEG/ 06 KTS
---
36 HRS, VALID AT:
240000Z --- 13.8S 172.8W
MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 135 DEG/ 04 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
241200Z --- 14.4S 172.2W
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 145 DEG/ 03 KTS
---
72 HRS, VALID AT:
251200Z --- 15.5S 171.4W
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 130 DEG/ 04 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
261200Z --- 16.5S 170.1W
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 120 DEG/ 05 KTS
---
120 HRS, VALID AT:
271200Z --- 17.5S 168.2W
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
221500Z POSITION NEAR 12.5S 176.0W.
TROPICAL CYCLONE (TC) 20P (AMOS), LOCATED APPROXIMATELY 346 NM WEST-
NORTHWEST OF PAGO PAGO, AMERICAN SAMOA, HAS TRACKED EASTWARD AT 08
KNOTS OVER THE PAST SIX HOURS.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 221200Z IS 28 FEET. NEXT
WARNINGS AT 222100Z, 230300Z, 230900Z AND 231500Z.//
=========================================================================
WTPS31 PGTW 20160422 21:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 012//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 012
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
221800Z --- NEAR 12.4S 175.7W
MOVEMENT PAST SIX HOURS - 100 DEGREES AT 09 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
REPEAT POSIT: 12.4S 175.7W
---
FORECASTS:
12 HRS, VALID AT:
230600Z --- 12.7S 174.5W
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 115 DEG/ 07 KTS
---
24 HRS, VALID AT:
231800Z --- 13.3S 173.2W
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 125 DEG/ 05 KTS
---
36 HRS, VALID AT:
240600Z --- 13.9S 172.3W
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 145 DEG/ 04 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
241800Z --- 14.5S 171.9W
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 160 DEG/ 02 KTS
---
72 HRS, VALID AT:
251800Z --- 15.3S 171.6W
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 140 DEG/ 02 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
261800Z --- 16.0S 171.0W
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 120 DEG/ 07 KTS
---
120 HRS, VALID AT:
271800Z --- 17.3S 168.5W
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
222100Z POSITION NEAR 12.5S 175.4W.
TROPICAL CYCLONE 20P (AMOS), LOCATED APPROXIMATELY 313 NM WEST-
NORTHWEST OF PAGO PAGO, AMERICAN SAMOA HAS TRACKED EASTWARD AT 09
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED IMAGERY
DEPICTS STRONG FLARING CENTRAL CONVECTION WITH AN ASSOCIATED DENSE
OVERCAST LAYER OBSCURING THE LOW LEVEL CIRCULATION CENTER, GIVING
FAIR CONFIDENCE TO THE INITIAL POSITION. THE INITIAL INTENSITY IS
ASSESSED AT 90 KNOTS AND IS IN ALIGNMENT WITH SUBJECTIVE DVORAK
ESTIMATES FROM PGTW, NFFN AND KNES. CURRENTLY THE ENVIRONMENT IS
FAVORABLE FOR FURTHER DEVELOPMENT AS A STRONG POLEWARD OUTFLOW
EXISTS AND SEA SURFACE TEMPERATURES ARE WARM. UPPER-LEVEL
NORTHEASTERLY WINDS ARE PRESENT CREATING SOME SUBSIDENCE, BUT APPEAR
TO HAVE RELAXED SOME IN THE LAST SIX HOURS. TC AMOS IS EXPECTED TO
INTENSIFY IN THE NEXT 24 TO 36 HOURS REACHING A PEAK INTENSITY OF
110 KNOTS AS OUTFLOW AND VERTICAL WIND SHEAR CONDITIONS CONTINUE TO
IMPROVE. CURRENTLY TC AMOS IS TRAVELING EASTWARD ALONG THE SOUTHERN
BOUNDARY OF A NEAR-EQUATORIAL RIDGE. BY TAU 48 AN EXTENSION OF THE
STEERING RIDGE WILL DEVELOP, BRIEFLY SLOWING THE STORM AND SHIFTING
THE TRACK SLIGHTLY TO THE SOUTH. BEYOND TAU 48, VERTICAL WIND SHEAR
IS ALSO EXPECTED TO INCREASE AS TC AMOS APPROACHES SUBTROPICAL
WESTERLIES TO THE SOUTH. DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT
FOR THE FIRST 36 HOURS. BEYOND TAU 36 THERE IS A DEGREE OF
UNCERTAINTY TO THE POSITION AND DEPTH OF THE SOUTHWARD TURN AND IN
THE EXTENDED TRACK AS TC AMOS INTERACTS WITH THE SUBROPICAL
WESTERLIES. DUE TO THE MENTIONED UNCERTAINTY, THERE IS LOW
CONFIDENCE IN THE FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
221800Z IS 28 FEET. NEXT WARNINGS AT 230300Z, 230900Z, 231500Z AND
232100Z.
=========================================================================
WTPS31 PGTW 20160423 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 013//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 013
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
230000Z --- NEAR 12.4S 174.9W
MOVEMENT PAST SIX HOURS - 095 DEGREES AT 08 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT
015 NM SOUTHEAST QUADRANT
015 NM SOUTHWEST QUADRANT
015 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
REPEAT POSIT: 12.4S 174.9W
---
FORECASTS:
12 HRS, VALID AT:
231200Z --- 12.7S 173.5W
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT
015 NM SOUTHEAST QUADRANT
015 NM SOUTHWEST QUADRANT
015 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 120 DEG/ 06 KTS
---
24 HRS, VALID AT:
240000Z --- 13.3S 172.5W
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT
015 NM SOUTHEAST QUADRANT
015 NM SOUTHWEST QUADRANT
015 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 130 DEG/ 05 KTS
---
36 HRS, VALID AT:
241200Z --- 13.9S 171.8W
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 160 DEG/ 04 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
250000Z --- 14.7S 171.5W
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 160 DEG/ 02 KTS
---
72 HRS, VALID AT:
260000Z --- 15.3S 171.3W
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 130 DEG/ 05 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
270000Z --- 16.6S 169.6W
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 120 DEG/ 06 KTS
---
120 HRS, VALID AT:
280000Z --- 17.9S 167.4W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
230300Z POSITION NEAR 12.5S 174.6W. TROPICAL CYCLONE 20P (AMOS),
LOCATED APPROXIMATELY 270 NM WEST-NORTHWEST OF PAGO PAGO, HAS
TRACKED EASTWARD AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS CENTRAL DEEP
CONVECTION MAINTAINING A CENTRAL DENSE OVERCAST FEATURE THAT IS
MASKING THE LOW LEVEL CIRCULATION CENTER (LLCC). THE INITIAL
POSITION IS BASED ON THE MSI LOOP AND EXTRAPOLATED FROM A 222121Z
AMSU-B 89 GHZ MICROWAVE IMAGE SHOWING TIGHT CONVECTIVE BANDING INTO
A VERY COMPACT MICROWAVE CIRCULATION CENTER, GIVING FAIR CONFIDENCE
TO THE INITIAL POSITION. THE INITIAL INTENSITY IS ASSESSED AT 90
KNOTS BASED ON CONSISTENT SUBJECTIVE DVORAK ESTIMATES FROM PGTW,
KNES AND NFFN. UPPER LEVEL ANALYSIS INDICATES TC 20P IS CURRENTLY IN
AN AREA OF LIGHT (5-10 KNOTS) VERTICAL WIND SHEAR (VWS) WITH A
STRONG POLEWARD OUTFLOW CHANNEL, WITH SOME CONVERGENCE AND
SUBSIDENCE EVIDENT ON THE EASTERN SIDE OF THE SYSTEM SOMEWHAT
LIMITING THE OUTFLOW IN THAT QUADRANT. TC AMOS IS TRACKING OVER AN
AREA OF VERY WARM SEA SURFACE TEMPERATURES (SSTS) NEAR 30 DEG
CELSIUS, PROVIDING ADDITIONAL SUPPORT TO THE SYSTEM. TC AMOS IS
EXPECTED TO INTENSIFY OVER THE NEXT 24 HOURS REACHING A PEAK
INTENSITY OF 100 KNOTS AS OUTFLOW AND VERTICAL WIND SHEAR CONDITIONS
CONTINUE TO BE FAVORABLE AS IT TRACKS EAST-SOUTHEASTWARD ALONG THE
SOUTHERN PERIPHERY OF A NEAR-EQUATORIAL RIDGE (NER). AFTER TAU 36 AN
EXTENSION OF THE STEERING NER BUILDS IN ON THE SOUTHEASTERN
PERIPHERY OF THE STORM, SLOWING THE FORWARD MOTION AND TURNING THE
SYSTEM ONTO A MORE SOUTHERLY TRACK OVER UPOLU ISLAND, SAMOA. DUE TO
LAND INTERACTION WITH UPOLU, TC AMOS WILL WEAKEN SLIGHTLY BEFORE
EMERGING BACK OVER WATER ON THE SLOW SOUTHERLY TRACK. BY TAU 72, TC
AMOS WILL BEGIN TO INTERACT WITH THE UPPER-LEVEL WESTERLY FLOW AND
TRANSITION TO A SOUTHEASTWARD TRACK WHILE QUICKLY WEAKENING AS
INCREASING VWS AND DECREASING SSTS WILL ERODE THE SYSTEM. DYNAMIC
MODEL GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH TAU 48 WITH THE
MAJORITY OF AVAILABLE MODEL TRACKERS TIGHTLY CLUSTERED ABOUT THE
FORECAST TRACK, WITH INCREASING UNCERTAINTY REGARDING THE SPEED AND
TRACK IN THE LATER TAUS, RESULTING IN LOW CONFIDENCE IN THE JTWC
FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 230000Z IS 28
FEET. NEXT WARNINGS AT 230900Z, 231500Z, 232100Z AND 240300Z.//
=========================================================================
WTPS31 PGTW 20160423 09:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 014//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 014
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
230600Z --- NEAR 12.8S 173.2W
MOVEMENT PAST SIX HOURS - 105 DEGREES AT 15 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
REPEAT POSIT: 12.8S 173.2W
---
FORECASTS:
12 HRS, VALID AT:
231800Z --- 13.5S 171.7W
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 135 DEG/ 07 KTS
---
24 HRS, VALID AT:
240600Z --- 14.4S 170.7W
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 140 DEG/ 03 KTS
---
36 HRS, VALID AT:
241800Z --- 14.9S 170.3W
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 150 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
250600Z --- 15.4S 170.0W
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 145 DEG/ 02 KTS
---
72 HRS, VALID AT:
260600Z --- 16.0S 169.6W
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 130 DEG/ 03 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
270600Z --- 16.7S 168.7W
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 115 DEG/ 07 KTS
---
120 HRS, VALID AT:
280600Z --- 17.8S 166.0W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
230900Z POSITION NEAR 13.0S 172.8W.
TROPICAL CYCLONE 20P (AMOS), LOCATED APPROXIMATELY 171 NM WEST-
NORTHWEST OF PAGO PAGO, HAS TRACKED EAST-SOUTHEASTWARD AT 15 KNOTS
OVER THE PAST SIX HOURS. THE CURRENT POSITION IS BASED ON RECENT
MICROWAVE SATELLITE IMAGERY INCLUDING A 230528Z CORIOLIS AND A
230623Z SSMIS PASS. THE INTENSITY OF 90 KNOTS IS CONSISTENT WITH
SUBJECTIVE DVORAK INTENSITY ESTIMATES FROM MULTIPLE REPORTING
AGENCIES. TC 20P HAS ACCELERATED EAST-SOUTHEASTWARD OVER THE PAST
SIX HOURS UNDER THE STEERING INFLUENCE OF A NEAR-EQUATORIAL RIDGE TO
THE NORTH AND EAST. THIS RECENT CHANGE IN STORM MOTION HAS RESULTED
IN A SIGNIFICANT EASTWARD SHIFT IN THE ANTICIPATED TRACK, WHICH NOW
TAKES THE SYSTEM OVER TUTUILA, AMERICAN SAMOA WITHIN THE NEXT 24
HOURS. THE NEAR-EQUATORIAL RIDGE WILL REMAIN THE PRIMARY STEERING
INFLUENCE THROUGHOUT THE FORECAST PERIOD, ALTHOUGH THE RIDGE IS
EXPECTED TO WEAKEN AND STEER THE SYSTEM MORE SLOWLY POLEWARD IN THE
MEDIUM TO EXTENDED RANGE. TC 20P WILL REMAIN QUITE INTENSE FOR THE
NEXT FEW DAYS DUE TO STRONG POLEWARD OUTFLOW AND PASSAGE OVER VERY
WARM WATER. GRADUAL WEAKENING IS ANTICIPATED LATER IN THE FORECAST
PERIOD DUE TO INCREASING VERTICAL WIND SHEAR AND DECREASING
DIVERGENCE ALOFT. NUMERICAL MODELS ARE GENERALLY IN GOOD AGREEMENT
REGARDING THE OVERALL FORECAST SCENARIO, PARTICULARLY IN THE NEAR-
TERM, ALTHOUGH SPREAD INCREASES SIGNIFICANTLY IN THE LATER TAUS AS A
FEW MODELS DEPICT THE SYSTEM STALLING AS IT DISSIPATES WHILE OTHERS
DEPICT ACCELERATION INTO THE MID-LATITUDE WESTERLY FLOW PATTERN. THE
CURRENT FORECAST LIES CLOSE TO THE MULTI-MODEL CONSENSUS WITH HIGH
CONFIDENCE IN THE NEAR-TERM AND LOW CONFIDENCE IN THE EXTENDED
PERIOD. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 230600Z IS 28 FEET. NEXT
WARNINGS AT 232100Z AND 240900Z.//
=========================================================================
WTPS31 PGTW 20160423 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 015//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 015
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
231200Z --- NEAR 13.4S 172.0W
MOVEMENT PAST SIX HOURS - 115 DEGREES AT 13 KTS
POSITION ACCURATE TO WITHIN 045 NM
POSITION BASED ON CENTER LOCATED BY A COMBINATION OF
SATELLITE AND SYNOPTIC DATA
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
REPEAT POSIT: 13.4S 172.0W
---
FORECASTS:
12 HRS, VALID AT:
240000Z --- 14.2S 170.6W
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 130 DEG/ 04 KTS
---
24 HRS, VALID AT:
241200Z --- 14.7S 170.0W
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 145 DEG/ 02 KTS
---
36 HRS, VALID AT:
250000Z --- 15.0S 169.8W
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 165 DEG/ 02 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
251200Z --- 15.4S 169.7W
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 170 DEG/ 01 KTS
---
72 HRS, VALID AT:
261200Z --- 15.9S 169.6W
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 130 DEG/ 04 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
271200Z --- 16.9S 168.4W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 110 DEG/ 05 KTS
---
120 HRS, VALID AT:
281200Z --- 17.6S 166.5W
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
231500Z POSITION NEAR 13.6S 171.7W.
TROPICAL CYCLONE 20P (AMOS), LOCATED APPROXIMATELY 93 NM NORTHWEST
OF PAGO PAGO, HAS TRACKED EAST-SOUTHEASTWARD AT 13 KNOTS OVER THE
PAST SIX HOURS. THE CURRENT POSITION IS BASED ON RECENT SATELLITE
FIXES FROM PGTW, KNES, AND PHFO. THE INTENSITY OF 90 KNOTS IS
CONSISTENT WITH SUBJECTIVE DVORAK CURRENT INTENSITY ESTIMATES FROM
MULTIPLE REPORTING AGENCIES. TC 20P HAS CONTINUED TO TRACK RAPIDLY
EAST-SOUTHEASTWARD UNDER THE STEERING INFLUENCE OF A NEAR-EQUATORIAL
RIDGE DURING THE PAST SIX HOURS. BASED ON RECENT STORM MOTION, NEAR-
TERM FORECAST TRACK SPEEDS HAVE INCREASED AND THE NEAR- TO MEDIUM-
TERM TRACK FORECAST HAS SHIFTED SLIGHTLY TO THE EAST FROM THE
PREVIOUS FORECAST. THE CENTER OF TC 20P IS NOW EXPECTED TO PASS NEAR
TUTUILA, AMERICAN SAMOA WITHIN THE NEXT 12 TO 18 HOURS. NEAR-
EQUATORIAL RIDGING WILL LIKELY REMAIN THE PRIMARY STEERING INFLUENCE
THROUGHOUT THE FORECAST PERIOD. HOWEVER, TRACK SPEED IS EXPECTED TO
DECREASE SIGNIFICANTLY BETWEEN 12 AND 36 HOURS DUE TO AN
ANTICIPATED, TEMPORARY WEAKENING OF THE STEERING RIDGE. STRONG
POLEWARD OUTFLOW AND PASSAGE OVER WARM WATER HAVE ENABLED TC 20P TO
MAINTAIN INTENSITY DESPITE A SLIGHTLY INCREASE IN VERTICAL WIND
SHEAR OVER THE PAST SIX HOURS. GRADUAL WEAKENING IS ANTICIPATED IN
THE MEDIUM TO EXTENDED FORECAST PERIOD DUE TO INCREASING VERTICAL
WIND SHEAR AND DECREASING DIVERGENCE ALOFT. NUMERICAL MODELS ARE
GENERALLY IN GOOD AGREEMENT REGARDING THE OVERALL FORECAST SCENARIO,
PARTICULARLY IN THE NEAR-TERM, ALTHOUGH SPREAD INCREASES
SIGNIFICANTLY IN THE LATER TAUS AS A FEW MODELS DEPICT THE SYSTEM
STALLING AND DISSIPATING WHILE OTHERS DEPICT ACCELERATION INTO THE
MID-LATITUDE WESTERLY FLOW PATTERN. THE CURRENT FORECAST LIES CLOSE
TO THE MULTI-MODEL CONSENSUS WITH HIGH CONFIDENCE IN THE NEAR-TERM
TRACK DIRECTION AND LOW CONFIDENCE IN TRACK DIRECTION AND SPEED
DURING THE EXTENDED PERIOD. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
231200Z IS 28 FEET. NEXT WARNINGS AT 232100Z, 240300Z, 240900Z AND
241500Z.//
=========================================================================
WTPS31 PGTW 20160423 21:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 016//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 016
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
231800Z --- NEAR 14.0S 170.4W
MOVEMENT PAST SIX HOURS - 115 DEGREES AT 16 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
015 NM SOUTHWEST QUADRANT
015 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
REPEAT POSIT: 14.0S 170.4W
---
FORECASTS:
12 HRS, VALID AT:
240600Z --- 14.8S 168.7W
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 160 DEG/ 04 KTS
---
24 HRS, VALID AT:
241800Z --- 15.5S 168.4W
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 155 DEG/ 02 KTS
---
36 HRS, VALID AT:
250600Z --- 15.9S 168.2W
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 155 DEG/ 02 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
251800Z --- 16.3S 168.0W
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 140 DEG/ 03 KTS
---
72 HRS, VALID AT:
261800Z --- 17.3S 167.1W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 125 DEG/ 04 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
271800Z --- 18.3S 165.7W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 105 DEG/ 05 KTS
---
120 HRS, VALID AT:
281800Z --- 18.9S 163.6W
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
232100Z POSITION NEAR 14.2S 170.0W. TROPICAL CYCLONE 20P (AMOS),
LOCATED APPROXIMATELY 25 NM NORTHEAST OF PAGO PAGO, HAS TRACKED EAST-
SOUTHEASTWARD AT 16 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED
INFRARED IMAGERY CONTINUES TO DEPICT DEEP CONVECTION FORMING A
CENTRAL DENSE OVERCAST OBSCURING THE LOW LEVEL CIRCULATION CENTER. A
231748Z SSMIS 89 GHZ MICROWAVE IMAGE SHOWS A COMPACT SYSTEM WITH THE
DEEP CONVECTION MOSTLY TO THE EASTERN PERIPHERY BUT A SMALL HOOK
FEATURE INDICATING THE CENTER OF THE SYSTEM, LENDING MODERATE
CONFIDENCE TO THE INITIAL POSITION. THE CURRENT INTENSITY IS
ASSESSED AT 90 KNOTS IN CONGRUENCE WITH SUBJECTIVE DVORAK CURRENT
INTENSITY ESTIMATES FROM PGTW/KNES/NFFN. TC AMOS SPED UP OVER THE
PAST SIX HOURS WHILE CONTINUING TO TRACK EAST-SOUTHEASTWARD UNDER
THE STEERING INFLUENCE OF A NEAR-EQUATORIAL RIDGE (NER) LOCATED TO
THE NORTHEAST. BASED ON RECENT SURFACE OBSERVATIONS AND ASSESSMENTS
OF AVAILABLE SATELLITE AND MICROWAVE IMAGERY, THE CENTER OF TC AMOS
IS ASSESSED TO HAVE PASSED VERY NEAR AMERICAN SAMOA AT APPROXIMATELY
231730Z AND CONFIRMS THE INCREASE IN TRACK SPEED. HOWEVER, THE
FORECAST PHILOSOPHY AND OVERALL TRACK REMAIN ESSENTIALLY UNCHANGED.
THE AFOREMENTIONED NER WILL REMAIN THE PRIMARY STEERING INFLUENCE
THROUGHOUT THE FORECAST PERIOD. HOWEVER, TRACK SPEED IS EXPECTED TO
DECREASE RAPIDLY OVER THE NEXT 24 HOURS DUE TO AN ANTICIPATED,
TEMPORARY WEAKENING OF THE STEERING RIDGE. AFTER TAU 72, TRACK SPEED
INCREASES AS THE NER STRENGTHENS AGAIN. TC AMOS HAS MAINTAINED
STRONG POLEWARD OUTFLOW INTO THE BASE OF AN UPPER LEVEL TROUGH OVER
THE PAST TWELVE HOURS, ENABLING THE SYSTEM TO MAINTAIN INTENSITY
DESPITE INCREASING VERTICAL WIND SHEAR (VWS). HOWEVER, THE SYSTEM
HAS PEAKED IN INTENSITY AND A GRADUAL WEAKENING IS ANTICIPATED
THROUGH THE ENTIRE FORECAST PERIOD DUE TO INCREASING VWS AND A
REDUCTION IN OUTFLOW AS THE UPPER LEVEL TROUGH EXITS THE AREA AFTER
TAU 24. NUMERICAL MODELS ARE GENERALLY IN GOOD AGREEMENT REGARDING
THE OVERALL FORECAST SCENARIO WITH INCREASING UNCERTAINTY REGARDING
TRACK SPEED AND INTENSITY BEYOND TAU 36 RESULTING IN LOW CONFIDENCE
IN THE FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 231800Z IS
30 FEET. NEXT WARNINGS AT 240300Z, 240900Z, 241500Z AND 242100Z.//
=========================================================================
WTPS31 PGTW 20160424 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING RELOCATED//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 017 RELOCATED
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
240000Z --- NEAR 13.9S 171.0W
MOVEMENT PAST SIX HOURS - 125 DEGREES AT 07 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT
010 NM SOUTHEAST QUADRANT
010 NM SOUTHWEST QUADRANT
010 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
REPEAT POSIT: 13.9S 171.0W
---
FORECASTS:
12 HRS, VALID AT:
241200Z --- 14.4S 169.8W
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 130 DEG/ 05 KTS
---
24 HRS, VALID AT:
250000Z --- 15.0S 169.1W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 145 DEG/ 02 KTS
---
36 HRS, VALID AT:
251200Z --- 15.4S 168.8W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 170 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
260000Z --- 16.0S 168.7W
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 150 DEG/ 03 KTS
---
72 HRS, VALID AT:
270000Z --- 17.1S 168.1W
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 120 DEG/ 05 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
280000Z --- 18.0S 166.3W
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 120 HR POSIT: 070 DEG/ 07 KTS
---
120 HRS, VALID AT:
290000Z --- 17.0S 163.6W
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
240300Z POSITION NEAR 14.0S 170.7W.
TROPICAL CYCLONE 20P (AMOS), LOCATED APPROXIMATELY 30 NM
NORTHWEST OF PAGO PAGO, HAS TRACKED SOUTHEASTWARD AT 07 KNOTS
OVER THE PAST SIX HOURS. AVAILABILITY OF HIGH RESOLUTION ANIMATED
VISIBLE SATELLITE IMAGERY AND ADJUSTED FIX POSITION DATA HAS
RESULTED IN A RELOCATION OF TC AMOS. LATEST IMAGERY DEPICTS A
SIGNIFICANTLY WEAKENED SYSTEM, WITH THE LOW LEVEL CIRCULATION CENTER
(LLCC) POSSIBLY BECOMING SEPARATED FROM A SIGNIFICANTLY WEAKER
CONVECTIVE SIGNATURE. A 232100Z AMSU-B 89 GHZ MICROWAVE IMAGE SHOWED
A LIKELY LLCC STILL TO THE NORTH OF PAGO PAGO, AMERICAN SAMOA, WITH
DEEP CONVECTION ISOLATED TO THE EASTERN PERIPHERY. SURFACE
OBSERVATIONS FROM PAGO PAGO INDICATE SURFACE WINDS HAVE BEEN FROM
THE EAST OVER THE PAST FOUR HOURS, WHICH PROVIDES FURTHER SUPPORT TO
THE RELOCATED INITIAL POSITION, THOUGH THE OVERALL CONFIDENCE IN THE
POSITION IS LOW. THE CURRENT INTENSITY IS ASSESSED AT 70 KNOTS
BETWEEN SUBJECTIVE DVORAK CURRENT INTENSITY ESTIMATES FROM PGTW AND
KNES (77 AND 65 KNOTS RESPECTIVELY). TC AMOS HAS CONTINUED TO TRACK
TOWARDS THE SOUTHEAST UNDER THE STEERING INFLUENCE OF A NEAR-
EQUATORIAL RIDGE (NER), BUT ACTUALLY SLOWED SINCE 1200Z VICE SPED UP
AS DISCUSSED IN THE PREVIOUS WARNING DISCUSSION. THE AFOREMENTIONED
NER WILL BUILD IN ON THE EASTERN SIDE OF THE SYSTEM, SLOWING AND
SHIFTING THE TRACK TO A MORE SOUTHERLY DIRECTION BY TAU 36. AFTER
TAU 72, THE SYSTEM BECOMES EXTREMELY WEAK AS IT IS SHEARED APART AND
THE PRIMARY STEERING SHIFTS TO THE LOW LEVEL SUBTROPICAL RIDGE (STR)
FAR TO THE SOUTHWEST, RESULTING IN A GENTLE TURN TOWARDS THE
NORTHEAST THROUGH THE REMAINDER OF THE FORECAST PERIOD. TC AMOS IS
STILL TAPPING INTO THE BASE OF A MID-LATITUDE TROUGH, PROVIDING
VIGOROUS POLEWARD OUTFLOW. THIS IS BEING OFFSET HOWEVER, BY MODERATE
VERTICAL WIND SHEAR (VWS) OF 20-25 KNOTS FROM THE WEST. THE
BREAKDOWN OF THE WARM CORE HAS RESULTED IN THE SIGNIFICANT WEAKENING
REFLECTED IN THE CONVECTIVE STRUCTURE. AS TC AMOS CONTINUES TRACKING
SOUTH-SOUTHEASTWARD, VWS WILL CONTINUE TO INCREASE LEADING TO
FURTHER WEAKENING UNTIL DISSIPATING OVER WATER BY TAU 120. NUMERICAL
MODELS ARE GENERALLY IN GOOD AGREEMENT THROUGH TAU 36 AND THE TRACK
FORECAST LIES NEAR THE MULTI-MODEL CONSENSUS AND THE ECMWF TRACK
FORECAST. THERE IS INCREASING UNCERTAINTY REGARDING TRACK AND
INTENSITY BEYOND TAU 36, PROVIDING LOW CONFIDENCE IN THE FORECAST
TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 240000Z IS 26 FEET. NEXT
WARNINGS AT 240900Z, 241500Z, 242100Z AND 250300Z. JUSTIFICATION FOR
RELOCATION: RELOCATED INITIAL POSITION OF TC 20P BASED ON UPDATED
18Z FIX POSITION AND REANALYSIS OF AVAILABLE MICROWAVE AND VISIBLE
SATELLITE IMAGERY.//
=========================================================================
WTPS31 PGTW 20160424 09:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 018//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 018
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
240600Z --- NEAR 13.7S 170.2W
MOVEMENT PAST SIX HOURS - 090 DEGREES AT 07 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
REPEAT POSIT: 13.7S 170.2W
---
FORECASTS:
12 HRS, VALID AT:
241800Z --- 14.0S 169.5W
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 135 DEG/ 03 KTS
---
24 HRS, VALID AT:
250600Z --- 14.4S 169.1W
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 36 HR POSIT: 150 DEG/ 03 KTS
---
36 HRS, VALID AT:
251800Z --- 14.9S 168.8W
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 48 HR POSIT: 155 DEG/ 02 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
260600Z --- 15.3S 168.6W
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
240900Z POSITION NEAR 13.8S 170.0W.
TROPICAL CYCLONE 20P (AMOS), LOCATED APPROXIMATELY 46 NM NORTHEAST
OF PAGO PAGO, HAS TRACKED EASTWARD AT 07 KNOTS OVER THE PAST SIX
HOURS. THE CURRENT POSITION IS BASED ON RECENT SATELLITE FIXES FROM
PGTW, KNES, PHFO, AND ABRF AND A 240624Z SSMIS IMAGE. THERE IS LOW
CONFIDENCE IN THE INITIAL POSITION DUE TO THE INCREASINGLY
INDISTINCT SIGNATURE OF THE LOW LEVEL CIRCULATION CENTER. THE
INTENSITY OF 50 KNOTS IS SET WITHIN A RANGE OF SUBJECTIVE DVORAK
CURRENT INTENSITY ESTIMATES, BETWEEN 45 AND 65 KNOTS, AND IS
CONSISTENT WITH THE PREVIOUSLY-OBSERVED WEAKENING TREND. TC 20P IS
RAPIDLY WEAKENING IN RESPONSE TO PERSISTENT, MODERATE WESTERLY
VERTICAL WIND SHEAR. ANIMATED INFRARED AND MICROWAVE SATELLITE
IMAGERY INDICATE THAT THE REMAINING DEEP CONVECTION IS CONFINED TO
THE EASTERN PERIPHERY OF THE CIRCULATION. THE SYSTEM IS TRACKING
EASTWARD ALONG THE PERIPHERY OF NEAR-EQUATORIAL RIDGING SITUATED TO
THE NORTH AND EAST. THIS RIDGE IS EXPECTED TO REMAIN THE PRIMARY
STEERING INFLUENCE THROUGHOUT THE FORECAST PERIOD, WHICH HAS BEEN
REDUCED TO 48 HOURS DUE TO EXPECTED DISSIPATION OF THE CYCLONE IN
THE PRESENCE OF PERSISTENT VERTICAL WIND SHEAR. NUMERICAL MODELS
GENERALLY DEPICT A SLOW EASTWARD AND POLEWARD TRACK OVER THE NEXT
TWO DAYS, ALTHOUGH THE MODELS HAVE FORECASTED A MORE PRONOUNCED
POLEWARD TRACK THAN OBSERVED OVER MANY OF THE MOST RECENT RUNS.
GIVEN THIS TENDENCY, THE CURRENT FORECAST TRACK IS PLACED A BIT
EQUATORWARD AND TO THE EAST OF THE MULTI-MODEL CONSENSUS WITH LOW
CONFIDENCE. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 240600Z IS 18 FEET.
NEXT WARNINGS AT 241500Z, 242100Z, 250300Z AND 250900Z.//
=========================================================================
WTPS31 PGTW 20160424 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 019//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 019
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
241200Z --- NEAR 13.7S 169.5W
MOVEMENT PAST SIX HOURS - 090 DEGREES AT 07 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
REPEAT POSIT: 13.7S 169.5W
---
FORECASTS:
12 HRS, VALID AT:
250000Z --- 13.8S 168.9W
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 24 HR POSIT: 120 DEG/ 03 KTS
---
24 HRS, VALID AT:
251200Z --- 14.1S 168.4W
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
241500Z POSITION NEAR 13.7S 169.3W.
TROPICAL CYCLONE 20P (AMOS), LOCATED APPROXIMATELY 79 NM EAST-
NORTHEAST OF PAGO PAGO, HAS TRACKED EASTWARD AT 07 KNOTS OVER THE
PAST SIX HOURS. THE CURRENT POSITION IS BASED ON RECENT SATELLITE
FIXES FROM PGTW, KNES, AND PHFO, A 240844Z AMSU IMAGE, AND A 240932Z
AMSU IMAGE. THERE IS LOW CONFIDENCE IN THE INITIAL POSITION DUE TO
THE INCREASINGLY INDISTINCT SIGNATURE OF THE LOW LEVEL CIRCULATION
CENTER. THE INTENSITY OF 40 KNOTS IS BASED ON A CONSENSUS OF
SUBJECTIVE DVORAK FINAL T-NUMBER AND CURRENT INTENSITY ESTIMATES
FROM MULTIPLE REPORTING AGENCIES, AND IS ALSO CONSISTENT WITH THE
PREVIOUSLY-OBSERVED WEAKENING TREND. TC 20P CONTINUES TO RAPIDLY
WEAKEN IN RESPONSE TO PERSISTENT VERTICAL WIND SHEAR AS IT TRACKS
EASTWARD ALONG THE PERIPHERY OF NEAR-EQUATORIAL RIDGING SITUATED TO
THE NORTH AND EAST. THE CYCLONE IS NOW EXPECTED TO DISSIPATE BELOW
THE WARNING THRESHOLD INTENSITY OF 35 KNOTS BY TAU 24 AS PERSISTENT
SHEAR CONTINUES TO IMPACT THE SYSTEM. NUMERICAL MODELS ARE IN GOOD
AGREEMENT WITH THE OVERALL FORECAST SCENARIO. THE CURRENT FORECAST
TRACK LIES NEAR, BUT SLIGHTLY TO THE EAST OF, THE MULTI-MODEL
CONSENSUS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 241200Z IS 14 FEET.
NEXT WARNINGS AT 242100Z, 250300Z AND 250900Z.//
=========================================================================
WTPS31 PGTW 20160424 21:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (AMOS) WARNING NR 020//
RMKS/
1. TROPICAL CYCLONE 20P (AMOS) WARNING NR 020
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
241800Z --- NEAR 14.3S 168.4W
MOVEMENT PAST SIX HOURS - 120 DEGREES AT 12 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
REPEAT POSIT: 14.3S 168.4W
---
FORECASTS:
12 HRS, VALID AT:
250600Z --- 15.5S 166.8W
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
242100Z POSITION NEAR 14.6S 168.0W. TROPICAL CYCLONE 20P (AMOS),
LOCATED APPROXIMATELY 134 NM EAST OF PAGO PAGO, AMERICAN SAMOA, HAS
TRACKED EAST-SOUTHEASTWARD AT 12 KNOTS OVER THE PAST SIX HOURS.
ANIMATED INFRARED AND VISIBLE IMAGERY DEPICT A VERY SHEARED SYSTEM
WITH A BROAD BAND OF CIRRUS CLOUDS OBSCURING ANY VIEW OF THE LOW
LEVEL CIRCULATION CENTER (LLCC). A 241720Z SSMIS 91 GHZ MICROWAVE
IMAGE SHOWED A BROAD, ELONGATED AND INDISTINCT CIRCULATION. THE
INITIAL POSITION IS PLACED BETWEEN THE PGTW AND KNES FIX POSITIONS
WITH LOW CONFIDENCE. THE INITIAL INTENSITY IS ASSESSED AT 35 KNOTS
BASED ON A CONSENSUS OF SUBJECTIVE DVORAK FINAL T-NUMBER AND CURRENT
INTENSITY ESTIMATES FROM MULTIPLE REPORTING AGENCIES, AND IS ALSO
CONSISTENT WITH THE PREVIOUSLY-OBSERVED WEAKENING TREND. TC 20P
CONTINUES TO RAPIDLY WEAKEN IN RESPONSE TO PERSISTENT WESTERLY
VERTICAL WIND SHEAR (VWS) AS IT TRACKS GENERALLY EAST-SOUTHEASTWARD
ALONG THE PERIPHERY OF A NEAR-EQUATORIAL RIDGE. DISSIPATION OF THE
CYCLONE IS IMMINENT AS PERSISTENT SHEAR CONTINUES TO IMPACT THE
SYSTEM, PREVENTING REINTENSIFICATION. THIS IS THE FINAL WARNING ON
THIS SYSTEM BY THE JOINT TYPHOON WRNCEN PEARL HARBOR HI. THE SYSTEM
WILL BE CLOSELY MONITORED FOR SIGNS OF REGENERATION. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 241800Z IS 18 FEET.//
Tropical cyclone tracks developed by Michael Bath using operational warnings and advisories.
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Document: tropical_cyclone_amos_jtwc_advisories.htm
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