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Tropical Cyclone 201318
Southern Hemisphere Summary
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Cyclones
[Index] |
Tropical Cyclone 201318 Southern Hemisphere Summary |
WTXS22 PGTW 20130224 02:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
A 160 NM RADIUS OF 11.2S 98.3E 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 25 TO 30 KNOTS. METSAT IMAGERY AND SYNOPTIC DATA AT 240130Z
INDICATE THAT A CIRCULATION CENTER IS LOCATED NEAR 11.2S 98.3E. THE
SYSTEM IS MOVING NORTHWARD AT 06 KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 12.3S
98.0E, IS NOW LOCATED NEAR 11.2S 98.3E, APPROXIMATELY 100 NM EAST-
NORTHEAST OF COCOS ISLAND, AUSTRALIA. ANIMATED INFRARED SATELLITE
IMAGERY INDICATES A CONSOLIDATING LOW-LEVEL CIRCULATION CENTER
(LLCC) WITH IMPROVED DEEP CONVECTIVE BANDING OVER THE WESTERN SEMI-
CIRCLE. A 232222Z SSMIS IMAGE SHOWS AN ELONGATED LLCC WITH
FRAGMENTED DEEP CONVECTIVE BANDING WRAPPING FROM THE SOUTH QUADRANT
INTO THE NORTH QUADRANT AND TIGHTLY-CURVED SHALLOW CONVECTIVE
BANDING ELSEWHERE. SURFACE OBSERVATIONS FROM COCOS ISLAND INDICATE
SUSTAINED SURFACE WINDS AT 15 TO 20 KNOTS WITH SLP NEAR 1001 MB AND
24-HOUR SLP DECREASE OF 3 MB. UPPER-LEVEL ANALYSIS INDICATES THAT
THE LLCC IS LOCATED JUST EQUATORWARD OF THE SUBTROPICAL RIDGE AXIS
AND IS UNDER MODERATE TO HIGH (20 TO 30 KNOTS) VERTICAL WIND SHEAR
WITH GOOD POLEWARD OUTFLOW. DYNAMIC MODELS INDICATE SLOW DEVELOPMENT
OVER THE NEXT ONE TO TWO DAYS. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1000 MB. 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
250200Z.//
=========================================================================
WTXS33 PGTW 20130224 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 001//
REF/A/JOINT TYPHOON WRNCEN PEARL HARBOR HI/240153Z FEB 13//
AMPN/ REF A IS A TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 001
03 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
241200Z --- NEAR 12.6S 97.4E
MOVEMENT PAST SIX HOURS - 270 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
REPEAT POSIT: 12.6S 97.4E
---
FORECASTS:
12 HRS, VALID AT:
250000Z --- 13.1S 97.1E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 180 DEG/ 03 KTS
---
24 HRS, VALID AT:
251200Z --- 13.7S 97.1E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 165 DEG/ 02 KTS
---
36 HRS, VALID AT:
260000Z --- 14.1S 97.2E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 120 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
261200Z --- 14.4S 97.7E
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 - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 105 DEG/ 02 KTS
---
72 HRS, VALID AT:
271200Z --- 14.6S 98.6E
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 - 085 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 100 DEG/ 06 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
281200Z --- 15.0S 101.1E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 110 DEG/ 10 KTS
---
120 HRS, VALID AT:
011200Z --- 16.2S 105.1E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
241500Z POSITION NEAR 12.7S 97.3E.
TROPICAL CYCLONE (TC) 18S, LOCATED APPROXIMATELY 45 NM SOUTHEAST OF
COCOS ISLAND, AUSTRALIA, HAS TRACKED WESTWARD AT 12 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
(MSI) DEPICTS A FULLY EXPOSED AND WELL DEFINED LOW-LEVEL CIRCULATION
CENTER (LLCC) WITH DEEP CONVECTION SHEARED 30NM WEST OF THE LLCC. A
241059Z SSMIS MICROWAVE IMAGE SHOWS THE LLCC HAS BECOME MORE TIGHTLY
WRAPPED OVER THE PAST 12 HOURS DESPITE THE HIGH VERTICAL WIND SHEAR
(VWS) ON THE SYSTEM. THERE IS HIGH CONFIDENCE IN THE INITIAL
POSITION BASED ON THE WELL-DEFINED LLCC IN THE MSI. THE INITIAL
INTENSITY IS ASSESSED AT 35 KNOTS, WHICH IS SLIGHTLY HIGHER THAN
DVORAK INTENSITY ESTIMATES FROM PGTW AND KNES DUE TO SURFACE
OBSERVATIONS AT COCOS ISLAND, 45 NM NORTHWEST OF THE SYSTEM, AND THE
IMPROVING STRUCTURE. AN OLDER 240500Z OSCAT PASS ADDITIONALLY SHOWED
SOME 35 KNOT WINDS NEAR THE LLCC. UPPER-LEVEL ANALYSIS REVEALS TC
18S IS IN A MARGINAL ENVIRONMENT AS FAVORABLE DIFFLUENCE ALOFT IS
BEING OFFSET BY HIGH (20 TO 30 KNOT) VWS. TC 18S CURRENTLY TRACKING
ERRATICALLY AS THERE ARE COMPETING STEERING INFLUENCES FROM THE NEAR
EQUATORIAL RIDGE TO THE NORTH AND THE SUBTROPICAL STEERING RIDGE TO
THE SOUTH. TC 18S IS FORECAST TO SLOWLY DRIFT SOUTH IN THIS WEAK
STEERING ENVIRONMENT FOR THE NEXT TWO DAYS UNTIL THE NEAR EQUATORIAL
RIDGE TO THE NORTH AMPLIFIES AND DRIVES THE SYSTEM EAST THROUGH THE
REST OF THE FORECAST PERIOD. TC 18S IS FORECAST TO INTENSIFY THROUGH
THE FORECAST PERIOD AS VWS IS FORECAST TO WEAKEN AND OUTFLOW
IMPROVES. DYNAMIC MODEL GUIDANCE IS SPREAD THROUGH THE NEXT 48 HOURS
DUE TO THE WEAK STEERING ENVIRONMENT, BUT GENERALLY AGREES ON THE
EASTWARD TRACK AFTER TAU 48. DUE TO THIS SPREAD AND THE CURRENT WEAK
STEERING ENVIRONMENT THERE IS LOW CONFIDENCE IN THE FORECAST TRACK
WHICH IS POSITIONED CLOSE TO MULTI-MODEL CONSENSUS. THIS WARNING
SUPERSEDES AND CANCELS REF A, JOINT TYPHOON WRNCEN PEARL HARBOR HI
240153Z FEB 13 TROPICAL CYCLONE FORMATION ALERT (WTXS22 PGTW
240200). MAXIMUM SIGNIFICANT WAVE HEIGHT AT 241200Z IS 10 FEET. NEXT
WARNINGS AT 250300Z AND 251500Z. REFER TO TROPICAL CYCLONE 16S
(HARUNA) WARNINGS (WTXS31 PGTW) AND TROPICAL CYCLONE 17S (RUSTY)
WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.//
=========================================================================
WTXS33 PGTW 20130225 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 002//
RMKS/
1. TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 002
03 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
250000Z --- NEAR 13.5S 98.3E
MOVEMENT PAST SIX HOURS - 150 DEGREES AT 06 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 - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
REPEAT POSIT: 13.5S 98.3E
---
FORECASTS:
12 HRS, VALID AT:
251200Z --- 13.9S 98.5E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 150 DEG/ 03 KTS
---
24 HRS, VALID AT:
260000Z --- 14.4S 98.8E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 130 DEG/ 02 KTS
---
36 HRS, VALID AT:
261200Z --- 14.7S 99.2E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 110 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
270000Z --- 14.9S 99.8E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 090 DEG/ 05 KTS
---
72 HRS, VALID AT:
280000Z --- 14.9S 102.0E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 095 DEG/ 08 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
010000Z --- 15.1S 105.1E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 095 DEG/ 10 KTS
---
120 HRS, VALID AT:
020000Z --- 15.6S 109.4E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
250300Z POSITION NEAR 13.6S 98.3E.
TROPICAL CYCLONE (TC) 18S, LOCATED APPROXIMATELY 120 NM SOUTHEAST OF
COCOS ISLAND, AUSTRALIA, HAS TRACKED SOUTH-SOUTHEASTWARD AT 06 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
DEPICTS AN EXPOSED BUT WELL-DEFINED LOW-LEVEL CIRCULATION CENTER
WITH DEEP CONVECTION SHEARED ABOUT 45 NM WEST OF THE CENTER DUE TO
STRONG EASTERLY VERTICAL WIND SHEAR (VWS). TC 18S HAS CONTINUED TO
STRUGGLE DUE TO THE POOR UPPER-LEVEL ENVIRONMENT, HOWEVER, A 242014Z
AMSU IMAGE INDICATES BETTER ORGANIZED SHALLOW BANDING WRAPPING INTO
A WELL-DEFINED LLCC. A 241434Z ASCAT IMAGE SHOWED 40 TO 45 KNOT
WINDS OVER THE NORTH QUADRANT AND SURFACE OBSERVATIONS FROM COCOS
ISLAND HAVE REMAINED STEADY AT 30 TO 35 KNOTS SUSTAINED WITH GUSTS
TO 40 TO 50 KNOTS. THE INITIAL INTENSITY IS ASSESSED AT 40 KNOTS,
SLIGHTLY HIGHER THAN DVORAK INTENSITY ESTIMATES OF 35 KNOTS, BASED
ON THE ASCAT IMAGE. THERE IS GOOD CONFIDENCE IN THE INITIAL POSITION
BASED ON THE EXPOSED CENTER IN VISIBLE IMAGERY. TC 18S IS FORECAST
TO TRACK EASTWARD UNDER THE STEERING INFLUENCE OF THE NEAR-
EQUATORIAL RIDGE THROUGH THE FORECAST PERIOD. DYNAMIC MODEL GUIDANCE
IS IN FAIR AGREEMENT, THEREFORE, THE JTWC FORECAST IS POSITIONED
CLOSE TO THE MULTI-MODEL CONSENSUS. TC 18S IS EXPECTED TO SLOWLY
INTENSIFY THROUGH TAU 120 DUE TO PERSISTENT MODERATE TO STRONG VWS.
DUE TO THE MARGINAL ENVIRONMENT, THERE IS UNCERTAINTY IN THE
EXTENDED INTENSITY FORECAST, WHICH MAY BE SIGNIFICANTLY LOWER THAN
THE 60 KNOTS CURRENTLY FORECAST TO OCCUR NEAR TAU 120. THERE IS LOW
CONFIDENCE IN THE JTWC FORECAST TRACK DUE TO THE SHEARED NATURE OF
THE SYSTEM AND LARGE DIFFERENCES IN MODEL TRACK SPEED THROUGHOUT THE
FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 250000Z IS 11 FEET.
NEXT WARNINGS AT 251500Z AND 260300Z. REFER TO TROPICAL CYCLONE 16S
(HARUNA) FINAL WARNING (WTXS31 PGTW). REFER TO TROPICAL CYCLONE 17S
(RUSTY) WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.//
=========================================================================
WTXS33 PGTW 20130225 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 003//
RMKS/
1. TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 003
03 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
251200Z --- NEAR 14.6S 98.9E
MOVEMENT PAST SIX HOURS - 140 DEGREES AT 06 KTS
POSITION ACCURATE TO WITHIN 050 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: 14.6S 98.9E
---
FORECASTS:
12 HRS, VALID AT:
260000Z --- 14.9S 99.2E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 035 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 125 DEG/ 02 KTS
---
24 HRS, VALID AT:
261200Z --- 15.1S 99.5E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 035 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 100 DEG/ 02 KTS
---
36 HRS, VALID AT:
270000Z --- 15.2S 100.0E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 035 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 090 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
271200Z --- 15.2S 100.6E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 095 DEG/ 03 KTS
---
72 HRS, VALID AT:
281200Z --- 15.3S 101.7E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 095 DEG/ 09 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
011200Z --- 15.6S 105.5E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 105 DEG/ 10 KTS
---
120 HRS, VALID AT:
021200Z --- 16.6S 109.7E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
251500Z POSITION NEAR 14.7S 99.0E.
TROPICAL CYCLONE (TC) 18S, LOCATED APPROXIMATELY 980 NM
WEST-NORTHWEST OF LEARMONTH, AUSTRALIA, HAS TRACKED SOUTHEASTWARD AT
06 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY
SHOWS THE MAIN CONVECTION CONTINUES TO BE SHEARED WESTWARD, FULLY
EXPOSING A LOW LEVEL CIRCULATION CENTER THAT APPEARS TO HAVE SLIGHTLY
UNRAVELED. THE INITIAL POSITION IS BASED ON THE ABOVE ANIMATION AND
THE INITIAL INTENSITY IS BASED ON THE HIGH END OF DVORAK ESTIMATES
FROM PGTW, KNES, AND APRF. UPPER LEVEL ANALYSIS INDICATES THE SYSTEM
IS WELL TO THE NORTH OF THE RIDGE AXIS IN AN AREA OF MODERATE TO
STRONG (20-30 KNOT) EASTERLY VERTICAL WIND SHEAR (VWS). THE CYCLONE
IS TRACKING ALONG THE SOUTHERN PERIPHERY OF THE NEAR-EQUATORIAL RIDGE
TO THE NORTH AND IS EXPECTED TO REMAIN ON THIS TRACK THROUGHOUT THE
FORECAST PERIOD. TC 18S WILL CONTINUE TO STRUGGLE OVER THE NEXT TWO
DAYS AS STRONG VWS WILL PERSIST. AFTER TAU 48, THE SYSTEM WILL BEGIN
TO INTENSIFY AS THE VWS DECREASES AS THE RIDGE TO THE SOUTH IS
WEAKENED BY THE APPROACH OF A MID-LATITUDE TROUGH. THE AVAILABLE
NUMERICAL GUIDANCE IS IN OVERALL AGREEMENT WITH AN EASTWARD
PROGRESSION OF THE CYCLONE; HOWEVER, THERE ARE SIGNIFICANT
DIFFERENCES AMONG THE MEMBERS IN TRACK SPEED WITH GFDN THE FASTEST
AND WBAR THE SLOWEST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 251200Z IS
12 FEET. NEXT WARNINGS AT 260300Z AND 261500Z. REFER TO TROPICAL
CYCLONE 17S (RUSTY) WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES.
=========================================================================
WTXS33 PGTW 20130226 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 004//
RMKS/
1. TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 004
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
260000Z --- NEAR 14.9S 97.9E
MOVEMENT PAST SIX HOURS - 250 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: 14.9S 97.9E
---
FORECASTS:
12 HRS, VALID AT:
261200Z --- 15.3S 98.0E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 100 DEG/ 02 KTS
---
24 HRS, VALID AT:
270000Z --- 15.4S 98.5E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 36 HR POSIT: 090 DEG/ 02 KTS
---
36 HRS, VALID AT:
271200Z --- 15.4S 99.0E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 48 HR POSIT: 090 DEG/ 03 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
280000Z --- 15.4S 99.6E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 095 DEG/ 03 KTS
---
72 HRS, VALID AT:
010000Z --- 15.5S 100.9E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 100 DEG/ 05 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
020000Z --- 15.8S 102.8E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 105 DEG/ 06 KTS
---
120 HRS, VALID AT:
030000Z --- 16.3S 105.2E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
260300Z POSITION NEAR 15.0S 97.9E.
TROPICAL CYCLONE (TC) 18S, LOCATED APPROXIMATELY 180 NM SOUTH-
SOUTHEAST OF COCOS ISLAND, AUSTRALIA, HAS TRACKED WEST-SOUTHWESTWARD
AT 06 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY (MSI) DEPICTS A BROAD LOW-LEVEL CIRCULATION CENTER
(LLCC) WITH DEEP CONVECTION SHEARED WEST OF THE CENTER. A 260106Z
SSMIS IMAGE DEPICTS WEAK, SHALLOW CONVECTIVE BANDING WRAPPING
LOOSELY INTO A DEFINED LLCC. TC 18S HAS TRACKED ERRATICALLY OVER THE
PAST 12 HOURS. HOWEVER, RECENT MSI INDICATES THAT THE SYSTEM
IS NOW TRACKING SLOWLY EASTWARD. DUE TO THE BROAD NATURE OF THE LLCC
AND LACK OF VISIBLE IMAGERY, THERE HAS BEEN LOW CONFIDENCE IN THE
INITIAL POSITION OVER THE PAST 12 HOURS; HOWEVER, THERE IS INCREASED
CONFIDENCE IN THE CURRENT POSITION BASED ON THE MSI, WHICH SHOWED
THE CENTER WAS LOCATED ABOUT 80 NM WEST OF THE 25/12Z TAU 12
FORECASTED POSITION. TC 18S IS LOCATED WITHIN A COMPETING STEERING
ENVIRONMENT BETWEEN A STRONG HIGH TO THE SOUTH AND A NEAR-EQUATORIAL
RIDGE (NER) TO THE NORTH. TC 18S IS FORECAST TO TRACK SLOWLY
EASTWARD THROUGH TAU 48 DUE TO THE COMPLEX STEERING ENVIRONMENT AND
IS EXPECTED TO ACCELERATE EASTWARD AFTER TAU 48 AS THE SUBTROPICAL
HIGH TO THE SOUTH WEAKENS AND THE NER BECOMES THE DOMINANT STEERING
INFLUENCE. DYNAMIC MODEL GUIDANCE HAS TRENDED TOWARD A MUCH SLOWER
OVERALL TRACK WITH GFS AND GFDN INDICATING EXCESSIVELY FAST TRACKS,
THEREFORE, THIS FORECAST IS POSITIONED SLOWER THAN THE MULTI-MODEL
CONSENSUS FAVORING THE ECMWF TRACKER. THERE IS LOW CONFIDENCE IN THE
JTWC FORECAST TRACK. TC 18S IS FORECAST TO MAINTAIN AT 35 KNOTS
THROUGH TAU 48 THEN WILL GRADUALLY INTENSIFY TO A PEAK INTENSITY OF
55 KNOTS BY TAU 120 AS VERTICAL WIND SHEAR DECREASES. THERE IS LOW
CONFIDENCE IN THE INTENSITY FORECAST. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 260000Z IS 15 FEET. NEXT WARNINGS AT 261500Z AND 270300Z.
REFER TO TROPICAL CYCLONE 17S (RUSTY) WARNINGS (WTXS32 PGTW) FOR
TWELVE-HOURLY UPDATES.//
=========================================================================
WTXS33 PGTW 20130226 15:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 005//
RMKS/
1. TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 005
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
261200Z --- NEAR 15.5S 98.0E
MOVEMENT PAST SIX HOURS - 165 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 025 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: 15.5S 98.0E
---
FORECASTS:
12 HRS, VALID AT:
270000Z --- 15.6S 98.1E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 090 DEG/ 01 KTS
---
24 HRS, VALID AT:
271200Z --- 15.6S 98.4E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 36 HR POSIT: 090 DEG/ 02 KTS
---
36 HRS, VALID AT:
280000Z --- 15.6S 98.9E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 48 HR POSIT: 100 DEG/ 02 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
281200Z --- 15.7S 99.4E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 105 DEG/ 03 KTS
---
72 HRS, VALID AT:
011200Z --- 16.0S 100.6E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 100 DEG/ 05 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
021200Z --- 16.3S 102.8E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 095 DEG/ 06 KTS
---
120 HRS, VALID AT:
031200Z --- 16.5S 105.1E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
261500Z POSITION NEAR 15.5S 98.0E.
TROPICAL CYCLONE (TC) 18S, LOCATED APPROXIMATELY 1000 NM
WEST-NORTHWEST OF LEARMONTH, AUSTRALIA, HAS TRACKED
SOUTH-SOUTHEASTWARD AT 04 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY SHOWS THE MAIN CONVECTION REMAINS
DETACHED FROM A FULLY EXPOSED LOW LEVEL CIRCULATION THAT HAS BECOME
MORE ELONGATED AND IRREGULAR, MAKING IT DIFFICULT TO PINPOINT THE
CENTER. THE INITIAL POSITION IS BASED ON THE ABOVE ANIMATION WITH
POOR CONFIDENCE. THE INITIAL INTENSITY, ASSESSED HIGHER THAN
MULTI-AGENCY SUBJECTIVE DVORAK ESTIMATES, IS EXTRAPOLATED FROM RECENT
SCATTEROMETER DATA. UPPER LEVEL ANALYSIS INDICATES THE SYSTEM IS IN
AN AREA OF STRONG (30-40 KNOT) EASTERLY VERTICAL WIND SHEAR (VWS).
THE CYCLONE IS CURRENTLY IN A WEAK STEERING ENVIRONMENT BETWEEN THE
NEAR-EQUATORIAL RIDGE (NER) TO THE NORTH AND A SUBTROPICAL RIDGE
(STR) TO THE SOUTH RESULTING IN A VERY SLOW EASTWARD DRIFT. IT IS
EXPECTED TO REMAIN IN THIS STATE OVER THE NEXT 48 HOURS UNTIL THE STR
RECEDES TO THE EAST. AT THAT STAGE, THE NER WILL REBUILD AND RESUME
STEERING AND TRACK THE CYCLONE FASTER EASTWARD. TC 18S IS EXPECTED TO
STRUGGLE AT MODERATE GALE INTENSITY OVER THE NEXT 48 HOURS WITH A
DISTINCT POSSIBILITY OF DISSIPATION. AFTER TAU 48, SHOULD THE CYCLONE
SURVIVE, DECREASING VWS WILL CONTRIBUTE TO A GRADUAL INTENSIFICATION.
THE AVAILABLE NUMERICAL GUIDANCE ARE IN OVERALL AGREEMENT IN
EVENTUALLY TRACKING THE VORTEX EASTWARD BUT WITH SIGNIFICANT
DIFFERENCES IN TRACK SPEED. GIVEN THE UNCERTAINTY IN THE STEERING
MECHANISM, THERE IS LOW CONFIDENCE IN THE JTWC TRACK AND INTENSITY
FORECASTS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 261200Z IS 17 FEET.
NEXT WARNINGS AT 270300Z AND 271500Z. REFER TO TROPICAL CYCLONE 17S
(RUSTY) WARNINGS (WTXS32 PGTW) FOR TWELVE-HOURLY UPDATES. //
=========================================================================
WTXS33 PGTW 20130227 03:00z
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 006//
RMKS/
1. TROPICAL CYCLONE 18S (EIGHTEEN) WARNING NR 006
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
270000Z --- NEAR 15.3S 98.6E
MOVEMENT PAST SIX HOURS - 075 DEGREES AT 04 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
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
REPEAT POSIT: 15.3S 98.6E
---
FORECASTS:
12 HRS, VALID AT:
271200Z --- 15.2S 99.4E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
270300Z POSITION NEAR 15.3S 98.8E.
TROPICAL CYCLONE (TC) 18S, LOCATED APPROXIMATELY 215 NM SOUTH-
SOUTHEAST OF COCOS ISLAND, HAS TRACKED EAST-NORTHEASTWARD AT 04
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS A LOW LEVEL CIRCULATION WITH THE MAJORITY OF DEEP
CONVECTION SHEARED 130 NM TO THE WEST. THE LOW LEVEL CIRCULATION
CENTER (LLCC) REMAINS WELL DEFINED, BUT HAS WEAKENED OVER THE PAST
12 HOURS. RECENT SCATTEROMETRY DATA INDICATES THE WINDS AROUND THE
NORTHERN AND SOUTHWESTERN PERIPHERY ARE AT BEST 30 KNOTS, WITH A
SLIGHT RELAXATION OF THE STRONGEST WINDS OVER THE PAST 18 HOURS.
DVORAK ESTIMATES HAVE INDICATED A WEAKENING TREND FOR THE PAST 12
HOURS, SUPPORTING OBSERVATIONS IN THE SCATTEROMETRY DATA. THE LLCC
IS CURRENTLY TRACKING EASTWARD OVER A COLD POOL OF UNFAVORABLE OCEAN
WATERS (24 TO 26 DEGREES CELSIUS), LEADING TO FURTHER WEAKENING OF
THE LLCC. UPPER LEVEL ANALYSIS INDICATES STRONG EASTERLY FLOW ALOFT
IS CREATING MODERATE TO HIGH (20 TO 30 KNOTS) VERTICAL WIND SHEAR
(VWS) OVER THE LLCC, PREVENTING THE OBSERVED DEEP CONVECTION FROM
BUILDING TOWARDS THE CENTER OF THE SYSTEM. MODEL GUIDANCE HAS
SHIFTED OVER THE PAST 12 HOURS AND NOW INDICATES THE LLCC WILL
DISSIPATE COMPLETELY OVER THE NEXT 24 TO 48 HOURS. THERE REMAINS A
SLIGHT CHANCE THE LLCC WILL MAKE IT INTO A MORE FAVORABLE
ENVIRONMENT IN THE NEXT 48 TO 72 HOURS, LEADING TO A REDEVELOPMENT
OF THE SYSTEM. BASED ON THE INCREASING VWS AND WEAKENING LLCC, 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 270000Z IS 14 FEET.
REFER TO TROPICAL CYCLONE 17S (RUSTY) WARNINGS (WTXS32 PGTW) FOR
TWELVE-HOURLY UPDATES.//
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| Document: tropical_cyclone_201318.htm | Updated: 1 March 2013 |