[Index]
Tropical Cyclone ATU
[Southern Hemisphere Summary][Summaries and Track Data]
| Tropical
Cyclones
[Index] |
Tropical Cyclone ATU [Southern Hemisphere Summary][Summaries and Track Data] |
WTPS21 PGTW 20110218 05:30z
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
160 NM EITHER SIDE OF A LINE FROM 14.0S 169.1E TO 17.9S 171.2E
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 AT 180500Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 14.7S 169.4E. THE SYSTEM IS MOVING SOUTHWESTWARD AT 05
KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 14.1S
169.0E, IS NOW LOCATED NEAR 14.7S 169.4E, APPROXIMATELY 195 NM NORTH-
NORTHEAST OF PORT VILA, VANUATU. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS IMPROVED CONSOLIDATION WITH A DEFINED LOW-LEVEL
CIRCULATION CENTER (LLCC) AND CONVECTIVE BANDING WEST WRAPPING INTO
THE NORTH QUADRANT. A 180249Z AMSU IMAGE DEPICTS DEEP, CURVED
CONVECTIVE BANDING ALONG THE NORTHWEST QUADRANT WITH WEAKER BANDING
NORTH AND NORTHEAST OF THE CENTER. A 172144Z ASCAT IMAGE SHOWS AN
ELONGATED BUT DEFINED CIRCULATION WITH 25-30 KNOT WINDS; OVERALL,
THE CIRCULATION HAS SLOWLY STRENGTHENED OVER THE PAST 24 HOURS. THE
LLCC IS LOCATED UNDER AN UPPER-LEVEL ANTICYCLONE WITH GOOD
EQUATORWARD AND POLEWARD OUTFLOW. POLEWARD OUTFLOW HAS IMPROVED AND
IS BEING ENHANCED BY AN UPPER-LEVEL LOW NEAR 23S 153E (EAST COAST OF
AUSTRALIA) AND UPPER-LEVEL WESTERLIES SOUTH OF THE SYSTEM. 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
FAVORABLE ENVIRONMENT AND EXCELLENT OUTFLOW, THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS GOOD.
=========================================================================
WTPS31 PGTW 20110218 21:00z
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (SEVENTEEN) WARNING NR 001//
REF/A/MSG/NAVMARFCSTCEN PEARL HARBOR HI/180521ZFEB2011//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.//
RMKS/
1. TROPICAL CYCLONE 17P (SEVENTEEN) 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:
181800Z --- NEAR 15.4S 169.4E
MOVEMENT PAST SIX HOURS - 205 DEGREES AT 02 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: 15.4S 169.4E
---
FORECASTS:
12 HRS, VALID AT:
190600Z --- 15.8S 169.2E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 190 DEG/ 03 KTS
---
24 HRS, VALID AT:
191800Z --- 16.4S 169.1E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
000 NM SOUTHWEST QUADRANT
000 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 170 DEG/ 04 KTS
---
36 HRS, VALID AT:
200600Z --- 17.1S 169.2E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 150 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
201800Z --- 18.1S 169.8E
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 - 045 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 145 DEG/ 08 KTS
---
72 HRS, VALID AT:
211800Z --- 20.6S 171.6E
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 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 - 115 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 140 DEG/ 14 KTS
---
LONG RANGE OUTLOOK:
NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 250 NM
ON DAY 4 AND 350 NM ON DAY 5... AND FOR INTENSITY
NEAR 20 KT EACH DAY.
---
96 HRS, VALID AT:
221800Z --- 24.8S 175.5E
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 140 DEG/ 22 KTS
---
120 HRS, VALID AT:
231800Z --- 31.3S 177.6W
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
---
REMARKS:
182100Z POSITION NEAR 15.5S 169.4E.
TROPICAL CYCLONE (TC) 17S, LOCATED APPROXIMATELY 485 NM WEST-
NORTHWEST OF NADI, FIJI, HAS TRACKED SOUTH-SOUTHWESTWARD AT 02 KNOTS
OVER THE PAST SIX HOURS. ANIMATED INFRARED IMAGERY SHOWS THAT DEEP
CONVECTION HAS FORMED OVER THE CENTER OF THE LOW LEVEL CIRCULATION
CENTER (LLCC) AND FORMATIVE BANDING IS NOW WRAPPING INTO THE CENTER
FROM THE WEST AND NORTH SIDES. AN 181753Z TRMM PASS SHOWS DEEP
CURVED CONVECTION SLIGHTLY DISPLACED TO THE NORTHWEST OF THE WELL
DEFINED, SYMMETRIC LOW LEVEL CIRCULATION. ENVIRONMENTAL ANALYSIS
INDICATES THAT THE SYSTEM IS BENEATH AN UPPER LEVEL OUTFLOW SOURCE,
IN A REGION OF LOW (15KTS) VERTICAL WIND SHEAR AND FAVORABLE SEA
SURFACE TEMPERATURES. THE SYSTEM IS CURRENTLY IN A WEAK STEERING
ENVIRONMENT BETWEEN TWO LOW TO MID-LEVEL SUBTROPICAL RIDGES (STR)
(ONE TO THE NORTHEAST AND ONE TO THE SOUTHWEST). AN APPROACHING HIGH
AMPLITUDE MIDLATITUDE TROUGH WILL START TO ERODE THE STR TO THE
SOUTHWEST, ALLOWING THE SECOND STR TO THE NORTHEAST TO TAKE OVER AS
THE PRIMARY STEERING MECHANISM. AROUND TAU 48, THE SYSTEM WILL BEGIN
TO ACCELERATE TO THE SOUTHEAST AHEAD OF THE PASSING TROUGH. WHILE
AHEAD OF THE PASSING TROUGH, POLEWARD OUTFLOW IS EXPECTED TO IMPROVE
SUBSTANTIALLY, AND THE SYSTEM IS EXPECTED TO STEADILY INTENSIFY
THROUGH THIS PERIOD UNTIL IS CROSSES INTO COOLER WATERS BY TAU 108.
BY TAU 120 THE SYSTEM IS EXPECTED TO BEGIN EXTRATROPICAL TRANSITION
UNDER THE INFLUENCES OF INCREASING VERTICAL WIND SHEAR, ENTRAINMENT
OF DRIER AIR FROM A MID-LATITUDE AIRMASS TO THE SOUTH, AND PASSAGE
OVER COOLER WATER. NOGAPS, GFS AND GFDN ARE ALL IN EXCELLENT
AGREEMENT, AND THE FORECAST IS BASED THESE MODELS. THIS WARNING
SUPERSEDES AND CANCELS REF A, NAVMARFCSTCEN 180521Z FEB 11 TROPICAL
CYCLONE FORMATION ALERT (WTPS22 PGTW 180530) MAXIMUM SIGNIFICANT
WAVE HEIGHT AT 181800Z IS 12 FEET. NEXT WARNINGS AT 190900Z AND
192100Z.
=========================================================================
WTPS31 PGTW 20110219 09:00z
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 002//
RMKS/
1. TROPICAL CYCLONE 17P (ATU) 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:
190600Z --- NEAR 16.2S 169.0E
MOVEMENT PAST SIX HOURS - 225 DEGREES AT 04 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 050 KT WINDS - 030 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
REPEAT POSIT: 16.2S 169.0E
---
FORECASTS:
12 HRS, VALID AT:
191800Z --- 16.9S 168.8E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 190 DEG/ 03 KTS
---
24 HRS, VALID AT:
200600Z --- 17.5S 168.7E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 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
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 170 DEG/ 06 KTS
---
36 HRS, VALID AT:
201800Z --- 18.6S 168.9E
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 - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 150 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
210600Z --- 19.6S 169.5E
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 - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 145 DEG/ 08 KTS
---
72 HRS, VALID AT:
220600Z --- 22.1S 171.4E
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 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 - 055 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 140 DEG/ 16 KTS
---
LONG RANGE OUTLOOK:
NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 250 NM
ON DAY 4 AND 350 NM ON DAY 5... AND FOR INTENSITY
NEAR 20 KT EACH DAY.
---
96 HRS, VALID AT:
230600Z --- 27.2S 175.9E
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
VECTOR TO 120 HR POSIT: 135 DEG/ 26 KTS
---
120 HRS, VALID AT:
240600Z --- 34.5S 175.5W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
190900Z POSITION NEAR 16.4S 169.0E.
TROPICAL CYCLONE (TC) 17S (ATU), LOCATED APPROXIMATELY 100 NM WEST-
NORTHWEST OF PORT VILLA HAS TRACKED SOUTHWESTWARD AT 04 KNOTS
OVER THE PAST SIX HOURS. ATU HAS INTENSIFIED 15 KNOTS SINCE
YESTERDAY AND IS BEGINNING TO SHOW SIGNS OF A DEVELOPING EYE IN
MULTISPECTRAL SATELLITE IMAGERY (MSI). THE INTENSITY FORECAST HAS
BEEN ADJUSTED UPWARD TO ACCOUNT FOR THIS DEVELOPMENT. THE CURRENT
FORECAST INTENSITY IS BASED ON DVORAK FIXES FROM PGTW, PHFO, AND
NFFN, WHICH ALL ASSIGN A 3.0 T-NUMBER. THE POSITION IS BASED ON
CONSERVATIVE CLOUD FEATURES IN MSI WITH FAIR CONFIDENCE. THE
STEERING FLOW REMAINS WEAK, ACCOUNTING FOR NEAR QUASISTATIONARY
MOTION. THE DEEP LAYER SUBTROPICAL RIDGE IS FORECAST TO STRENGTHEN
TO THE EAST AND BECOME THE PRIMARY STEERING MECHANISM AFTER 36
HOURS. THE CYCLONE WILL TRACK POLEWARD ALONG ITS WESTERN PERIPHERY.
AN UPPER LEVEL TROUGH WILL DEEPEN AND DIG INTO THE SUB-TROPICS BY
DAY 4 OF THE FORECAST AND WILL ACCOUNT FOR MARKED SOUTHEASTWARD
ACCELERATION. AROUND THIS TIME SEA SURFACE TEMPERATURES WILL COOL
AND VERTICAL WIND SHEAR WILL ELEVATE, INITIATING EXTRATROPICAL
TRANSITION. BY TAU 120 THE SYSTEM WILL HAVE LOST MOST OF ITS
TROPICAL CHARACTERISTICS AS IT INTERACTS WITH A BAROCLINIC BOUNDARY
NEAR NORTHERN NEW ZEALAND. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
190600Z IS 16 FEET. NEXT WARNINGS AT 192100Z AND 200900Z.//
=========================================================================
WTPS31 PGTW 20110219 21:00z
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 003//
RMKS/
1. TROPICAL CYCLONE 17P (ATU) 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:
191800Z --- NEAR 16.7S 169.1E
MOVEMENT PAST SIX HOURS - 160 DEGREES AT 03 KTS
POSITION ACCURATE TO WITHIN 060 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 - 075 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
REPEAT POSIT: 16.7S 169.1E
---
FORECASTS:
12 HRS, VALID AT:
200600Z --- 17.0S 169.2E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
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 - 080 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 170 DEG/ 03 KTS
---
24 HRS, VALID AT:
201800Z --- 17.5S 169.3E
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 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 - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 170 DEG/ 05 KTS
---
36 HRS, VALID AT:
210600Z --- 18.4S 169.5E
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 - 045 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 165 DEG/ 08 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
211800Z --- 19.9S 169.9E
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 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
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 155 DEG/ 11 KTS
---
72 HRS, VALID AT:
221800Z --- 23.8S 171.7E
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
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 - 045 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 140 DEG/ 22 KTS
---
LONG RANGE OUTLOOK:
NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 250 NM
ON DAY 4 AND 350 NM ON DAY 5... AND FOR INTENSITY
NEAR 20 KT EACH DAY.
---
96 HRS, VALID AT:
231800Z --- 30.7S 178.1E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
192100Z POSITION NEAR 16.8S 169.1E.
TROPICAL CYCLONE (TC) 17S, LOCATED APPROXIMATELY 485 NM WEST OF NADI,
FIJI, HAS TRACKED SOUTH-SOUTHEASTWARD AT 03 KNOTS OVER THE PAST SIX
HOURS. ANIMATED INFRARED SATELLITE IMAGERY SHOWS TIGHTLY CURVED
CONVECTIVE BANDING WRAPPING INTO A WELL-DEFINED LOW LEVEL CIRCULATION
CENTER (LLCC) WITH DEEP CENTRAL CONVECTION. A 191731Z SSMI MICROWAVE
IMAGE DEPICTS A SYMMETRIC MICROWAVE EYE WITH A CONCENTRIC EYE-WALL
AND CONFIRMS THE CURRENT POSITION WITH GOOD CONFIDENCE. ENVIRONMENTAL
ANALYSIS INDICATES THAT THE SYSTEM IS LOCATED BENEATH AN UPPER LEVEL
OUTFLOW SOURCE, IN A REGION OF MODERATE VERTICAL WIND SHEAR (20 TO 25
KNOTS) AND FAVORABLE SEA SURFACE TEMPERATURES. ANIMATED WATER VAPOR
IMAGERY SHOWS EXCELLENT EQUATORWARD AND EASTWARD OUTFLOW, HOWEVER
POLEWARD OUTFLOW IS SOMEWHAT HINDERED DUE TO SUBSIDENCE ASSOCIATED
WITH A PASSING SHORT-WAVE MID-LATITUDE TROUGH. TC 17S IS CURRENTLY IN
A WEAK STEERING ENVIRONMENT BETWEEN TWO DEEP-LAYERED SUBTROPICAL
RIDGES (STR) WHICH WILL CAUSE GENERALLY SLOW AND SOUTH-SOUTHEASTERLY
MOVEMENT THROUGH TAU 36. AS AN APPROACHING HIGH-AMPLITUDE
MID-LATITUDE TROUGH WEAKENS THE STR TO THE SOUTHWEST, THE STR TO THE
NORTHEAST WILL BECOME THE DOMINATE STEERING RIDGE AND THE SYSTEM WILL
BEGIN TO ACCELERATE AHEAD OF THE PASSING TROUGH. POLEWARD OUTFLOW IS
EXPECTED TO IMPROVE AHEAD OF THE PASSING TROUGH, ALLOWING THE SYSTEM
TO STEADILY INTENSIFY, WHILE IT CONTINUES TO TRACK OVER FAVORABLE
SSTS UNTIL AROUND 28 DEGREES SOUTH LATITUDE. TC ATU IS FORECAST TO
BEGIN INTERACTION WITH THE MID-LATITUDE WESTERLIES BY TAU 96, AND
COMPLETE EXTRA-TROPICAL TRANSITION AS A STORM FORCE LOW BY TAU 120.
NUMERICAL MODEL GUIDANCE IS SLIGHTLY SPREAD IN THE EARLY TAUS, DUE TO
THE WEAK STEERING PATTERN, BUT BECOME TIGHTLY CLUSTERED AS THE HIGH
AMPLITUDE TROUGH PUSHES THROUGH IN THE LATER TAUS. THIS FORECAST IS
SLIGHTLY EAST OF CONSENSUS TO ACCOUNT FOR WBAR, WHICH APPEARS TO BE
MIS-ANALYZING THE TIMING AND STRENGTH OF THE HIGH-AMPLITUDE TROUGH
PATTERN, BUT REMAINS WITHIN THE DYNAMIC AIDS ENVELOPE. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 191800Z IS 19 FEET.
NEXT WARNINGS AT 200900Z AND 202100Z.//
=========================================================================
WTPS31 PGTW 20110220 09:00z
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 004//
RMKS/
1. TROPICAL CYCLONE 17P (ATU) 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:
200600Z --- NEAR 17.0S 169.6E
MOVEMENT PAST SIX HOURS - 120 DEGREES AT 04 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 - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT
140 NM SOUTHEAST QUADRANT
135 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
REPEAT POSIT: 17.0S 169.6E
---
FORECASTS:
12 HRS, VALID AT:
201800Z --- 17.5S 170.1E
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 - 060 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT
140 NM SOUTHEAST QUADRANT
135 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 155 DEG/ 04 KTS
---
24 HRS, VALID AT:
210600Z --- 18.3S 170.5E
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 - 065 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 155 NM NORTHEAST QUADRANT
145 NM SOUTHEAST QUADRANT
140 NM SOUTHWEST QUADRANT
135 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 160 DEG/ 09 KTS
---
36 HRS, VALID AT:
211800Z --- 20.0S 171.1E
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 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 - 070 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT
150 NM SOUTHEAST QUADRANT
145 NM SOUTHWEST QUADRANT
140 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 165 DEG/ 08 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
220600Z --- 21.5S 171.6E
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 - 065 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 155 NM NORTHEAST QUADRANT
145 NM SOUTHEAST QUADRANT
140 NM SOUTHWEST QUADRANT
135 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 150 DEG/ 15 KTS
---
72 HRS, VALID AT:
230600Z --- 26.8S 175.1E
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
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 - 055 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT
135 NM SOUTHEAST QUADRANT
130 NM SOUTHWEST QUADRANT
125 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 140 DEG/ 26 KTS
---
LONG RANGE OUTLOOK:
NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 250 NM
ON DAY 4 AND 350 NM ON DAY 5... AND FOR INTENSITY
NEAR 20 KT EACH DAY.
---
96 HRS, VALID AT:
240600Z --- 34.4S 176.8W
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
200900Z POSITION NEAR 17.1S 169.7E.
TROPICAL CYCLONE (TC) 17P (ATU), LOCATED APPROXIMATELY 455 NM WEST
OF NADI, FIJI, HAS TRACKED EAST-SOUTHEASTWARD AT 04 KNOTS OVER THE
PAST SIX HOURS. THE SYSTEM HAS STRENGTHENED TO 90 KNOTS SINCE
YESTERDAY BASED ON 06Z DVORAK ESTIMATES FROM PGTW, PHFO, AND NFFN
RANGING FROM OF T4.5 TO T5.0. THE PEAK INTENSITY HAS BEEN ADJUSTED
UPWARD ON ACCOUNT OF THE CURRENT INTENSITY. AN EMBEDDED CENTER
WITHIN A LARGE CENTRAL DENSE OVERCAST HAS AIDED IN POSITIONING. THE
DEEP LAYER SUBTROPICAL RIDGE TO THE EAST OF TC ATU CONTINUES TO
STRENGTHEN AND WILL BECOME THE MAIN STEERING MECHANISM FOR THE
DURATION OF THE FORECAST. SLOW TO STEADY INTENSIFICATION IS LIKELY
OVER THE NEXT 2 DAYS DUE TO LOW VERTICAL WIND SHEAR, STRONG RADIAL
OUTFLOW ALOFT, AND WARM WATERS. AFTER TAU 48 ATU WILL BEGIN TO
WEAKEN AS SEA SURFACE TEMPERATURES COOL AND VERTICAL WIND SHEAR
ELEVATES IN ADVANCE OF AN UPPER LEVEL TROUGH. THIS TROUGH WILL ALSO
INCITE POLEWARD ACCELERATION. AN ACCOMPANYING BAROCLINIC ZONE WILL
INITIATE EXTRATROPICAL TRANSITION NEAR TAU 72 AND BY TAU 96, THE
LAST FORECAST POSITION, THE SYSTEM WILL BE FULLY EXTRATROPICAL.
MODEL GUIDANCE IS IN EXCEPTIONAL AGREEMENT REGARDING TRACK. AS SUCH
THE FORECAST LIES CLOSE TO THE MODEL CONSENSUS. MAXIMUM SIGNIFICANT
WAVE HEIGHT AT 200600Z IS 23 FEET. NEXT WARNINGS AT 202100Z AND
210900Z.//
=========================================================================
WTPS31 PGTW 20110220 21:00z
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 005//
RMKS/
1. TROPICAL CYCLONE 17P (ATU) 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:
201800Z --- NEAR 17.4S 169.7E
MOVEMENT PAST SIX HOURS - 150 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT
165 NM SOUTHEAST QUADRANT
140 NM SOUTHWEST QUADRANT
150 NM NORTHWEST QUADRANT
REPEAT POSIT: 17.4S 169.7E
---
FORECASTS:
12 HRS, VALID AT:
210600Z --- 18.4S 170.1E
MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT
175 NM SOUTHEAST QUADRANT
155 NM SOUTHWEST QUADRANT
160 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 160 DEG/ 08 KTS
---
24 HRS, VALID AT:
211800Z --- 19.9S 170.7E
MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT
175 NM SOUTHEAST QUADRANT
155 NM SOUTHWEST QUADRANT
160 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 160 DEG/ 12 KTS
---
36 HRS, VALID AT:
220600Z --- 22.2S 171.5E
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT
165 NM SOUTHEAST QUADRANT
140 NM SOUTHWEST QUADRANT
150 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 155 DEG/ 17 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
221800Z --- 25.3S 173.1E
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 155 NM NORTHEAST QUADRANT
160 NM SOUTHEAST QUADRANT
135 NM SOUTHWEST QUADRANT
140 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 140 DEG/ 21 KTS
---
72 HRS, VALID AT:
231800Z --- 31.4S 179.6E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 075 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT
170 NM SOUTHEAST QUADRANT
135 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 145 DEG/ 26 KTS
---
LONG RANGE OUTLOOK:
NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 250 NM
ON DAY 4 AND 350 NM ON DAY 5... AND FOR INTENSITY
NEAR 20 KT EACH DAY.
---
96 HRS, VALID AT:
241800Z --- 39.9S 173.0W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
202100Z POSITION NEAR 17.7S 169.8E.
TROPICAL CYCLONE (TC) 17P (ATU), LOCATED APPROXIMATELY 80 NM EAST-
NORTHEAST OF PORT VILA, VANUATU, HAS TRACKED SOUTH-SOUTHEASTWARD AT
04 KNOTS OVER THE PAST SIX HOURS. RECENT DVORAK T-NUMBER ESTIMATES
OF 6.0 FROM PGTW, PHFO, AND KNES INDICATE THAT THE MAXIMUM SUSTAINED
SURFACE WIND ASSOCIATED WITH THE CYCLONE HAS INCREASED TO AN
ESTIMATED 115 KNOTS. RECENT ANIMATED INFRARED SATELLITE IMAGERY
INDICATES FORMATION OF A 22 NM BANDING EYE FEATURE, ALSO EVIDENT IN
RECENT MICROWAVE SATELLITE IMAGERY. TC 17P IS TRACKING ALONG THE
WESTERN PERIPHERY OF A SUBTROPICAL RIDGE TO THE EAST. THIS RIDGE
WILL CONTINUE TO BUILD OVER THE NEXT FEW DAYS TO THE NORTHWEST OF
THE CYCLONE, STEERING THE SYSTEM GENERALLY SOUTH-SOUTHEASTWARD
THROUGH THE FORECAST PERIOD. AS A MID-LATITUDE TROUGH APPROACHES
FROM THE SOUTHWEST, TC 17P WILL ACCELERATE TOWARD THE BAROCLINIC
ZONE, PARTICULARLY AFTER TAU 36. BY TAU 72, INCREASING VERTICAL WIND
SHEAR AHEAD OF THE APPROACHING TROUGH, ENTRAINMENT OF DRIER AIR, AND
PASSAGE OVER A COOLER SEA SURFACE WILL INDUCE THE FIRST PHASE OF
EXTRATROPICAL TRANSITION. BY TAU 96 THE CYCLONE IS EXPECTED TO BE
FULLY EXTRATROPICAL, THROUGH STILL QUITE INTENSE DUE TO FAVORABLE
INTERACTION WITH THE MID-LATITUDE UPPER-LEVEL FLOW PATTERN. THE
NUMERICAL MODELS ARE IN GOOD AGREEMENT WITH THE CURRENT FORECAST,
WHICH LIES SLIGHTLY EAST OF AND FASTER THAN THE MODEL CONSENSUS.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 201800Z IS 31 FEET. NEXT WARNINGS
AT 210900Z AND 212100Z.//
=========================================================================
WTPS31 PGTW 20110221 09:00z
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 006//
RMKS/
1. TROPICAL CYCLONE 17P (ATU) 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 18.4S 170.3E
MOVEMENT PAST SIX HOURS - 135 DEGREES AT 07 KTS
POSITION ACCURATE TO WITHIN 030 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 095 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 175 NM NORTHEAST QUADRANT
160 NM SOUTHEAST QUADRANT
140 NM SOUTHWEST QUADRANT
155 NM NORTHWEST QUADRANT
REPEAT POSIT: 18.4S 170.3E
---
FORECASTS:
12 HRS, VALID AT:
211800Z --- 20.1S 171.0E
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT
175 NM SOUTHEAST QUADRANT
155 NM SOUTHWEST QUADRANT
160 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 160 DEG/ 12 KTS
---
24 HRS, VALID AT:
220600Z --- 22.4S 171.9E
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT
090 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT
175 NM SOUTHEAST QUADRANT
155 NM SOUTHWEST QUADRANT
160 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 160 DEG/ 16 KTS
---
36 HRS, VALID AT:
221800Z --- 25.3S 173.2E
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 085 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT
165 NM SOUTHEAST QUADRANT
140 NM SOUTHWEST QUADRANT
150 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 145 DEG/ 23 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
230600Z --- 29.1S 176.2E
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT
160 NM SOUTHEAST QUADRANT
135 NM SOUTHWEST QUADRANT
135 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 140 DEG/ 25 KTS
---
72 HRS, VALID AT:
240600Z --- 36.7S 176.0W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
210900Z POSITION NEAR 18.8S 170.5E.
TROPICAL CYCLONE (TC) 17P (ATU), LOCATED APPROXIMATELY 115 NM EAST-
SOUTHEAST OF PORT VILA, VANUATU, HAS TRACKED SOUTHEASTWARD AT 07
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS A WELL-DEFINED LOW-LEVEL CIRCULATION CENTER
WITH A BANDING EYE SUPPORTING THE CURRENT POSITION AND MOTION WITH
HIGH CONFIDENCE. OVER THE PAST 12 HOURS, THE SYSTEM HAS MAINTAINED
A SIMILAR STRUCTURE ON MICROWAVE IMAGERY (COMPARING THE 210549Z
=========================================================================
WTPS31 PGTW 20110221 21:00z
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 007//
RMKS/
1. TROPICAL CYCLONE 17P (ATU) 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:
211800Z --- NEAR 19.9S 171.1E
MOVEMENT PAST SIX HOURS - 150 DEGREES AT 09 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 110 NM NORTHEAST QUADRANT
115 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 175 NM NORTHEAST QUADRANT
185 NM SOUTHEAST QUADRANT
140 NM SOUTHWEST QUADRANT
155 NM NORTHWEST QUADRANT
REPEAT POSIT: 19.9S 171.1E
---
FORECASTS:
12 HRS, VALID AT:
220600Z --- 22.1S 172.0E
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 110 NM NORTHEAST QUADRANT
115 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT
190 NM SOUTHEAST QUADRANT
150 NM SOUTHWEST QUADRANT
160 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 155 DEG/ 17 KTS
---
24 HRS, VALID AT:
221800Z --- 25.1S 173.6E
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 110 NM NORTHEAST QUADRANT
115 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 180 NM NORTHEAST QUADRANT
190 NM SOUTHEAST QUADRANT
165 NM SOUTHWEST QUADRANT
170 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 145 DEG/ 21 KTS
---
36 HRS, VALID AT:
230600Z --- 28.4S 176.4E
MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 100 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT
185 NM SOUTHEAST QUADRANT
140 NM SOUTHWEST QUADRANT
150 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 135 DEG/ 24 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
231800Z --- 31.8S 179.8W
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT
160 NM SOUTHEAST QUADRANT
130 NM SOUTHWEST QUADRANT
135 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 145 DEG/ 24 KTS
---
72 HRS, VALID AT:
241800Z --- 39.1S 172.4W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
212100Z POSITION NEAR 20.5S 171.3E.
TROPICAL CYCLONE (TC) 17P (ATU), LOCATED APPROXIMATELY 295 NM EAST-
NORTHEAST OF NOUMEA, NEW CALEDONIA, HAS TRACKED SOUTHEASTWARD AT 09
KNOTS OVER THE PAST SIX HOURS. THE CURRENT POSITION ESTIMATE IS
BASED ON SATELLITE FIXES FROM VARIOUS REPORTING AGENCIES AND A
211701Z SSMI IMAGE. THE CURRENT INTENSITY OF 95 KNOTS IS CONSISTENT
WITH DVORAK INTENSITY T-NUMBER ESTIMATES RANGING FROM 90 TO 102
KNOTS. TC 17P HAS UNDERGONE SOME STRUCTURAL CHANGE OVER THE PAST
TWELVE HOURS, WITH EROSION OF THE SOUTHWESTERN PORTION OF THE
EYEWALL NOW EVIDENT IN INFRARED SATELLITE IMAGERY. THESE STRUCTURAL
CHANGES HAVE RESULTED IN SLIGHT WEAKENING. HOWEVER, THE CYCLONE IS
EXPECTED TO MAINTAIN INTENSITY OR INTENSIFY A BIT OVER THE UPCOMING
24 HOURS AS STRONG UPPER LEVEL OUTFLOW AND PASSAGE OVER A WARM SEA
SURFACE ARREST THE CURRENT WEAKENING TREND. TC 17P IS TRACKING ALONG
THE WESTERN PERIPHERY OF A SUBTROPICAL STEERING RIDGE TO THE EAST
AND IS EXPECTED TO ACCELERATE DURING THE FORECAST PERIOD AHEAD OF A
MID-LATITUDE TROUGH APPROACHING FROM THE SOUTHWEST. INCREASING
VERTICAL WIND SHEAR, ENTRAINMENT OF DRIER AIR, AND PASSAGE OVER
COOLER WATER WILL INDUCE THE FIRST PHASE OF EXTRATROPICAL TRANSITION
BY TAU 36. FAVORABLE INTERACTION WITH THE UPPER LEVEL FLOW PATTERN
AHEAD OF THE APPROACHING TROUGH WILL ENABLE TC 17P TO TRANSITION
INTO A STRONG EXTRATROPICAL LOW BY TAU 72. THE NUMERICAL MODEL
GUIDANCE REMAINS IN VERY GOOD AGREEMENT. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 211800Z IS 33 FEET. NEXT WARNINGS AT 220900Z AND 222100Z.//
=========================================================================
WTPS31 PGTW 20110222 09:00z
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 008//
RMKS/
1. TROPICAL CYCLONE 17P (ATU) 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:
220600Z --- NEAR 22.7S 172.1E
MOVEMENT PAST SIX HOURS - 170 DEGREES AT 15 KTS
POSITION ACCURATE TO WITHIN 045 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 100 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 175 NM NORTHEAST QUADRANT
190 NM SOUTHEAST QUADRANT
160 NM SOUTHWEST QUADRANT
165 NM NORTHWEST QUADRANT
REPEAT POSIT: 22.7S 172.1E
---
FORECASTS:
12 HRS, VALID AT:
221800Z --- 25.6S 173.7E
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT
180 NM SOUTHEAST QUADRANT
150 NM SOUTHWEST QUADRANT
155 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 145 DEG/ 19 KTS
---
24 HRS, VALID AT:
230600Z --- 28.6S 176.3E
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
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 - 080 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 155 NM NORTHEAST QUADRANT
170 NM SOUTHEAST QUADRANT
140 NM SOUTHWEST QUADRANT
145 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 140 DEG/ 23 KTS
---
36 HRS, VALID AT:
231800Z --- 32.0S 180.0E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT
155 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 135 DEG/ 27 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
240600Z --- 35.8S 175.5W
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
220900Z POSITION NEAR 23.4S 172.5E.
TROPICAL CYCLONE (TC) 17P (ATU), LOCATED APPROXIMATELY 315 NM EAST
OF NOUMEA, NEW CALEDONIA, HAS TRACKED SOUTHWARD AT 15 KNOTS OVER THE
PAST SIX HOURS. THERE IS HIGH CONFIDENCE IN THE CURRENT POSITION AND
MOTION BASED ON THE 35-NM EYE EVIDENT IN VISIBLE IMAGERY. THE
CURRENT INTENSITY OF 95 KNOTS IS BASED ON AN AVERAGE OF DVORAK
INTENSITY ESTIMATES RANGING FROM 90 TO 102 KNOTS. TC 17P HAS
MAINTAINED INTENSITY OVER THE PAST 06 HOURS WITH LITTLE STRUCTURAL
CHANGE. A 220532Z SSMI IMAGE DEPICTS STRONG CONVECTIVE BANDING OVER
ALL QUADRANTS. TC 17P IS ACCELERATING ALONG THE WESTERN PERIPHERY OF
A SUBTROPICAL STEERING RIDGE TO THE EAST AND IS EXPECTED TO TRACK
SOUTHEASTWARD THROUGH THE FORECAST PERIOD. TC 17P SHOULD BEGIN EXTRA-
TROPICAL TRANSITION (ETT) NEAR TAU 24 AS IT BEGINS TO INTERACT WITH
A MID-LATITUDE TROUGH APPROACHING FROM THE SOUTHWEST. INCREASING
VERTICAL WIND SHEAR, ENTRAINMENT OF DRIER AIR, AND PASSAGE OVER
COOLER WATER WILL RESULT IN RAPID WEAKENING AFTER TAU 24. THE SYSTEM
IS EXPECTED TO COMPLETE ETT BY TAU 48 AND SHOULD REMAIN A STRONG
EXTRATROPICAL LOW. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 220600Z IS 35
FEET. NEXT WARNINGS AT 222100Z AND 230900Z.//
=========================================================================
WTPS31 PGTW 20110222 21:00z
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 009//
RMKS/
1. TROPICAL CYCLONE 17P (ATU) 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:
221800Z --- NEAR 25.4S 173.7E
MOVEMENT PAST SIX HOURS - 150 DEGREES AT 17 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 - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT
180 NM SOUTHEAST QUADRANT
150 NM SOUTHWEST QUADRANT
155 NM NORTHWEST QUADRANT
REPEAT POSIT: 25.4S 173.7E
---
FORECASTS:
12 HRS, VALID AT:
230600Z --- 28.7S 176.1E
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT
180 NM SOUTHEAST QUADRANT
150 NM SOUTHWEST QUADRANT
155 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 135 DEG/ 20 KTS
---
24 HRS, VALID AT:
231800Z --- 31.4S 179.6E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
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 - 075 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT
160 NM SOUTHEAST QUADRANT
130 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 135 DEG/ 20 KTS
---
36 HRS, VALID AT:
240600Z --- 34.1S 176.9W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
222100Z POSITION NEAR 26.2S 174.3E.
TROPICAL CYCLONE (TC) 17P (ATU), LOCATED APPROXIMATELY 500 NM SOUTH-
SOUTHWEST OF NADI, FIJI, HAS TRACKED SOUTH-SOUTHEASTWARD AT 17 KNOTS
OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY SHOWS A
14 NM EYE WITH DEGRADED CONVECTION ALONG THE SOUTHWESTERN PERIPHERY.
A 221644Z SSMI IMAGES DEPICTS DEEP CONVECTIVE BANDING HAS DECREASED
ALONG THE NORTHWEST QUADRANT DUE TO SUBSIDENCE ALOFT. OUTFLOW IS
ALSO HINDERED ON THIS SIDE ALTHOUGH POLEWARD OUTFLOW REMAINS GOOD.
THE CURRENT INTENSITY IS BASED ON AN AVERAGE OF PGTW, PHFO, AND NFFN
DVORAK ESTIMATES RANGING FROM 77 TO 102 KNOTS. TC 17P IS
ACCELERATING ALONG THE SOUTHWESTERN PERIPHERY OF A SUBTROPICAL
STEERING RIDGE AND WILL CONTINUE TRACKING OVER COOLER WATERS (BELOW
26 DEGREES CELSIUS) DURING THE NEXT 12 HOURS. DUE TO THE COOLER
WATERS COUPLED WITH INCREASED VERTICAL WIND SHEAR ASSOCIATED WITH
THE MID-LATITUDE TROUGH TO THE SOUTHWEST, TC 17P WILL WEAKEN AND
TRANSITION INTO A STRONG EXTRA-TROPICAL LOW BY TAU 36. NUMERICAL
MODEL GUIDANCE IS IN EXCELLENT AGREEMENT. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 221800Z IS 33 FEET. NEXT WARNINGS AT 230900Z AND 232100Z.//
=========================================================================
WTPS31 PGTW 20110223 09:00z
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 010//
RMKS/
1. TROPICAL CYCLONE 17P (ATU) 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:
230600Z --- NEAR 28.5S 176.5E
MOVEMENT PAST SIX HOURS - 135 DEGREES AT 22 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY A COMBINATION OF
SATELLITE AND RADAR
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
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 - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT
140 NM SOUTHEAST QUADRANT
140 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
REPEAT POSIT: 28.5S 176.5E
---
FORECASTS:
12 HRS, VALID AT:
231800Z --- 31.4S 179.6W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
145 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
125 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 130 DEG/ 23 KTS
---
24 HRS, VALID AT:
240600Z --- 34.2S 175.3W
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
230900Z POSITION NEAR 29.2S 177.5E.
TROPICAL CYCLONE (TC) 17P (ATU), LOCATED APPROXIMATELY 505 NM
NORTH-NORTHEAST OF AUCKLAND, NEW ZEALAND, HAS ACCELERATED
SOUTHEASTWARD AT 22 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTI-SPECTRAL SATELLITE IMAGERY AND A 230515Z 85H SSMI MICROWAVE
IMAGE DEPICT A 14 NM RAGGED EYE WITH EXPOSED LOW LEVEL BANDING ALONG
THE NORTHWESTERN QUADRANT AND WEAKENING DEEP CONVECTION EXTENDING
INTO THE SOUTHERN QUADRANTS (INDICATIVE OF THE ONSET OF
EXTRA-TROPICAL TRANSITION). THE CURRENT INTENSITY IS BASED ON DVORAK
FINAL-T AND CURRENT INTENSITY ESTIMATES RANGING FROM 65 TO 77 KNOTS
FROM PGTW AND KNES. TC 17P IS CURRENTLY UNDERGOING EXTRA-TROPICAL
TRANSITION (ET) AND IS EXPECTED TO COMPLETE ET BY 24/06Z AS IT
CONTINUES TO ACCELERATE ALONG THE SOUTHWESTERN PERIPHERY OF A
SUBTROPICAL STEERING RIDGE INTO THE MID-LATITUDE WESTERLIES. TC 17P
WILL SLOWLY WEAKEN AS IT ENCOUNTERS INCREASED VERTICAL WIND SHEAR AND
COOLER SSTS, BUT SHOULD COMPLETE ET AS A STRONG EXTRA-TROPICAL LOW.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 230600Z IS 30 FEET. NEXT WARNINGS
AT 232100Z.//
=========================================================================
WTPS31 PGTW 20110223 21:00z
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 011//
RMKS/
1. TROPICAL CYCLONE 17P (ATU) 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:
231800Z --- NEAR 31.4S 179.9E
MOVEMENT PAST SIX HOURS - 135 DEGREES AT 22 KTS
POSITION ACCURATE TO WITHIN 060 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
BECOMING EXTRATROPICAL
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 - 120 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
REPEAT POSIT: 31.4S 179.9E
---
FORECASTS:
12 HRS, VALID AT:
240600Z --- 33.7S 175.6W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
232100Z POSITION NEAR 32.0S 179.0W.
TROPICAL CYCLONE (TC) 17P (ATU), LOCATED APPROXIMATELY 415 NM
NORTHEAST OF AUCKLAND, NEW ZEALAND, HAS TRACKED SOUTHEASTWARD AT
22 KNOTS OVER THE PAST SIX HOURS. ANIMATED WATER VAPOR IMAGERY SHOWS
THE SYSTEM HAS SIGNIFICANTLY ACCELERATED AND IS NOW EMBEDDED IN THE
UPPER LEVEL WESTERLIES. ADDITIONALLY, THE LOW LEVEL CIRCULATION
CENTER IS SHEARED TO THE WEST OF THE MAIN CONVECTION. COLD AIR
ADVECTION IS EVIDENT ON THE SOUTHWEST FLANK WITH LINES OF STRATO-
CUMULUS CLOUDS ADVANCING INTO THE LLCC. THE SYSTEM IS BEGINNING TO
EXHIBIT EXTRA-TROPICAL (ET) CHARACTERISTICS AND IS EXPECTED TO BECOME
FULL ET IN 12 APPROXIMATELY HOURS. THIS IS SUPPORTED BY ET PROGNOSTIC
MODELS. THIS IS THE FINAL WARNING ON THIS SYSTEM BY THE JOINT TYPHOON
WARNING CENTER (NAVMARFCSTCEN). THE SYSTEM WILL BE CLOSELY MONITORED
FOR SIGNS OF REGENERATION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 231800Z
IS 27 FEET.//
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| Document: tropical_cyclone_atu.htm | Updated: 24 February 2011 |