The TD near Vanuatu looks to have become fairly well organised overnight...
Tropical Disturbance Summary For area Equator to 25S, 160E to 120W
ISSUED FROM RSMC NADI Feb 17/0909 UTC 2011 UTC.
TROPICAL DEPRESSION TD11F [1002 HPA] ANALYSED NEAR 13.8S 169.9E AT
170600 UTC SLOW MOVING. POSITION POOR BASED ON MTSAT IR IMAGERY WITH
ANIMATION AND PERIPHERAL OBSERVATIONS. SST AROUND 30 DEGREES.
ORGANISATION HAS SLIGHTLY IMPROVED. DEEP CONVECTION HAS DECREASED IN
THE LAST 6 HOURS DUE TO DIURNAL VARIATION. CYCLONIC CIRCULATION
EXTENDS TO 500HPA. SYSTEM LIES UNDER AN UPPER RIDGE IN A MODERATELY
SHEARED ENVIRONMENT.
GLOBAL MODELS HAVE PICKED UP THE SYSTEM AND GRADUALLY MOVE IT
SOUTH-SOUTHEAST WITH SOME INTENSIFICATION.
THE POTENTIAL FOR THIS SYSTEM TO DEVELOP INTO A TROPICAL CYCLONE IN
THE NEXT 24 TO 48 HOURS IS MODERATE TO HIGH.
ABPW10 PGTW 170600
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND
/SOUTH PACIFIC OCEANS/170600Z-180600ZFEB2011//
RMKS/
--- (1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 13.5S
170.8E, IS NOW LOCATED NEAR 14.0S 170.9E, APPROXIMATELY 440 NM WEST-
NORTHWEST OF NADI, FIJI. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
DEPICTS DISORGANIZED, FLARING DEEP CONVECTION OVER THE LOW-LEVEL
CIRCULATION CENTER (LLCC). A 162152Z METOP-A IMAGE SHOWS WEAK
CONVECTIVE BANDING OVER THE SOUTH QUADRANT. THE 162205Z ASCAT IMAGE
INDICATES A SYMMETRIC, WELL-DEFINED LLCC WITH 15-20 KNOT WINDS
SURROUNDING THE CENTER. UPPER-LEVEL ANALYSIS INDICATES THAT THE LLCC
IS LOCATED JUST TO THE NORTH OF AN ANTICYCLONE WITH WEAK VERTICAL
WIND SHEAR. ANIMATED WATER VAPOR IMAGERY SHOWS OVERALL GOOD OUTFLOW.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1004 MB. BASED ON
THE LACK OF SIGNIFICANT CONVECTIVE BANDING AND THE RELATIVELY WEAK
SURFACE WINDS, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS POOR.
(2) NO OTHER SUSPECT AREAS.//
NNNN
You do not have the required permissions to view the files attached to this post.
Looks as though it could become quite a powerful cyclone for a time...unsure if it will be huge in size just yet, but judging by the models it could be intense. Certainly has good sea surface temps and the right upper atmopsheric conditions this weekend.
TD near Vanuatu looking very well organised this morn...
TROPICAL DISTURBANCE ADVISORY NUMBER A4 ISSUED FROM RSMC NADI
Feb 18/1946 UTC 2011 UTC.
TROPICAL DEPRESSION 11F CENTRE 997 HPA WAS LOCATED NEAR 15.6S 169.6E
AT 181800 UTC.
POSITION POOR BASED ON MTSAT IR IMAGERY AND PERIPHERAL SURFACE
OBSERVATIONS. DEPRESSION SLOW MOVING. MAXIMUM 10-MINUTE AVERAGE
WINDS NEAR THE CENTRE ESTIMATED AT ABOUT 30 KNOTS.
ORGANISATION IMPROVED PAST 24 HOURS WITH PRIMARY BANDS TRYING TO WRAP
AROUND LLCC. CONVECTION HAS INCREASED PAST 12 HOURS DUE TO DIURNAL
VARIATION MAKING LLCC CLOUD FILLED. CYCLONIC CIRCULATION EXTENDS TO
500HPA. SST AROUND 30 DEGREE CELSIUS. SYSTEM LIES ALONG A SURFACE
TROUGH UNDER AN UPPER DIFFLUENT REGION IN A MODERATE SHEARED
ENVIRONMENT. SYSTEM IS BEING STEERED SOUTH-SOUTHEAST BY A WEAK
NORTHWEST DEEP LAYER MEAN REGIME. MID-LEVEL RIDGE TO SOUTH OF SYSTEM
IS EXPECTED TO WEAKEN AND RECEDE TO THE WEST AS SYSTEM MOVES SOUTH.
DVORAK ASSESMENT BASED ON 0.40 WRAP ON LOG 10 SPIRAL YIELDING DT=2.5,
MET=2.5 PT=2.5 FT BASED ON DT, THUS T2.5/2.5/D1.0/24HRS.
GLOBAL MODELS ARE GRADUALLY DEVELOPING THE DEPRESSION AND MAINTAINING
A SSE TRACK. POTENTIAL FOR THE SYSTEM TO DEVELOP INTO A TROPICAL
CYCLONE IN THE NEXT 24 HOURS IS HIGH.
FORECAST:
AT 12 HRS VALID AT 190600 UTC 16.3S 169.6E MOV S AT 04 KT WITH 35 KT
CLOSE TO CENTRE
AT 24 HRS VALID AT 191800 UTC 17.0S 169.7E MOV SSE AT 03 KT WITH 40
KT CLOSE TO CENTRE
OUTLOOK :
AT 36 HRS VALID AT 200600 UTC 17.5S 170.0E MOV SSE AT 03 KT WITH 45
KT CLOSE TO CENTRE
AT 48 HRS VALID AT 201800 UTC 18.1S 170.4E MOV SSE AT 04 KT WITH 50
KT CLOSE TO CENTRE
THE NEXT TROPICAL DISTURBANCE ADVISORY ON TD 11F WILL BE ISSUED AT
AROUND 190200 UTC OR EARLIER.
JTWC issued an alert yesterday evening, which seem to have disappeared this morn? ...
WTPS21 PGTW 180530
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.
You do not have the required permissions to view the files attached to this post.
JTWC have now recognised our former TD 90P as TC 17P...
WTPS31 PGTW 182100
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
---
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.
You do not have the required permissions to view the files attached to this post.
TC Atu was finally named by RSMC Nadi this arvo...
GALE WARNING 009 ISSUED FROM RSMC NADI Feb 19/0322 UTC 2011 UTC.
TROPICAL CYCLONE ATU CENTRE 995HPA CATEGORY 1 WAS LOCATED NEAR 16.0
SOUTH 169.3 EAST AT 190100UTC. POSITION FAIR.
REPEATED POSITION 16.0S 169.3E AT 190100 UTC.
CYCLONE MOVING SOUTHWEST AT 04 KNOTS. CYCLONE INTENSIFYING.
EXPECT SUSTAINED WINDS OF 35 KNOTS CLOSE TO THE CENTRE INCREASING TO
45 KNOTS BY 200100 UTC.
EXPECT WINDS OVER 33 KNOTS WITHIN 180 NAUTICAL MILES IN NE QUADRANT
60 NAUTICAL MILES IN SE QUADRANT 40 NAUTICAL MILES IN SW QUADRANT AND
60 NAUTICAL MILES IN NW QUADRANT.
FORECAST POSITION NEAR 16.8S 169.2E AT 191300 UTC
AND NEAR 17.4S 169.4E AT 200100 UTC.
ALL VESSELS WITHIN 300 NAUTICAL MILES OF CENTRE ARE REQUESTED TO SEND
REPORTS EVERY THREE HOURS TO RSMC NADI. VOS REPORTING SHIPS USE
NORMAL CHANNELS. OTHER VESSELS FAX PLUS 679 6720190 OR EMAIL NADITCC
AT MET DOT GOV DOT FJ.
TROPICAL DISTURBANCE ADVISORY NUMBER A7 ISSUED FROM RSMC NADI
Feb 19/1406 UTC 2011 UTC.
TROPICAL CYCLONE ATU CENTRE 987HPA CAT 1 WAS LOCATED NEAR 16.4S
168.7E AT 191200 UTC. POSITION POOR BASED ON MTSAT EIR IMAGERY AND
PERIPHERAL SURFACE OBSERVATIONS. CYCLONE MOVING SOUTH-SOUTHWEST AT
ABOUT 4 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 45 KNOTS INCREASING TO 55 KNOTS BY 200000
UTC.CYCLONE INTENSIFYING.
EXPECT WINDS OVER 33 KNOTS WITHIN 180 NAUTICAL MILES IN NE QUADRANT
AND WITHIN 100 NAUTICAL MILES IN SE QUADRANT AND WITHIN 20 NAUTICAL
MILES IN SW QUADRANT AND WITHIN 20 NAUTICAL MILES IN NW QUADRANT.
ORGANISATION IMPROVED IN THE LAST 24 HOURS. CONVECTION HAS INCREASED
PAST 6 HOURS WITH CLOUD TOPS COOLING. CYCLONIC CIRCULATION EXTENDS TO
500 HPA. SST AROUND 29 DEGREES CELCIUS. SYSTEM LIES ALONG A SURFACE
TROUGH UNDER AN UPPER DIFFLUENT REGION IN A WEAK SHEARED ENVIRONMENT.
CIMMS INDICATES DECREASING SHEAR ALONG FORECAST PATH. SYSTEM IS BEING
STEERED SOUTH BY A WEAK NORHTERLY DEEP LAYER MEAN WIND. DVORAK
ASSESSMENT BASED ON 0.75 WRAP ON LOG 10 SPIRAL YIELDING DT = 3.0,
MET=3.0 PT=3.0, FT BASED ON DT, THUS T3.0/3.0/D1.0/24HRS.
GLOBAL MODELS ARE GRADUALLY INTENSIFYING THE SYSTEM AND MOVING IT
SOUTH THEN SOUTH-SOUTHEASTWARDS.
FORECASTS :
AT 12 HRS VALID AT 200000 UTC 17.0S 168.7E MOV S AT 03 KT WITH 55 KT
CLOSE TO CENTRE
AT 24 HRS VALID AT 201200 UTC 17.5S 169.1E MOV SSE AT 03 KT WITH 55
KT CLOSE TO CENTRE
OUTLOOK :
AT 36 HRS VALID AT 210000 UTC 18.2S 169.4E MOV SSE AT 04 KT WITH 60
KT CLOSE TO CENTRE
AT 48 HRS VALID AT 211200 UTC 19.4S 169.8E MOV SE AT 05 KT WITH 60 KT
CLOSE TO CENTRE
THE NEXT TROPICAL DISTURBANCE ADVISORY ON CYCLONE ATU WILL BE ISSUED
AROUND 192000 UTC.
WTPS31 PGTW 190900
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 002//
RMKS/
---
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
---
REMARKS:
190900Z POSITION NEAR 16.4S 169.0E.
TROPICAL CYCLONE (TC) 17P (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.//
NNNN
You do not have the required permissions to view the files attached to this post.
WTPS31 PGTW 192100
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 003//
RMKS/
---
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
---
REMARKS:
192100Z POSITION NEAR 16.8S 169.1E.
TROPICAL CYCLONE (TC) 17P, 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 17P 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.//
NNNN
TROPICAL DISTURBANCE ADVISORY NUMBER A8 ISSUED FROM RSMC NADI
Feb 19/1948 UTC 2011 UTC.
TROPICAL CYCLONE ATU CENTRE 987HPA CAT 1 WAS LOCATED NEAR 16.7S
169.2E AT 191800 UTC. POSITION POOR BASED ON MTSAT EIR IMAGERY AND
PERIPHERAL SURFACE OBSERVATIONS. CYCLONE MOVING SOUTH-SOUTHWEST AT
ABOUT 03 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 45 KNOTS INCREASING TO 55 KNOTS WITHIN THE NEXT 6
TO 12 HOURS. CYCLONE INTENSIFYING.
EXPECT WINDS OVER 33 KNOTS WITHIN 180 NAUTICAL MILES IN NE QUADRANT
AND WITHIN 100 NAUTICAL MILES IN SE QUADRANT AND WITHIN 35 NAUTICAL
MILES IN SW QUADRANT AND WITHIN 35 NAUTICAL MILES IN NW QUADRANT.
ORGANISATION IMPROVED IN THE LAST 24 HOURS. CONVECTION HAS INCREASED
PAST 6 HOURS WITH CLOUD TOPS COOLING. CYCLONIC CIRCULATION EXTENDS TO
500 HPA. SST AROUND 29 DEGREES CELCIUS. SYSTEM LIES ALONG A SURFACE
TROUGH UNDER AN UPPER DIFFLUENT REGION IN A WEAK SHEARED ENVIRONMENT.
CIMMS INDICATES DECREASING SHEAR ALONG FORECAST PATH. SYSTEM IS BEING
STEERED SOUTH BY A WEAK NORHTERLY DEEP LAYER MEAN WIND. DVORAK
ASSESSMENT BASED ON 0.75 WRAP ON LOG 10 SPIRAL YIELDING DT = 3.0,
MET=3.0 PT=3.0, FT BASED ON DT, THUS T3.0/3.0/D1.0/24HRS.
GLOBAL MODELS ARE INTENSIFYING THE SYSTEM AND MOVING IT
SOUTHEASTWARDS.
FORECASTS :
AT 12 HRS VALID AT 200600 UTC 17.3S 169.3E MOV S AT 03 KT WITH 55 KT
CLOSE TO CENTRE
AT 24 HRS VALID AT 201800 UTC 17.8S 169.5E MOV SSE AT 03 KT WITH 60
KT CLOSE TO CENTRE
OUTLOOK :
AT 36 HRS VALID AT 210600 UTC 18.6S 169.9E MOV SSE AT 03 KT WITH 60
KT CLOSE TO CENTRE
AT 48 HRS VALID AT 211800 UTC 19.9S 170.4E MOV SE AT 04 KT WITH 60 KT
CLOSE TO CENTRE
THE NEXT TROPICAL DISTURBANCE ADVISORY ON CYCLONE ATU WILL BE ISSUED
AROUND 200200 UTC.
You do not have the required permissions to view the files attached to this post.
TC Atu strengthened to a Cat 2 this arvo, with a fairly well defined visible eye for most of today...
HURRICANE WARNING 013 ISSUED FROM RSMC NADI Feb 20/0107 UTC 2011 UTC.
TROPICAL CYCLONE ATU CENTRE 980HPA CATEGORY 2 WAS LOCATED NEAR 16.8 SOUTH 169.2
EAST AT 200000 UTC.
POSITION FAIR.
REPEAT POSITION 16.8S 169.2E AT 200000 UTC.
CYCLONE SLOW MOVING. CYCLONE INTENSIFYING.
EXPECT SUSTAINED WINDS OF 55 KNOTS CLOSE TO THE CENTRE INCREASING TO 65 KNOTS IN
THE NEXT 12 TO 24 HOURS.
EXPECT WINDS OVER 47 KNOTS WITHIN 020 NAUTICAL MILES OF CENTRE AND
EXPECT WINDS OVER 33 KNOTS WITHIN 180 NAUTICAL MILES OF CENTRE IN NE QUADRANT
AND WITHIN 100 NAUTICAL MILES OF CENTRE IN SE QUADRANT
AND WITHIN 35 NAUTICAL MILES OF CENTRE IN SW QUADRANT
AND WITHIN 35 NAUTICAL MILES OF CENTRE IN NW QUADRANT.
FORECAST POSITION NEAR 17.2S 169.3E AT 201200 UTC
AND NEAR 17.9S 169.6E AT 210000 UTC.
ALL VESSELS WITHIN 300 NAUTICAL MILES OF CENTRE ARE REQUESTED TO SEND REPORTS
EVERY THREE HOURS TO RSMC NADI. VOS REPORTING SHIPS USE NORMAL CHANNELS. OTHER
VESSELS FAX PLUS 679 6720190 OR EMAIL NADITCC AT MET DOT GOV DOT FJ.
THIS WARNING CANCELS AND REPLACES WARNING 012.
You do not have the required permissions to view the files attached to this post.
HURRICANE WARNING 014 ISSUED FROM RSMC NADI Feb 20/0748 UTC 2011 UTC.
SEVERE TROPICAL CYCLONE ATU CENTRE 973HPA CATEGORY 3 WAS LOCATED NEAR 17.0 SOUTH
169.4 EAST AT 200600 UTC.
POSITION FAIR.
REPEAT POSITION 17.0S 169.4E AT 200600 UTC.
CYCLONE MOVING SOUTHEAST AT 3 KNOTS. CYCLONE INTENSIFYING RAPIDLY.
EXPECT SUSTAINED WINDS OF 70 KNOTS CLOSE TO THE CENTRE INCREASING TO 90 KNOTS BY
210600 UTC.
TROPICAL DISTURBANCE ADVISORY NUMBER A10 ISSUED FROM RSMC NADI
Feb 20/0842 UTC 2011 UTC.
SEVERE TROPICAL CYCLONE ATU CENTRE 973HPA CAT 3 WAS LOCATED NEAR
17.0S 169.4E AT 200600 UTC. POSITION POOR BASED ON MTSAT EIR AND VIS
IMAGERY AND PERIPHERAL SURFACE REPORTS. CYCLONE MOVING SOUTHEAST AT
ABOUT 3 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 70 KNOTS AND INCREASING TO 90 KNOTS IN THE NEXT 24
HOURS.
EXPECT WINDS OVER 63 KNOTS WITHIN 20 NAUTICAL MILES OF CENTRE, WINDS
OVER 47 KNOTS WITHIN 30 NAUTICAL MILES OF CENTRE AND OVER 33 KNOTS
WITHIN 180 NAUTICAL MILES IN NE QUADRANT 120 NAUTICAL MILES IN SE
QUADRANT 45 NAUTICAL MILES ELSEWHERE.
ATU INTENSIFIED RAPIDLY. ORGANISATION HAS IMPROVED SIGNIFICANTLY IN
THE LAST 24 HOURS. CONVECTION REMAINS PERSISTENT WITH CENTRE
EMBEDDED. OUTFLOW RESTRICTED TO THE WEST OF THE SYSTEM BUT GOOD
ELSEWHERE. CYCLONIC CIRCULATION EXTENDS TO 300 HPA. SST AROUND 29
DEGREES CELCIUS. SYSTEM LIES ALONG A SURFACE TROUGH UNDER AN UPPER
DIFFLUENT REGION. CIMSS INDICATES SYSTEM LYING IN A MODERATE SHEARED
ENVIRONMENT AND DECREASING SHEAR ALONG FORECAST PATH. SYSTEM IS BEING
STEERED SOUTH BY A WEAK NORHTERLY DEEP LAYER MEAN WIND. DVORAK
ASSESSMENT BASED ON EMBEDDED CENTRE PATTERN IN WHITE SURROUND
YIELDING DT = 5.0, MET =4.5 PT = 4.5, FT BASED ON MET, THUS
T4.5/4.5/D1.5/24HRS.
GLOBAL MODELS ARE GRADUALLY MOVING THE SYSTEM SOUTH-SOUTHEAST WITH
SOME INTENSIFICATION.
WTPS31 PGTW 200900
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 004//
---
WARNING POSITION:
200600Z --- NEAR 17.0S 169.6E
MOVEMENT PAST SIX HOURS - 120 DEGREES AT 04 KTS
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
---
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.//
You do not have the required permissions to view the files attached to this post.
Rapidly intensifying Atu declared Cat 4 very early this morn ... only about 36 hrs after being named.
HURRICANE WARNING 015 ISSUED FROM RSMC NADI Feb 20/1308 UTC 2011 UTC.
SEVERE TROPICAL CYCLONE ATU CATEGORY 4 CENTRE 940HPA WAS LOCATED NEAR 17.0 SOUTH
169.5 EAST AT 201200 UTC.
POSITION GOOD.
REPEAT POSITION 17.0S 169.5E AT 201200 UTC.
CYCLONE MOVING SOUTHEAST AT 3 KNOTS. CYCLONE INTENSIFYING.
EXPECT SUSTAINED WINDS OF 90 KNOTS CLOSE TO THE CENTRE INCREASING TO 100 KNOTS
BY 210000 UTC.
TROPICAL DISTURBANCE ADVISORY NUMBER A11 ISSUED FROM RSMC NADI
Feb 20/1358 UTC 2011 UTC.
SEVERE TROPICAL CYCLONE ATU CENTRE 940HPA CAT 4 WAS LOCATED NEAR
17.0S 169.5E AT 201200 UTC. POSITION GOOD BASED ON MTSAT EIR IMAGERY
AND PERIPHERAL SURFACE OBSERVATIONS. CYCLONE MOVING SOUTHEAST AT
ABOUT 3 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 90 KNOTS AND INCREASING TO 100 KNOTS BY 210000
UTC.
EXPECT WINDS OVER 63 KNOTS WITHIN 30 NAUTICAL MILES OF CENTRE OVER 47
KNOTS WITHIN 40 NAUTICAL MILES OF CENTRE AND OVER 33 KNOTS WITHIN 200
NAUTICAL MILES IN NE QUADRANT AND WITHIN 150 NAUTICAL MILES IN SE
QUADRANT AND WITHIN 80 NAUTICAL MILES IN SW QUADRANT AND WITHIN 60
NAUTICAL MILES IN NW QUADRANT.
TC ATU INTENSIFIED RAPIDLY PAST 12 HOURS. ORGANISATION HAS IMPROVED
SIGNIFICANTLY IN THE LAST 24 HOURS. EYE WELL DEFINED. ATU CONTINUES
TO INTENSIFY WITH EYE WARMING AND CONVECTIVE TOPS COOLING. OUTFLOW
GOOD. SST AROUND 29 DEGREES CELCIUS. SYSTEM LIES UNDER AN UPPER
DIFFLUENT REGION IN A WEAK SHEARED ENVIRONMENT. CIMSS INDICATES
DECREASING SHEAR ALONG FORECAST PATH. SYSTEM IS BEING STEERED
SOUTHEAST BY A WEAK NORHTWESTERLY DEEP LAYER MEAN WIND. DVORAK
ASSESSMENT BASED ON DG EYE W SURROUND YIELDING DT = 6.5, MET =5.0 PT
= 5.5, FT BASED ON PT, THUS T5.5/5.5/D2.0/24HRS.
GLOBAL MODELS ARE INTENSIFYING THE SYSTEM AND GRADUALLY MOVING IT
SOUTH-SOUTHEASTWARDS.
You do not have the required permissions to view the files attached to this post.
TROPICAL DISTURBANCE ADVISORY NUMBER A12 ISSUED FROM RSMC NADI
Feb 20/2032 UTC 2011 UTC.
SEVERE TROPICAL CYCLONE ATU CENTRE 940HPA CAT 4 WAS LOCATED NEAR
17.4S 169.7E AT 201800 UTC. POSITION GOOD BASED ON MTSAT EIR IMAGERY
AND PERIPHERAL SURFACE OBSERVATIONS. CYCLONE SLOW MOVING. MAXIMUM
10-MINUTE AVERAGE WINDS NEAR THE CENTRE ESTIMATED AT ABOUT 90 KNOTS
AND INCREASING TO 100 KNOTS WITHIN THE NEXT 6 TO 18 HOURS.
---
SYSTEM INTENSIFIED RAPIDLY PAST 12 HOURS. ORGANISATION HAS IMPROVED
SIGNIFICANTLY IN THE LAST 24 HOURS. EYE HAS BECOME CLOUD FILLED IN
PAST 3 HOURS. SYSTEM CONTINUES TO INTENSIFY WITH CONVECTIVE TOPS
COOLING. PRIMARY BANDS TO SOUTH AND WEST OF SYSTEM DISSIPATING DUE TO
DRY AIR ENTRAINMENT PAST 4 HOURS THOUGH THIS COULD ALSO BE PART
OF EYE WALL REPLACEMENT PROCESS. OUTFLOW GOOD TO SOUTH AND EAST AND
FAIR ESLEWHERE. SST AROUND 29C. SYSTEM LIES ALONG IN A WEAK SHEAR
ENVIRONMENT. CIMSS INDICATES DECREASING SHEAR ALONG FORECAST PATH.
SYSTEM IS BEING STEERED SOUTHEAST BY A WEAK NORHTWESTERLY DEEP LAYER
MEAN WIND. DVORAK ASSESSMENT BASED ON B EYE W SURROUND YIELDING
DT6.0, MET 5.5 PT 5.5, FT BASED ON PT, THUS T5.5/5.5/D2.0/24HRS.
GLOBAL MODELS ARE INTENSIFYING THE SYSTEM AND ARE MOVING IT
SOUTHEASTWARDS.
---
WTPS31 PGTW 202100
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 005//
---
WARNING POSITION:
201800Z --- NEAR 17.4S 169.7E
MOVEMENT PAST SIX HOURS - 150 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 040 NM
MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT
---
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.//
[EDIT: JTWC remarks updated]
You do not have the required permissions to view the files attached to this post.
Has weakened slightly this arvo, but probably not for long...
TROPICAL DISTURBANCE ADVISORY NUMBER A13 ISSUED FROM RSMC NADI
Feb 21/0216 UTC 2011 UTC.
SEVERE TROPICAL CYCLONE ATU CENTRE 940HPA CAT 4 WAS LOCATED NEAR
17.9S 169.9E AT 210000 UTC. POSITION GOOD BASED ON MTSAT EIR/VIS
IMAGERY AND PERIPHERAL SURFACE OBSERVATIONS. CYCLONE MOVING
SOUTH-SOUTHEAST AT 03 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR
THE CENTRE ESTIMATED AT ABOUT 90 KNOTS AND INCREASING TO 100 KNOTS
WITHIN THE NEXT 12 HOURS.
EXPECT WINDS OVER 63 KNOTS WITHIN 30 NAUTICAL MILES OF CENTRE.
EXPECT WINDS OVER 47 KNOTS WITHIN 60 NAUTICAL MILES OF CENTRE IN
EASTERN SEMICIRCLE AND WITHIN 40 NAUTICAL MILES OF CENTRE ELSEWHERE.
EXPECT WINDS OVER 33 KNOTS WITHIN 200 NAUTICAL MILES OF CENTRE IN NE
QUADRANT
AND WITHIN 150 NAUTICAL MILES OF CENTRE IN SE QUADRANT
AND WITHIN 120 NAUTICAL MILES OF CENTRE IN SW QUADRANT
AND WITHIN 100 NAUTICAL MILES OF CENTRE IN NW QUADRANT.
STRUCTURE OF THE SYSTEM HAS WEAKEN IN LAST 3 HOURS BUT THE OVERALL
ORGANISATION REMAINS GOOD IN THE PAST 24 HOURS. EYE HAS BECOME CLOUD
FILLED IN PAST 3 HOURS. SLIGHT WARMING OF CLOUD TOPS PAST 3 HOURS.
PRIMARY BANDS TO SOUTH AND WEST OF SYSTEM CONSOLIDATING AND WRAPPING
AROUND LLCC. OUTFLOW GOOD TO SOUTH AND EAST BUT FAIR ESLEWHERE. SST
AROUND 29C. SYSTEM LIES ALONG IN A WEAK SHEAR ENVIRONMENT. CIMSS
INDICATES DECREASING SHEAR ALONG FORECAST PATH. SYSTEM IS BEING
STEERED SOUTHEAST BY A WEAK NORHTWESTERLY DEEP LAYER MEAN WIND.
DVORAK ASSESSMENT BASED ON EMBEDDE CENTRE PATTERN LG SURROUND
YIELDING DT = 5.0, MET 5.5 PT 5.0, FT BASED ON PT, THUS
T5.0/5.5/D1.5/24HRS.
GLOBAL MODELS CONTINUES TO INTENSIFY THE SYSTEM AND ARE MOVING IT
SOUTH-SOUTHEASTWARDS.
FORECASTS :
AT 12 HRS VALID AT 211200 UTC 19.1S 170.5E MOV SSE AT 07 KT WITH 100
KT CLOSE TO CENTRE
AT 24 HRS VALID AT 220000 UTC 20.9S 171.2E MOV SSE AT 10 KT WITH 100
KT CLOSE TO CENTRE
OUTLOOK :
AT 36 HRS VALID AT 221200 UTC 23.2S 172.1E MOV SSE AT 12 KT WITH 100
KT CLOSE TO CENTRE
AT 48 HRS VALID AT 230000 UTC 25.9S 173.7E MOV SSE AT 15 KT WITH 100
KT CLOSE TO CENTRE
You do not have the required permissions to view the files attached to this post.
TROPICAL DISTURBANCE ADVISORY NUMBER A14 ISSUED FROM RSMC NADI
Feb 21/0811 UTC 2011 UTC.
SEVERE TROPICAL CYCLONE ATU CENTRE 949HPA CAT 4 WAS LOCATED NEAR
18.3S 170.2E AT 210600 UTC. POSITION GOOD BASED ON MTSAT EIR/VIS
IMAGERY AND PERIPHERAL SURFACE OBSERVATIONS. CYCLONE MOVING SOUTHEAST
AT 05 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 90 KNOTS AND INCREASING TO 95 KNOTS WITHIN THE
NEXT 24 HOURS.
---
STRUCTURE OF THE SYSTEM HAS SLIGHTLY WEAKEN IN LAST 6 HOURS BUT THE
OVERALL ORGANISATION REMAINS GOOD IN THE PAST 24 HOURS. EYE HAS
SLIGHTLY EXPOSED. SLIGHT WARMING OF CLOUD TOPS PAST 6 HOURS. PRIMARY
BANDS TO SOUTH OF SYSTEM DISSIPATED WHILE THE BAND TO THE NORTH HAS
CONSOLIDATED AND WRAPPED AROUND LLCC. OUTFLOW GOOD TO NORTH AND EAST
BUT RESTRICTED ESLEWHERE. SST AROUND 29C. SYSTEM LIES ALONG IN A WEAK
SHEAR ENVIRONMENT. CIMSS INDICATES DECREASING SHEAR ALONG FORECAST
PATH. SYSTEM IS BEING STEERED SOUTHEAST BY A WEAK NORHTWESTERLY DEEP
LAYER MEAN WIND. DVORAK ASSESSMENT BASED ON EYE PATTERN WITH DG EYE
AND LG SURROUND YIELDING DT = 5.0, MET 5.0 PT 5.0, FT BASED ON DT,
THUS T5.0/5.5/D0.5/24HRS.
GLOBAL MODELS MOVING THE SYSTEM SOUTHEASTWARDS AND SLIGHT
INTENSIFICATION.
---
WTPS31 PGTW 210900
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 006//
---
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
---
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
SSMI AND 201716Z SSMI IMAGES) ALTHOUGH DEEP CONVECTION NEAR THE
CENTER HAS WEAKENED SLIGHTLY. INFRARED IMAGERY INDICATES WARMING
CLOUD TOPS, SUBSEQUENTLY, DVORAK ESTIMATES HAVE DECREASED AND THE
CURRENT INTENSITY IS NOW ASSESSED AS 100 KNOTS BASED ON AN AVERAGE
OF DVORAK FINAL-T AND CI ESTIMATES RANGING FROM 90 TO 115 KNOTS
FROM PGTW, KNES AND PHFO. TC 17P CONTINUES TO TRACK ALONG THE
WESTERN PERIPHERY OF THE MID-LEVEL STEERING RIDGE TO THE EAST
AND IS FORECAST TO ACCELERATE SOUTH-SOUTHEASTWARD TO SOUTHEASTWARD
WITHIN STRONG FLOW BETWEEN A DEEP MIDLATITUDE TROUGH AND THE
BUILDING STEERING RIDGE. MODEL GUIDANCE IS TIGHTLY-CLUSTERED AND
SUPPORTS THE CURRENT FORECAST. TC 17P IS EXPECTED TO BEGIN
EXTRA-TROPICAL TRANSITION (ETT) NEAR TAU 48 AS IT INTERACTS WITH
THE BAROCLINIC ZONE AND WILL COMPLETE ETT BY TAU 72 AS IT BECOMES
EMBEDDED WITHIN THE MIDLATITUDE TROUGH. TC 17P IS EXPECTED TO
INTENSIFY SLIGHTLY THROUGH TAU 24 BUT SHOULD WEAKEN RAPIDLY AFTER
TAU 36 DUE TO INCREASING VERTICAL WIND SHEAR AND COOLER SST. THE
SYSTEM SHOULD REMAIN A STRONG MIDLATITUDE LOW WITH 45-55 KNOT
WINDS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 210600Z IS 33 FEET. NEXT
WARNINGS AT 212100Z AND 220900Z.//
You do not have the required permissions to view the files attached to this post.
seems that it has started a more SE track already
it could still change to a SSE track for a while
but currently the future track has it missing NZ by a wider margin again
TROPICAL DISTURBANCE ADVISORY NUMBER A15 ISSUED FROM RSMC NADI
Feb 21/1357 UTC 2011 UTC.
SEVERE TROPICAL CYCLONE ATU CENTRE 940HPA CAT 4 WAS LOCATED NEAR
19.0S 170.5E AT 211200 UTC. POSITION GOOD BASED ON MTSAT IR IMAGERY
AND PERIPHERAL SURFACE OBSERVATIONS. CYCLONE MOVING SOUTH SOUTHEAST
AT 06 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 90 KNOTS.
EXPECT WINDS OVER 63 KNOTS WITHIN 30 NAUTICAL MILES OF CENTRE.
EXPECT WINDS OVER 47 KNOTS WITHIN 80 NAUTICAL MILES OF CENTRE IN THE
NE QUADRANT
AND WITHIN 130 NAUTICAL MILES OF CENTRE IN SE QUADRANT
AND WITHIN 80 NAUTICAL MILES OF CENTRE IN SW QUADRANT
AND WITHIN 40 NAUTICAL MILES OF CENTRE IN NW QUADRANT.
EXPECT WINDS OVER 33 KNOTS WITHIN 200 NAUTICAL MILES OF CENTRE IN NE
QUADRANT
AND WITHIN 160 NAUTICAL MILES OF CENTRE IN SE QUADRANT
AND WITHIN 100 NAUTICAL MILES OF CENTRE IN WESTERN SEMICIRCLE..
OVERALL ORGANISATION REMAINS GOOD. EYE PARTIALLY CLOUD FILLED BUT
STILL DISCERNIBLE. EYE WARMING AND CLOUD TOPS COOLING PAST 3 HOURS.
PRIMARY BANDS WRAPPING AROUND LLCC. OUTFLOW GOOD TO NORTH AND EAST
BUT FAIR ESLEWHERE. SST AROUND 29C. SYSTEM LIES ALONG A WEAK SHEARED
ENVIRONMENT. CIMSS INDICATES INCREASING SHEAR THAN DECREASING SHEAR
ALONG FORECAST PATH. SYSTEM IS BEING STEERED SOUTHEAST BY A
NORHTWESTERLY DEEP LAYER MEAN WIND. DVORAK ASSESSMENT BASED ON EYE
PATTERN WITH OW EYE AND LG SURROUND YIELDING DT = 5.0, MET 5.5 PT
5.0, FT BASED ON DT, THUS T5.0/5.5/S0.0/24HRS.
GLOBAL MODELS MOVE THE SYSTEM SOUTH SOUTHEAST.
FORECASTS :
AT 12 HRS VALID AT 220000 UTC 20.9.8S 171.3E MOV SSE AT 12 KT WITH 90
KT CLOSE TO CENTRE
AT 24 HRS VALID AT 221200 UTC 23.6S 172.6E MOV SSE AT 15 KT WITH 90
KT CLOSE TO CENTRE
OUTLOOK :
AT 36 HRS VALID AT 230000 UTC 26.7S 174.7E MOV SSE AT 17 KT WITH 90
KT CLOSE TO CENTRE
AT 48 HRS VALID AT 231200 UTC 30.1S 177.8E MOV SE AT 20 KT WITH 85 KT
CLOSE TO CENTRE
THE NEXT TROPICAL DISTURBANCE ADVISORY ON CYCLONE ATU WILL BE ISSUED
AROUND 212000 UTC.
You do not have the required permissions to view the files attached to this post.
amazing that its predicted to be still Cat 3 at the same latitude as North Cape as it does a fly by...
if it were to keep moving SSE and hit the NI,....as a Cat 3....
TROPICAL DISTURBANCE ADVISORY NUMBER A16 ISSUED FROM RSMC NADI
Feb 21/2001 UTC 2011 UTC.
SEVERE TROPICAL CYCLONE ATU CENTRE 940HPA CAT 4 WAS LOCATED NEAR
19.7S 171.0E AT 211800 UTC. POSITION GOOD BASED ON MTSAT IR IMAGERY
AND PERIPHERAL SURFACE OBSERVATIONS. CYCLONE MOVING SOUTH SOUTHEAST
AT 07 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 90 KNOTS.
---
OVERALL ORGANISATION REMAINS GOOD. EYE PARTIALLY CLOUD FILLED BUT
STILL DISCERNIBLE. EYE WARMING AND CLOUD TOPS COOLING PAST 3 HOURS.
PRIMARY BANDS WRAPPING AROUND LLCC. OUTFLOW GOOD TO NORTH AND EAST
BUT FAIR ESLEWHERE. SST AROUND 29C. SYSTEM LIES ALONG A WEAK SHEARED
ENVIRONMENT. CIMSS INDICATES INCREASING SHEAR ALONG FORECAST PATH.
SYSTEM IS BEING STEERED SOUTHEAST BY A NORHTWESTERLY DEEP LAYER MEAN
WIND. DVORAK ASSESSMENT BASED ON EYE PATTERN WITH OW EYE AND LG
SURROUND YIELDING DT=5.5,
MET=5.5, PT=5.0, FT BASED ON DT, THUS T5.5/5.5/S0.0/24HRS.
GLOBAL MODELS MOVE THE SYSTEM SOUTH SOUTHEAST .
---
WTPS31 PGTW 212100
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 17P (ATU) WARNING NR 007//
---
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
---
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.//
NNNN
You do not have the required permissions to view the files attached to this post.
