Yes, at this stage, Fiji's outlying southern islands and Tonga's northern islands appear to be at risk.
Winstone managed to retain Cat 3 status this morning (central pressure 972 hPa, max winds 120 km/h).
TROPICAL DISTURBANCE ADVISORY NUMBER A18 ISSUED FROM RSMC NADI
Feb 142021 UTC.
SEVERE TROPICAL CYCLONE WINSTON CENTRE 972HPA CATEGORY 3 WAS LOCATED
NEAR 24.1 SOUTH 178.7 EAST AT 141800 UTC. POSITION POOR BASED ON HR
MTSAT IR IMAGERY AND SURFACE OBSERVATIONS. CYCLONE MOVING
EAST-NORTHEAST AT ABOUT 13 KTS. MAXIMUM 10 MINUTE AVERAGE WINDS NEAR
THE CENTRE ESTIMATED AT ABOUT 65 KNOTS.
…
DEEP CONVECTION REMAINS PERSISTENT BUT DISPACED TO EAST OF LLCC.
ORGANIZATION REMAINS GOOD. SST AROUND 28 DEGREES CELSIUS. SYSTEM LIES
UNDER A MODERATE TO STRONG UPPER DIVERGENCE REGION AND IN A MODERATE
TO HIGH SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE EAST AND NORTH.
SYSTEM TRACKING ALONG THE SOUTHERN PERIPHERY OF THE SUB-TROPICAL
RIDGE LOCATED TO THE NORTH. DVORAK ANALYSIS BASED ON EMBEDDED CENTRE
PATTERN, LLCC EMBEDDED IN MG YIELDS DT=4.0, MET=4.0, PT=3.5. FT BASED
ON MET. CI HELD HIGHER DUE TO WEAKENING TREND. THUS YIELDING
T3.5/4.5/W1.5/24HRS.
FORECASTS :
AT 12 HRS VALID AT 150600 UTC 22.6S 179.6W MOV NE AT 11KT WITH 60KT
CLOSE TO CENTRE.
AT 24 HRS VALID AT 151800 UTC 21.2S 178.1W MOV NE AT 10KT WITH 55KT
CLOSE TO CENTRE.
OUTLOOK:
AT 36 HRS VALID AT 160600 UTC 19.9S 176.6W MOV NE AT 09KT WITH 60KT
CLOSE TO CENTRE.
AT 48 HRS VALID AT 161800 UTC 19.0S 175.1W MOV ENE AT 08KT WITH 60KT
CLOSE TO CENTRE.
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Winston was downgraded to Cat 2 earlier this arvo, and looking a little more dishevelled today.
Central pressure 975 hPa, max winds 110 km/h.
TROPICAL DISTURBANCE ADVISORY NUMBER A19 ISSUED FROM RSMC NADI
Feb 150134 UTC.
TROPICAL CYCLONE WINSTON CENTRE 975HPA CATEGORY 2 WAS LOCATED NEAR
22.7 SOUTH 179.8 EAST AT 150000 UTC. POSITION POOR BASED ON HR MTSAT
IR IMAGERY AND SURFACE OBSERVATIONS. CYCLONE MOVING EAST-NORTHEAST AT
ABOUT 13 KTS. MAXIMUM 10 MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 60 KNOTS.
…
DEEP CONVECTION REMAINS PERSISTENT BUT DISPLACED TO EAST OF LLCC.
ORGANIZATION REMAINS GOOD. SST AROUND 28 DEGREES CELSIUS. SYSTEM LIES
UNDER A MODERATE TO STRONG UPPER DIVERGENCE REGION AND IN A MODERATE
TO HIGH SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE EAST AND NORTH.
SYSTEM TRACKING ALONG THE SOUTHERN PERIPHERY OF THE SUB-TROPICAL
RIDGE LOCATED TO THE NORTH. DVORAK ANALYSIS BASED ON EMBEDDED CENTRE
PATTERN, LLCC EMBEDDED IN MG YIELDS DT=4.0, MET=3.5, PT=3.5. FT BASED
ON MET. CI HELD HIGHER DUE TO WEAKENING TREND. THUS YIELDING
T3.5/4.0/W1.0/24HRS.
FORECASTS :
AT 12 HRS VALID AT 151200 UTC 21.2S 178.4W MOV NE AT 11KT WITH 55KT
CLOSE TO CENTRE.
AT 24 HRS VALID AT 160000 UTC 19.7S 176.8W MOV NE AT 11KT WITH 55KT
CLOSE TO CENTRE.
OUTLOOK:
AT 36 HRS VALID AT 161200 UTC 18.7S 175.0W MOV ENE AT 10KT WITH 60KT
CLOSE TO CENTRE.
AT 48 HRS VALID AT 170000 UTC 18.1S 173.5W MOV ENE AT 08KT WITH 65KT
CLOSE TO CENTRE.
WTPS31 PGTW 150300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 11P (WINSTON) WARNING NR 010//
RMKS/
1. TROPICAL CYCLONE 11P (WINSTON) 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:
150000Z --- NEAR 23.0S 179.6E
MOVEMENT PAST SIX HOURS - 035 DEGREES AT 13 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
…
REMARKS:
150300Z POSITION NEAR 22.6S 179.9E.
TROPICAL CYCLONE 11P (WINSTON), LOCATED APPROXIMATELY 302 NM
SOUTH-SOUTHEAST OF SUVA, FIJI, HAS TRACKED NORTHEASTWARD AT 13
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS THAT TC 11P HAS MAINTAINED TIGHTLY CURVED SPIRAL
BANDING WRAPPING INTO A LOW LEVEL CIRCULATION CENTER (LLCC)
WHILE DEEP CONVECTION HAS SHALLOWED SLIGHTLY. THE INITIAL POSITION
IS BASED UPON AGENCY FIXES AND A 142044Z PARTIAL ASCAT PASS WITH
GOOD CONFIDENCE. THE INITIAL INTENSITY IS ASSESSED AT 60 KNOTS BASED
UPON THE SCATTEROMETRY DATA WHICH HAD A SWATH OF 65 KNOT WINDS ALONG
THE SOUTHERN SEMI-CIRCLE, AND TAKING INTO ACCOUNT MORE RECENT AGENCY
DVORAK CURRENT INTENSITY ESTIMATES OF 55 KNOTS. ENVIRONMENTAL
CONDITIONS REMAIN MARGINAL AS TC 11P REMAINS EMBEDDED WITHIN A
TROUGH WITH MODERATE TO STRONG VERTICAL WIND SHEAR (VWS), HOWEVER
THE EASTWARD OUTFLOW CHANNEL REMAINS ROBUST AND SSTS ARE GRADUALLY
RISING AS THE SYSTEM TRACKS EQUATORWARD. WINSTON IS FORECAST TO
CONTINUE TRACKING GENERALLY NORTHEASTWARD OVER THE NEXT TWO DAYS AS
RIDGING BUILDS IN BEHIND THE SYSTEM AND PROVIDES A WEAK STEERING
FLOW. BY DAY TWO, TC 11P WILL SLOW AS MUCH MORE PRONOUNCED SUB-
TROPICAL RIDGING FORMS AHEAD OF IT, RESULTING IN A SLOW TURN OR LOOP
BACK TO THE WEST STARTING AROUND DAY THREE. WINSTON IS FORECAST TO
WEAKEN SLIGHTLY OVER THE NEXT 24 HOURS AS IT CONTINUES TO TRACK
THROUGH AN ENVIRONMENT WITH STRONG VWS. AS THE CURRENT UPPER LEVEL
TROUGHING MOVES OFF, GRADUAL RE-INTENSIFICATION OF THE SYSTEM IS
FORECAST AS IT TRACKS OVER AN AREA WITH LOWER VWS AND WARMER SSTS.
THIS INTENSIFICATION MAY BECOME MORE PRONOUNCED AS THE FOREWARD
MOTION STALLS DURING THE TURN. DYNAMIC MODEL GUIDANCE IS IN POOR
AGREEMENT ON THE SYNOPTIC STEERING PATTERN WITH SIGNIFICANT
DIFFERENCES. THEREFORE, THERE IS LOW CONFIDENCE IN THE JTWC FORECAST
TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 150000Z IS 21 FEET. NEXT
WARNINGS AT 151500Z AND 160300Z.
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Central pressure up to 980 hPa and max winds down to 100 km/h. Convection displaced to east of LLCC. Winston's taken a bit of a battering today, but shear should start to ease after tomorrow and warmer SST's of around 29/30C will give Winston a chance to regroup...
TROPICAL DISTURBANCE ADVISORY NUMBER A20 ISSUED FROM RSMC NADI
Feb 150755 UTC.
TROPICAL CYCLONE WINSTON CENTRE 980HPA CATEGORY 2 WAS LOCATED NEAR
21.8 SOUTH 179.5 WEST AT 150600 UTC. POSITION FAIR BASED ON HR MTSAT
IR IMAGERY AND SURFACE OBSERVATIONS. CYCLONE MOVING NORTHEAST AT
ABOUT 11 KTS. MAXIMUM 10 MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 55 KNOTS.
…
DEEP CONVECTION REMAINS PERSISTENT BUT ABOUT EAST OF LLCC.
ORGANIZATION REMAINS GOOD. SST AROUND 28 TO 29 DEGREES CELSIUS.
SYSTEM LIES UNDER A MODERATE UPPER DIVERGENCE REGION AND IN A HIGH
SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE EAST. SYSTEM TRACKING
NORTHEAST DUE TO THE SUB-TROPICAL RIDGE LOCATED TO THE NORTH. DVORAK
ANALYSIS BASED ON 0.6 WRAP YIELDS DT=3.0, MET AND PT AGREE. FT BASED
ON DT. CI HELD HIGHER DUE TO WEAKENING TREND. THUS YIELDING
T3.0/3.5/W1.0/24HRS.
FORECASTS :
AT 12 HRS VALID AT 151800 UTC 20.3S 178.1W MOV NE AT 10KT WITH 55KT
CLOSE TO CENTRE.
AT 24 HRS VALID AT 160600 UTC 19.1S 176.8W MOV NE AT 10KT WITH 55KT
CLOSE TO CENTRE.
OUTLOOK:
AT 36 HRS VALID AT 161800 UTC 18.2S 175.5W MOV ENE AT 8KT WITH 60KT
CLOSE TO CENTRE.
AT 48 HRS VALID AT 170600 UTC 17.6S 174.5W MOV ENE AT 08KT WITH 60KT
CLOSE TO CENTRE.
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Winston weakened a little more than forecast last night and earlier this morning was barely a low-end Cat 2. Convection displaced to the east was more shallow last night, but this morning has deepened considerably. Central pressure was 985 hPa, with max winds around 93 km/h…
TROPICAL DISTURBANCE ADVISORY NUMBER A21 ISSUED FROM RSMC NADI
Feb 151351 UTC.
TROPICAL CYCLONE WINSTON CENTRE 985HPA CATEGORY 2 WAS LOCATED NEAR
20.6 SOUTH 178.1 WEST AT 151200 UTC. POSITION FAIR BASED ON HR MTSAT
IR IMAGERY AND SURFACE OBSERVATIONS. CYCLONE MOVING NORTHEAST AT
ABOUT 18 KTS. MAXIMUM 10 MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 50 KNOTS.
…
DEEP CONVECTION REMAINS PERSISTENT BUT DISPLACED JUST EAST OF LLCC.
ORGANIZATION REMAINS GOOD. SST AROUND 28 TO 29 DEGREES CELSIUS.
SYSTEM LIES UNDER A MODERATE UPPER DIVERGENCE REGION AND IN A
MODERATE TO HIGH SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE EAST.
SYSTEM IS BEING STEERED TO THE NORTHEAST BY THE SOUTHWEST DEEP LAYER
MEAN WIND FLOW. DVORAK ANALYSIS BASED ON 0.4 WRAP YIELDS DT=2.5, MET
AND PT AGREE. FT BASED ON DT. CI HELD HIGHER DUE TO WEAKENING TREND.
THUS YIELDING T2.5/3.5/W1.0/24HRS.
FORECASTS :
AT 12 HRS VALID AT 160000 UTC 19.3S 176.7W MOV NE AT 09KT WITH 55KT
CLOSE TO CENTRE.
AT 24 HRS VALID AT 161200 UTC 18.4S 175.7W MOV NE AT 08KT WITH 55KT
CLOSE TO CENTRE.
OUTLOOK:
AT 36 HRS VALID AT 170000 UTC 17.5S 174.7W MOV NE AT 07KT WITH 55KT
CLOSE TO CENTRE.
AT 48 HRS VALID AT 171200 UTC 16.7S 174.0W MOV NE AT 06KT WITH 55KT
CLOSE TO CENTRE.
WTPS31 PGTW 151500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 11P (WINSTON) WARNING NR 011//
RMKS/
1. TROPICAL CYCLONE 11P (WINSTON) 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:
151200Z --- NEAR 20.6S 178.1W
MOVEMENT PAST SIX HOURS - 050 DEGREES AT 18 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
…
REMARKS:
151500Z POSITION NEAR 20.3S 177.7W.
TROPICAL CYCLONE 11P (WINSTON), LOCATED APPROXIMATELY 248 NM
SOUTHEAST OF SUVA, FIJI, HAS TRACKED NORTHEASTWARD AT 18 KNOTS OVER
THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY
REVEALS TC 11P REMAINS EMBEDDED WITHIN THE TROUGH, HOWEVER DEEP
CONVECTIVE COVERAGE HAS BEGUN TO EXPAND AND CLOUD-TOPS HAVE COOLED
OVER THE PAST 6 HOURS. A 151051Z GPM 36 GHZ IMAGE DEPICTS A WELL-
DEFINED LOW-LEVEL CIRCULATION CENTER (LLCC) WITH TIGHTLY CURVED
BANDING WRAPPING INTO THE SYSTEM. THE INITIAL POSITION IS BASED UPON
A 150958Z ASCAT AMBIGUITY ANALYSIS WITH GOOD CONFIDENCE. THE INITIAL
INTENSITY IS ASSESSED AT 50 KNOTS BASED UPON THE RECENT
SCATTEROMETRY DATA. UPPER LEVEL ANALYSIS SHOWS A MARGINALLY-
FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH GOOD OUTFLOW OFFSET BY
MODERATE TO STRONG (20 TO 30 KNOTS) VERTICAL WIND SHEAR (VWS). TC
WINSTON IS FORECAST TO CONTINUE TRACKING NORTHEASTWARD ALONG THE
SOUTHEAST PERIPHERY OF THE STEERING RIDGE. A WEAKNESS IN THE RIDGE
IS FORECAST TO FORM BETWEEN TAU 36 THROUGH TAU 72, CAUSING THE
SYSTEM TO SLOW IN FORWARD SPEED, AND THEN BECOME QUASI-STATIONARY
AFTER TAU 36, AS A SECONDARY RIDGE BUILDS IN FROM THE SOUTHWEST.
AFTER TAU 72, TC 11P WILL BEGIN TO ACCELERATE WESTWARD AS THE RIDGE
TO THE EAST STRENGTHENS AND THE RIDGE TO THE SOUTHWEST MOVES
WESTWARD. TC WINSTON IS FORECAST TO GRADUALLY RE-INTENSIFY DURING
THE FORECAST PERIOD AS IT TRACKS OVER WARMER (29-30C) SSTS AND
THROUGH A REGION OF DECREASING VWS. DYNAMIC MODEL GUIDANCE IS IN
FAIR AGREEMENT THROUGH TAU 48, HOWEVER, SOLUTIONS BEGIN TO DIVERGE
AFTER TAU 48 DUE TO HIGH UNCERTAINTY WITH THE OVERALL SYNOPTIC
STEERING PATTERN. THEREFORE, THERE IS LOW CONFIDENCE IN THE JTWC
FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 151200Z IS 21
FEET. NEXT WARNINGS AT 160300Z AND 161500Z.//
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Winston has settled down a bit now after a spectacular diurnal burst of deep convection in the 6 hours from about midnight. Nadi also had him bottoming at 987 hPa at 7am this morning (currently 985 hPa). Max winds remain around 93 km/h. Shear is starting to ease and SST's are round 30C. JTWC expect he'll be back up to Cat 3 on Thursday. Contrary to their previous forecast, they now also expect a slow turn to the SE by Saturday…
TROPICAL DISTURBANCE ADVISORY NUMBER A23 ISSUED FROM RSMC NADI
Feb 160202 UTC.
TROPICAL CYCLONE WINSTON CENTRE 985HPA CATEGORY 2 WAS LOCATED NEAR
19.1 SOUTH 175.6 WEST AT 160000 UTC. POSITION FAIR BASED ON HR MTSAT
IR/VIS IMAGERY AND SURFACE OBSERVATIONS. CYCLONE MOVING NORTHEAST AT
ABOUT 14 KTS. MAXIMUM 10 MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 50 KNOTS.
…
DEEP CONVECTION REMAINS PERSISTENT WITH RAIN BANDS WRAPPING AROUND
SUPPSED LLCC PAST 6 HOURS. ORGANIZATION REMAINS GOOD. SST AROUND 28
TO 29 DEGREES CELSIUS. SYSTEM LIES UNDER A MODERATE UPPER DIVERGENCE
REGION AND IN MODERATE SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE EAST.
SYSTEM IS BEING STEERED TO THE NORTHEAST BY THE SOUTHWEST DEEP LAYER
MEAN WIND FLOW. DVORAK ANALYSIS BASED ON 0.75 WRAP YIELDS DT=3.0, MET
AND PT AGREE. FT BASED ON DT. THUS YIELDING T3.0/3.5/W0.5/24HRS.
FORECASTS :
AT 12 HRS VALID AT 161200 UTC 18.2S 174.3W MOV NE AT 08KT WITH 55KT
CLOSE TO CENTRE.
AT 24 HRS VALID AT 170000 UTC 17.5S 173.2W MOV ENE AT 06KT WITH 60KT
CLOSE TO CENTRE.
OUTLOOK:
AT 36 HRS VALID AT 171200 UTC 16.9S 172.4W MOV NE AT 05KT WITH 60KT
CLOSE TO CENTRE.
AT 48 HRS VALID AT 180000 UTC 16.5S 172.2W MOV NE AT 02KT WITH 60KT
CLOSE TO CENTRE.
WTPS31 PGTW 151500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 11P (WINSTON) WARNING NR 011//
RMKS/
1. TROPICAL CYCLONE 11P (WINSTON) 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:
151200Z --- NEAR 20.6S 178.1W
MOVEMENT PAST SIX HOURS - 050 DEGREES AT 18 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
…
REMARKS:
151500Z POSITION NEAR 20.3S 177.7W.
TROPICAL CYCLONE 11P (WINSTON), LOCATED APPROXIMATELY 248 NM
SOUTHEAST OF SUVA, FIJI, HAS TRACKED NORTHEASTWARD AT 18 KNOTS OVER
THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY
REVEALS TC 11P REMAINS EMBEDDED WITHIN THE TROUGH, HOWEVER DEEP
CONVECTIVE COVERAGE HAS BEGUN TO EXPAND AND CLOUD-TOPS HAVE COOLED
OVER THE PAST 6 HOURS. A 151051Z GPM 36 GHZ IMAGE DEPICTS A WELL-
DEFINED LOW-LEVEL CIRCULATION CENTER (LLCC) WITH TIGHTLY CURVED
BANDING WRAPPING INTO THE SYSTEM. THE INITIAL POSITION IS BASED UPON
A 150958Z ASCAT AMBIGUITY ANALYSIS WITH GOOD CONFIDENCE. THE INITIAL
INTENSITY IS ASSESSED AT 50 KNOTS BASED UPON THE RECENT
SCATTEROMETRY DATA. UPPER LEVEL ANALYSIS SHOWS A MARGINALLY-
FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH GOOD OUTFLOW OFFSET BY
MODERATE TO STRONG (20 TO 30 KNOTS) VERTICAL WIND SHEAR (VWS). TC
WINSTON IS FORECAST TO CONTINUE TRACKING NORTHEASTWARD ALONG THE
SOUTHEAST PERIPHERY OF THE STEERING RIDGE. A WEAKNESS IN THE RIDGE
IS FORECAST TO FORM BETWEEN TAU 36 THROUGH TAU 72, CAUSING THE
SYSTEM TO SLOW IN FORWARD SPEED, AND THEN BECOME QUASI-STATIONARY
AFTER TAU 36, AS A SECONDARY RIDGE BUILDS IN FROM THE SOUTHWEST.
AFTER TAU 72, TC 11P WILL BEGIN TO ACCELERATE WESTWARD AS THE RIDGE
TO THE EAST STRENGTHENS AND THE RIDGE TO THE SOUTHWEST MOVES
WESTWARD. TC WINSTON IS FORECAST TO GRADUALLY RE-INTENSIFY DURING
THE FORECAST PERIOD AS IT TRACKS OVER WARMER (29-30C) SSTS AND
THROUGH A REGION OF DECREASING VWS. DYNAMIC MODEL GUIDANCE IS IN
FAIR AGREEMENT THROUGH TAU 48, HOWEVER, SOLUTIONS BEGIN TO DIVERGE
AFTER TAU 48 DUE TO HIGH UNCERTAINTY WITH THE OVERALL SYNOPTIC
STEERING PATTERN. THEREFORE, THERE IS LOW CONFIDENCE IN THE JTWC
FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 151200Z IS 21
FEET. NEXT WARNINGS AT 160300Z AND 161500Z.//
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Another good burst of deep convection from around 4pm today. Status unchanged. Nadi's track-map also reflects a flip in Winston's u-turn on Thursday since their previous track-map.
TROPICAL DISTURBANCE ADVISORY NUMBER A24 ISSUED FROM RSMC NADI
Feb 160736 UTC.
TROPICAL CYCLONE WINSTON CENTRE 985HPA CATEGORY 2 WAS LOCATED NEAR
18.8 SOUTH 174.8 WEST AT 160600 UTC. POSITION FAIR BASED ON HR MTSAT
IR IMAGERY AND SURFACE OBSERVATIONS. CYCLONE MOVING NORTHEAST AT
ABOUT 14 KTS. MAXIMUM 10 MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 50 KNOTS.
…
DEEP CONVECTION REMAINS PERSISTENT WITH CONVECTIVE BAND WRAPPING
TIGHTLY AROUND LLCC. ORGANIZATION REMAINS GOOD. SST AROUND 30 DEGREES
CELSIUS. SYSTEM LIES UNDER A MODERATE UPPER DIVERGENCE REGION AND IN
MODERATE SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE EAST. SYSTEM IS
BEING STEERED TO THE NORTHEAST BY THE SOUTHWEST DEEP LAYER MEAN WIND
FLOW. DVORAK ANALYSIS BASED ON 0.8 WRAP YIELDS DT=3.5, MET AND PT
AGREE. FT BASED ON DT. THUS YIELDING T3.5/3.5/D0.5/24HRS.
FORECASTS :
AT 12 HRS VALID AT 161800 UTC 18.0S 173.1W MOV ENE AT 09KT WITH 55KT
CLOSE TO CENTRE.
AT 24 HRS VALID AT 170600 UTC 17.5S 171.7W MOV ENE AT 08KT WITH 55KT
CLOSE TO CENTRE.
OUTLOOK:
AT 36 HRS VALID AT 171800 UTC 17.4S 170.8W MOV E AT 05KT WITH 60KT
CLOSE TO CENTRE.
AT 48 HRS VALID AT 180600 UTC 17.5S 170.7W MOV E AT 02KT WITH 60KT
CLOSE TO CENTRE.
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Winston regained strength last night and earlier this morning central pressure was down to 975 hPa, with max winds up to 110 km/h.
TROPICAL DISTURBANCE ADVISORY NUMBER A25 ISSUED FROM RSMC NADI
Feb 161354 UTC.
TROPICAL CYCLONE WINSTON CENTRE 975HPA CATEGORY 2 WAS LOCATED NEAR
18.0 SOUTH 173.7 WEST AT 161200 UTC. POSITION FAIR BASED ON HR MTSAT
IR IMAGERY AND SURFACE OBSERVATIONS. CYCLONE MOVING EAST-NORTHEAST AT
ABOUT 12 KTS. MAXIMUM 10 MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 60 KNOTS.
…
DEEP CONVECTION REMAINS PERSISTENT WITH CONVECTIVE BAND WRAPPING
AROUND LLCC. ORGANIZATION REMAINS GOOD. SST AROUND 30 DEGREES
CELSIUS. SYSTEM LIES UNDER A MODERATE UPPER DIVERGENCE REGION AND IN
LOW TO MODERATE SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE EAST. SYSTEM
IS BEING STEERED TO THE EAST-NORTHEAST BY THE WEST-SOUTHWEST DEEP
LAYER MEAN WIND FLOW. DVORAK ANALYSIS BASED ON 1.0 WRAP WITH WHITE
BAND YIELDS DT=4.0, MET AND PT AGREE. FT BASED ON DT. THUS YIELDING
T4.0/4.0/D1.5/24HRS.
FORECASTS :
AT 12 HRS VALID AT 170000 UTC 17.5S 172.0W MOV ENE AT 08KT WITH 65KT
CLOSE TO CENTRE.
AT 24 HRS VALID AT 171200 UTC 17.3S 170.9W MOV ENE AT 06KT WITH 70KT
CLOSE TO CENTRE.
OUTLOOK:
AT 36 HRS VALID AT 180000 UTC 17.2S 170.4W MOV E AT 03KT WITH 75KT
CLOSE TO CENTRE.
AT 48 HRS VALID AT 181200 UTC 17.4S 170.7W MOV SE AT 02KT WITH 80KT
CLOSE TO CENTRE.
WTPS31 PGTW 161500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL CYCLONE 11P (WINSTON) WARNING NR 014
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
161200Z --- NEAR 17.9S 173.6W
MOVEMENT PAST SIX HOURS - 055 DEGREES AT 10 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
…
REMARKS:
161500Z POSITION NEAR 17.8S 173.2W.
TROPICAL CYCLONE (TC) 11P (WINSTON), LOCATED APPROXIMATELY 273 NM
SOUTHWEST OF PAGO PAGO, HAS TRACKED NORTHEASTWARD AT 10 KNOTS
OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS CONVECTIVE BANDING WRAPPING INTO AN AREA OF
INCREASED CENTRAL CONVECTION WITH A WEAKLY DEFINED 23NM EYE, GIVING
VERY HIGH CONFIDENCE TO THE INITIAL POSITION. A 160937Z SSMIS 89 GHZ
MICROWAVE IMAGE ALSO SHOWS INCREASED CENTRAL CONVECTION SURROUNDING
THE MICROWAVE EYE. THE INITIAL INTENSITY IS 65 KNOTS AND BASED ON
DVORAK ESTIMATES FROM PGTW REPORTING T4.0 (65 KNOTS). TC WINSTON IS
CURRENTLY POSITIONED IN A GOOD ENVIRONMENT FOR INTENSIFICATION WITH
FAVORABLE SEA SURFACE TEMPERATURES (30 CELSIUS) AND LOW (10 TO 15
KNOTS) VERTICAL WIND SHEAR. A STRONG WESTERLY OUTFLOW CHANNEL IS
ALSO SUPPORTING THE CURRENT INTENSIFICATION, TAPPING INTO A LONGWAVE
TROUGH POSITIONED TO THE SOUTHEAST. A SUBTROPICAL RIDGE TO THE
NORTHWEST IS STEERING THE CYCLONE ALONG AN EASTWARD TRACK. DYNAMIC
MODEL GUIDANCE SUGGESTS THAT BY TAU 24 THE RIDGE WILL WEAKEN
SIGNIFICANTLY PROVIDING A VERY WEAK STEERING ENVIRONMENT, AND
TC WINSTON IS EXPECTED TO BECOME QUASI-STATIONARY AND REMAIN IN A
WEAK STEERING ENVIRONMENT UNTIL APPROXIMATELY TAU 96 WHEN AN EAST-
WEST RIDGE BEGINS TO BUILD TO THE SOUTH SENDING TC WINSTON ON A
WESTWARD TRACK. ENVIRONMENTAL CONDITIONS WILL REMAIN FAVORABLE WHICH
WILL SUPPORT INTENSIFICATION, AND TC WINSTON IS EXPECTED TO REACH
100 KNOTS BY TAU 48. DUE TO THE WEAK AND COMPETING STEERING
ENVIRONMENT, MODEL GUIDANCE IS IN DISAGREEMENT AS THE CYCLONE
BECOMES QUASI-STATIONARY; HOWEVER HAS IMPROVED WITH THE EXTENDED
FORECAST TURN TO THE WEST. THIS PROVIDES LOW CONFIDENCE TO THE JTWC
FORECAST TRACK BEYOND TAU 24. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
161200Z IS 24 FEET. NEXT WARNINGS AT 162100Z, 170300Z, 170900Z AND
171500Z.//
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TC Winston upgraded back up to Cat 3 this morning - central pressure 970, max winds 120 km/h…
TROPICAL DISTURBANCE ADVISORY NUMBER A26 ISSUED FROM RSMC NADI
Feb 161949 UTC.
SEVERE TROPICAL CYCLONE WINSTON CENTRE 970HPA CATEGORY 3 WAS LOCATED
NEAR 17.5 SOUTH 172.8 WEST AT 161800 UTC. POSITION POOR BASED ON HR
MTSAT IR IMAGERY AND SURFACE OBSERVATIONS. CYCLONE MOVING
EAST-NORTHEAST AT ABOUT 12 KTS. MAXIMUM 10 MINUTE AVERAGE WINDS NEAR
THE CENTRE ESTIMATED AT ABOUT 65 KNOTS.
…
DEEP CONVECTION REMAINS PERSISTENT PAST 24 HOURS. ORGANIZATION
REMAINS GOOD. SST AROUND 30 DEGREES CELSIUS. SYSTEM LIES UNDER A
MODERATE UPPER DIVERGENCE REGION AND IN MODERATE SHEARED ENVIRONMENT.
OUTFLOW GOOD TO THE EAST. SYSTEM IS BEING STEERED TO THE
EAST-NORTHEAST BY THE WEST-SOUTHWEST DEEP LAYER MEAN WIND FLOW.
DVORAK ANALYSIS BASED ON CENTRE EMBEDDED IN WHITE YIELDS DT=5.0,
MET=4.5, PT=4.5. FT BASED ON MET. THUS YIELDING T4.5/4.5/D1.5/24HRS.
FORECASTS :
AT 12 HRS VALID AT 170600 UTC 17.2S 171.4W MOV ENE AT 07KT WITH 70KT
CLOSE TO CENTRE.
AT 24 HRS VALID AT 171800 UTC 17.3S 170.6W MOV E AT 04KT WITH 70KT
CLOSE TO CENTRE.
OUTLOOK:
AT 36 HRS VALID AT 180600 UTC 17.2S 170.6W MOV S AT 02KT WITH 75KT
CLOSE TO CENTRE.
AT 48 HRS VALID AT 181800 UTC 17.4S 171.4W MOV WSW AT 04KT WITH 80KT
CLOSE TO CENTRE.
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Winston has developed a ragged but discernable eye this afternoon. Central pressure 968 hPa, max winds to 130 km/h this afternoon. JTWC going for a high-end Cat 5 tomorrow…
TROPICAL DISTURBANCE ADVISORY NUMBER A27 ISSUED FROM RSMC NADI
Feb 170136 UTC.
SEVERE TROPICAL CYCLONE WINSTON CENTRE 968HPA CATEGORY 3 WAS LOCATED
NEAR 17.7 SOUTH 171.6 WEST AT 170000 UTC. POSITION FAIR BASED ON HR
MTSAT IR/VIS IMAGERY AND SURFACE OBSERVATIONS. CYCLONE MOVING EAST AT
ABOUT 10 KTS. MAXIMUM 10 MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 70 KNOTS.
…
DEEP CONVECTION REMAINS PERSISTENT WITH RAGGED EYE DISCERNIBLE ON VIS
IMAGERY PAST 3 HOURS. ORGANIZATION REMAINS GOOD. SST AROUND 30
DEGREES CELSIUS. SYSTEM LIES UNDER A MODERATE UPPER DIVERGENCE REGION
AND IN MODERATE SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE EAST. SYSTEM
IS BEING STEERED TO THE EAST BY THE WEST-SOUTHWEST DEEP LAYER MEAN
WIND FLOW. DVORAK ANALYSIS BASED ON W EYE IN B SURROUND, ADJUSTMENT
MADE DUE TO W EYE EMBEDDED IN W WITH BANDING YIELDS DT=5.0, MET=4.5,
PT=4.5. FT BASED ON MET. THUS YIELDING T4.5/4.5/D1.5/24HRS.
FORECASTS :
AT 12 HRS VALID AT 171200 UTC 17.6S 170.4W MOV E AT 06KT WITH 80KT
CLOSE TO CENTRE.
AT 24 HRS VALID AT 180000 UTC 17.7S 169.9W MOV E AT 02KT WITH 85KT
CLOSE TO CENTRE.
OUTLOOK:
AT 36 HRS VALID AT 181200 UTC 17.9S 170.4W MOV WSW AT 02KT WITH 90KT
CLOSE TO CENTRE.
AT 48 HRS VALID AT 190000 UTC 18.2S 171.5W MOV WSW AT 06KT WITH 90KT
CLOSE TO CENTRE.
WTPS31 PGTW 170300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL CYCLONE 11P (WINSTON) WARNING NR 016
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
170000Z --- NEAR 17.5S 171.8W
MOVEMENT PAST SIX HOURS - 090 DEGREES AT 06 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
…
REMARKS:
170300Z POSITION NEAR 17.5S 171.5W.
TROPICAL CYCLONE 11P (WINSTON), LOCATED APPROXIMATELY 145 NM
NORTHWEST OF NIUE, HAS TRACKED EASTWARD AT 06 KNOTS OVER THE PAST
SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS DEEP
CONVECTION CONTINUING TO IMPROVE WITH COLD CONVECTIVE TOPS WRAPPING
INTO A VERY COMPACT EYE THAT HAS DEVELOPED OVER THE PAST TWO HOURS.
A 162321Z GPM 91 GHZ MICROWAVE PASS INDICATES THAT DEEP CONVECTION
COMPLETELY SURROUNDS A DISTINCT AND COMPACT MICROWAVE EYE FEATURE,
LEADING TO HIGH CONFIDENCE IN THE INITIAL POSITION. THE INITIAL
INTENSITY IS ASSESSED AT 90 KNOTS BASED ON DVORAK ESTIMATES OF T5.0
FROM ALL AGENCIES. ANALYSIS INDICATES THAT THE OVERALL ENVIRONMENT
SURROUNDING TC WINSTON REMAINS FAVORABLE. VERTICAL WIND SHEAR (VWS)
VALUES HAVE DECREASED OVER THE PAST SIX HOURS AND ARE NOW IN THE LOW
RANGE (10 TO 15 KNOTS). SEA SURFACE TEMPERATURE REMAINS HIGH (30
CELSIUS) AND THERE ARE INDICATIONS OF THE DEVELOPMENT OF AN
EQUATORWARD OUTFLOW CHANNEL IN ADDITION TO THE ESTABLISHED EASTWARD
CHANNEL. THE PRIMARY STEERING MECHANISM REMAINS THE DEEP-LAYER NEAR-
EQUATORIAL RIDGE TO THE NORTH, WHICH WILL CONTINUE TO STEER TC
WINSTON ON ITS CURRENT EASTWARD TRACK FOR THE NEXT 12 HOURS, ALBEIT
AT A MUCH SLOWER PACE, TC WINSTON HAVING ALREADY SLOWED
SIGNIFICANTLY SINCE THE PREVIOUS WARNING. AS A RIDGE BUILDS TO THE
SOUTH OF THE TC, A DEEP-LAYER SUBTROPICAL RIDGE (STR) WILL
SIMULTANEOUSLY BUILD IN FROM THE EAST, CAUSING TC WINSTON TO BECOME
QUASI-STATIONARY BY TAU 24. AFTER TAU 36, UNDER THE COMBINED
INFLUENCE OF THE TWO AFOREMENTIONED RIDGES, TC WINSTON WILL
TRANSLATE TO A WEST-SOUTHWESTWARD TRACK AND ACCELERATE THROUGH TAU
72. THROUGH THE REMAINING PORTION OF THE FORECAST PERIOD, TC WINSTON
WILL TRANSITION TO A MORE SOUTHWARD TRACK TOWARDS A WEAKNESS IN THE
STR AHEAD OF AN ADVANCING MID-LATITUDE TROUGH. ENVIRONMENTAL
CONDITIONS ARE FAVORABLE FOR A PERIOD OF RAPID INTENSIFICATION OVER
THE NEXT 24 HOURS, PEAK INTENSITY REACHING 125 KNOTS BY TAU 36.
THEREAFTER THE SYNOPTIC ENVIRONMENT REMAINS SUPPORTIVE OF
MAINTAINING TC WINSTON AS AN INTENSE SYSTEM THROUGH THE END OF THE
FORECAST PERIOD. DYNAMIC MODEL GUIDANCE HAS COME INTO BETTER
AGREEMENT BUT STILL DEPICTS MODERATE UNCERTAINTY AFTER TAU 48. DUE
TO THIS UNCERTAINTY, THERE IS LOW CONFIDENCE TO THE JTWC FORECAST
TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 170000Z IS 32 FEET. NEXT
WARNINGS AT 170900Z, 171500Z, 172100Z AND 180300Z.//
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At this stage Tonga's main islands may be ok if Winston back-tracks over the same path already taken. Also not sure whether he will reach Cat 5 as forecast by JTWC, as that path will take him over the same waters that presumably he would have just cooled a little.
Winston's central pressure earlier this morning was 960 hPa, with max-winds of 150 km/h. Intensification has slowed recently due to the entrainment of a thin band of dry air. However, Winston is still expected to reach Cat 4 later this morning. Wind shear has eased considerably and SST's are currently around 30C...
TROPICAL DISTURBANCE ADVISORY NUMBER A29 ISSUED FROM RSMC NADI
Feb 171350 UTC.
SEVERE TROPICAL CYCLONE WINSTON CENTRE 960HPA WAS LOCATED NEAR 17.1S
170.9W AT 171200 UTC. POSITION FAIRR BASED ON HR GOES EIR AND
PERIPHERAL SURFACE REPORTS. CYCLONE MOVING EAST-NORTHEAST AT ABOUT
07 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE ESTIMATED
AT ABOUT 80 KNOTS.
..
DEEP CONVECTION REMAINS PERSISTENT.ORGANIZATION REMAINS GOOD. SST
AROUND 29-30 DEGREES CELSIUS. SYSTEM LIES UNDER A MODERATE UPPER
DIVERGENCE REGION IN LOW TO MODERATE SHEARED ENVIRONMENT. OUTFLOW
GOOD TO THE EAST. DVORAK ANALYSIS BASED ON EMBEDDED CENTRE PATTERN
WITH LLCC EMBEDDED IN W YEILDS DT=5.0, MET=5.0, PT=4.5.
FT BASED ON MET. THUS YIELDING T5.0/5.0/D1.0/24HRS.
FORECASTS :
AT 12 HRS VALID AT 180000 UTC 17.1S 170.7W SLOW MOV WITH 90KT CLOSE
TO CENTRE
AT 24 HRS VALID AT 181200 UTC 17.3S 171.4W MOV WSW AT 03KT WITH 95 KT
CLOSE TO CENTRE
OUTLOOK :
AT 36 HRS VALID AT 190000 UTC 17.6S 172.6W MOV WSW AT 06KT WITH 100
KT CLOSE TO CENTRE
AT 48 HRS VALID AT 191200 UTC 18.0S 174.1W MOV WSW AT 07KT WITH 100
KT CLOSE TO CENTRE
SWTPS31 PGTW 170900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL CYCLONE 11P (WINSTON) WARNING NR 017
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
170600Z --- NEAR 17.5S 171.2W
MOVEMENT PAST SIX HOURS - 090 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
…
REMARKS:
170900Z POSITION NEAR 17.5S 171.1W.
TROPICAL CYCLONE (TC) 11P (WINSTON), LOCATED APPROXIMATELY 121 NM
NORTHWEST OF NIUE, HAS TRACKED EASTWARD AT 04 KNOTS OVER THE PAST
SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS DEEP
BANDS OF CONVECTION WITH DENSE OVERCAST OBSCURING AN EYE OBSERVED
PREVIOUSLY. A 170548Z SSMIS 91 GHZ MICROWAVE IMAGE SHOWS A SMALL
WELL-DEFINED LOW LEVEL CIRCULATION CENTER, GIVING HIGH CONFIDENCE TO
THE INITIAL POSITION, WITH NO NOTICEABLE IMPROVEMENT IN THE STRENGTH
OR ORGANIZATION IN THE CONVECTIVE STRUCTURE IN THE LAST SIX HOURS.
THE INITIAL INTENSITY IS ASSESSED AT 90 KNOTS AND IS BASED ON DVORAK
ESTIMATES FROM PGTW AND KNES REPORTING CURRENT INTENSITIES OF T5.0
(90 KNOTS). RECENT ANIMATED CIMSS MIMIC-TPW IMAGERY SHOWS A THIN
BAND OF DRY AIR BEGINNING TO BE ENTRAINED INTO TC WINSTON, WHICH
EXPLAINS THE LACK OF INTENSIFICATION OBSERVED IN THE LAST SIX HOURS
AND WILL HAMPER THE RATE OF INTENSIFICATION IN THE FUTURE. HOWEVER,
SEA SURFACE TEMPERATURES ARE HIGH (30 CELSIUS), AND FAVORABLE UPPER-
LEVEL CONDITIONS WILL PERSIST THROUGHOUT THE FORECAST WITH LOW (10
TO 15 KNOTS) VERTICAL WIND SHEAR AND SUFFICIENT DIVERGENCE ALOFT. TC
WINSTON IS EXPECTED TO INTENSIFY TO 115 KNOTS BY TAU 36. TC WINSTON
IS CURRENTLY ENTERING A WEAK STEERING ENVIRONMENT AND WILL REMAIN
QUASI-STATIONARY FOR THE NEXT 24 TO 36 HOURS BEFORE A RIDGE
EXTENSION BUILDS SOUTH AND STEERS WINSTON ALONG A WESTWARD TRACK. BY
TAU 48 A TROUGH TO THE WEST WILL WEAKEN THE WESTERN RIDGE AND ALLOW
A SECONDARY RIDGE POSITIONED TO THE NORTHEAST OF THE CYCLONE TO
ASSUME STEERING, TURNING TC WINSTON TO THE SOUTHEAST BY TAU 72.
DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT ON THE GENERAL TRACK,
BUT MODELS VARY GREATLY IN THE TIMING OF THE TURNS, GIVING LOW
CONFIDENCE TO THE FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
170600Z IS 28 FEET. NEXT WARNINGS AT 171500Z, 172100Z, 180300Z AND
180900Z.
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Winston currently still a high-end Cat 3 - central pressure 957 hPa, max-winds 160 km/h
Interestingly, the last 12Z GFS run has Winstone scraping the south of Fiji's main island of Viti Levu on Saturday night, and later making a direct hit on Cape Reinga in about 10 days time (await the media-frenzy), though no doubt that will change…
TROPICAL DISTURBANCE ADVISORY NUMBER A30 ISSUED FROM RSMC NADI
Feb 171935 UTC.
SEVERE TROPICAL CYCLONE WINSTON CENTRE 957HPA CATEGORY 3 WAS LOCATED
NEAR 17.0 SOUTH 170.6 WEST AT 171800 UTC. POSITION FAIR BASED ON HR
GOES EIR AND PERIPHERAL SURFACE OBSERVATIONS. CYCLONE MOVING
EAST-NORTHEAST AT 05 KNOTS. EXPECT SUSTAINED WINDS OF 85 KNOTS CLOSE
TO THE CENTRE.
…
DEEP CONVECTION REMAINS PERSISTENT.ORGANIZATION REMAINS GOOD. SST
AROUND 29-30 DEGREES CELSIUS. SYSTEM LIES UNDER A MODERATE UPPER
DIVERGENCE REGION IN LOW TO MODERATE SHEARED ENVIRONMENT. OUTFLOW
GOOD TO THE EAST. DVORAK ANALYSIS BASED ON EMBEDDED CENTRE PATTERN
WITH LLCC EMBEDDED IN W YEILDS DT=5.0, MET=5.0, PT=5.0.
FT BASED ON MET. THUS YIELDING T5.0/5.0/D0.5/24HRS.
FORECASTS :
AT 12 HRS VALID AT 180600 UTC 17.1S 170.7W SLOW MOV WITH 90KT CLOSE
TO CENTRE
AT 24 HRS VALID AT 181800 UTC 17.4S 171.6W MOV WSW AT 03KT WITH 95 KT
CLOSE TO CENTRE
OUTLOOK :
AT 36 HRS VALID AT 190600 UTC 17.7S 173.0W MOV WSW AT 06KT WITH 100
KT CLOSE TO CENTRE
AT 48 HRS VALID AT 191800 UTC 18.0S 174.5W MOV WSW AT 07KT WITH 95 KT
CLOSE TO CENTRE
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Winston upgraded Cat 4 late this morning - central pressure 953 hPa, max-winds 170 km/h.
RSMAC Nadi also going for Cat 5 by Friday morning…
TROPICAL DISTURBANCE ADVISORY NUMBER A30 ISSUED FROM RSMC NADI
Feb 172234 UTC.
SEVERE TROPICAL CYCLONE WINSTON CENTRE 953HPA CATEGORY 4 WAS LOCATED
NEAR 17.0 SOUTH 170.9 WEST AT 172100 UTC. POSITION FAIR BASED ON HR
GOES EIR AND PERIPHERAL SURFACE OBSERVATIONS. CYCLONE MOVING
NORTH-NORTHWEST AT 02 KNOTS. EXPECT SUSTAINED WINDS OF 90 KNOTS CLOSE
TO THE CENTRE.
…
DEEP CONVECTION REMAINS PERSISTENT WITH EYE DISCERNIBLE ON VIS
IMAGERY.ORGANIZATION REMAINS GOOD. SST AROUND 30 DEGREES CELSIUS.
SYSTEM LIES UNDER A MODERATE UPPER DIVERGENCE REGION IN LOW TO
MODERATE SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE EAST. DVORAK
ANALYSIS BASED ON B EYE IN CMG SURROUND WITH EYE ADJUSTMENT YEILDS
DT=6.0, MET=5.5, PT=5.5. FT BASED ON MET. THUS YIELDING
T5.5/5.5/D1.5/24HRS.
FORECASTS :
AT 12 HRS VALID AT 180900 UTC 17.1S 171.4W SLOW MOV W AT 02KT WITH
95KT CLOSE TO CENTRE
AT 24 HRS VALID AT 182100 UTC 17.3S 172.5W MOV WSW AT 05KT WITH 100
KT CLOSE TO CENTRE
OUTLOOK :
AT 36 HRS VALID AT 190900 UTC 17.7S 174.0W MOV WSW AT 08KT WITH 110
KT CLOSE TO CENTRE
AT 48 HRS VALID AT 192100 UTC 18.2S 175.7W MOV WSW AT 08KT WITH 105
KT CLOSE TO CENTRE
WTPS31 PGTW 172100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 11P (WINSTON) WARNING NR 019//
RMKS/
1. TROPICAL CYCLONE 11P (WINSTON) WARNING NR 019
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
171800Z --- NEAR 17.2S 170.8W
MOVEMENT PAST SIX HOURS - 090 DEGREES AT 02 KTS
POSITION ACCURATE TO WITHIN 030 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
…
REMARKS:
172100Z POSITION NEAR 17.2S 170.8W.
TROPICAL CYCLONE (TC) 11P (WINSTON), LOCATED APPROXIMATELY 125 NM
NORTH-NORTHWEST OF NIUE, HAS TRACKED EASTWARD AT 02 KNOTS OVER
THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY
DEPICTS DEEPENED CENTRAL CONVECTION ASSOCIATED WITH A CONSOLIDATING
LOW-LEVEL CIRCULATION CENTER. A 171759Z SSMIS MICROWAVE IMAGE ALSO
REVEALS TIGHTLY-CURVED BANDING WRAPPING INTO AN APPARENT MICROWAVE
EYE, SUPPORTING THE HIGH CONFIDENCE IN THE CURRENT POSITION. THE
INITIAL INTENSITY OF 95 KNOTS IS BASED ON AN OVERALL ASSESSMENT OF
DVORAK INTENSITY ESTIMATES FROM ALL REPORTING AGENCIES AND THE
IMPROVED STRUCTURE. UPPER-LEVEL ANALYSIS INDICATES WINSTON IS
LOCATED IN A FAVORABLE ENVIRONMENT WITH LOW (10 TO 15 KNOT) VERTICAL
WIND SHEAR AND GOOD POLEWARD OUTFLOW. ADDITIONALLY, SEA SURFACE
TEMPERATURES (30 DEGREES CELSIUS) ARE CONDUCIVE FOR FURTHER
DEVELOPMENT. FAVORABLE CONDITIONS ARE FORECAST TO PERSIST, ALLOWING
STEADY INTENSIFICATION OVER THE NEXT 36 HOURS, LEADING TO A PEAK
INTENSITY OF 115 KNOTS. AFTER TAU 48, UPPER-LEVEL CONDITIONS WILL
SLOWLY DEGRADE, LEADING TO ITS WEAKENING TREND. SLOW AND/OR QUASI-
STATIONARY MOVEMENT IS EXPECTED AS TC WINSTON REMAINS IN A WEAK
STEERING ENVIRONMENT FOR THE NEXT 12 TO 18 HOURS. DYNAMIC MODEL
GUIDANCE IS OVERALL IN FAIR AGREEMENT ON THE GENERAL TRACK IN THE
NEAR TERM, BUT VARIES GREATLY IN THE TIMING OF THE TURN. IN THE
EXTENDED TAUS, THERE IS SIGNIFICANT SPREAD AMONG AVAILABLE TRACKERS.
FOR THIS REASON, THE JTWC TRACK CONFIDENCE LEVEL REMAINS LOW.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 171800Z IS 28 FEET. NEXT WARNINGS
AT 180300Z, 180900Z, 181500Z AND 182100Z.//
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Thank you for the work being carried out in this topic, it makes very interesting reading. Was looking at the Colour IR Loop and noticed that there is a lot of red on it. Is that normal for this time of year?
basicly
red means cold...which means the CB's are reaching very high ..i.e they have cold tops.....generally the colder the colour (red) then the more severe the thunderstorm (i.e cyclone) is...because the cloud tops have grown to a large height..even reaching the troposphere
interestingly, if a cyclone is under an upper level high pressure system, then that can actually help it, by providing good outflow (winds spiralling out the opposite way)
Winston has increased in strength only slightly since about midday yesterday as he begins his westward track, and has developed a very large ragged eye overnight. Last night both JTWC and RSMAC Nadi dropped the prospect of Winston reaching Cat 5. Central pressure earlier this morning was 945 hPa, with max winds of around 170 km/h. Winston is looking increasingly likely to at least pass very close to the south of Fiji's main island of Viti Levu on Sunday.
TROPICAL DISTURBANCE ADVISORY NUMBER A33 ISSUED FROM RSMC NADI
Feb 181400 UTC.
SEVERE TROPICAL CYCLONE WINSTON CENTRE 945HPA CATEGORY 4 WAS LOCATED
NEAR 17.3S 172.4W AT 181200 UTC. POSITION FAIRR BASED ON HR GOES EIR
AND PERIPHERAL SURFACE REPORTS. CYCLONE MOVING WEST AT ABOUT 05
KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE ESTIMATED AT
ABOUT 95 KNOTS.
…
EYE PARTIALLY CLOUD FILLED BUT STILL DISCERNIBLE. DEEP CONVECTION
REMAINS PERSISTENT WITH CLOUD TOPS COOLING PAST 6 HOURS HOURS.
ORGANIZATION REMAINS GOOD. SST AROUND 29-30 DEGREES CELSIUS. SYSTEM
LIES IN LOW SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE SOUTH. DVORAK
ANALYSIS BASED ON OW EYE SURROUNDED BY B WITH NO EYE ADJUSTMENT FOR
LARGE EYE YEILDS DT=5.5, MET AND PT AGREE, FT BASED ON DT. THUS
YIELDING T5.5/5.5/D0.5/24HRS.
FORECASTS :
AT 12 HRS VALID AT 190000 UTC 17.6S 174.0W MOV WSW AT 08KT WITH 100
KT CLOSE TO CENTRE
AT 24 HRS VALID AT 191200 UTC 17.9S 175.8W MOV W AT 09KT WITH 105 KT
CLOSE TO CENTRE
OUTLOOK :
AT 36 HRS VALID AT 200000 UTC 18.2S 177.8W MOV W AT 09KT WITH 100 KT
CLOSE TO CENTRE
AT 48 HRS VALID AT 201200 UTC 18.5S 179.6W MOV W AT 09KT WITH 95 KT
CLOSE TO CENTRE
WTPS31 PGTW 181500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 11P (WINSTON) WARNING NR 022//
RMKS/
1. TROPICAL CYCLONE 11P (WINSTON) WARNING NR 022
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
181200Z --- NEAR 17.1S 172.3W
MOVEMENT PAST SIX HOURS - 270 DEGREES AT 07 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
…
REMARKS:
181500Z POSITION NEAR 17.1S 172.7W.
TROPICAL CYCLONE (TC) 11P (WINSTON), LOCATED APPROXIMATELY 182 NM
NORTHWEST OF NIUE, HAS TRACKED WESTWARD AT 07 KNOTS OVER THE PAST
SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY REVEALS A
LARGE, RAGGED EYE WITH CLOUD-TOP COOLING OBSERVED WITHIN THE EYE
WALL OVER THE PAST 6-HOURS. A 180951Z GPM 36 GHZ IMAGE DEPICTS A
LARGE MICROWAVE EYE WITH TIGHTLY CURVED, DEEP CONVECTIVE BANDING
WRAPPING INTO THE SYSTEM. THE INITIAL INTENSITY IS ASSESSED AT 100
KNOTS BASED UPON DVORAK CURRENT INTENSITY ESTIMATES OF T5.5 (102
KNOTS) FROM MULTIPLE AGENCIES. UPPER LEVEL ANALYSIS INDICATES A
FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH A GOOD POLEWARD OUTFLOW
CHANNEL AND WEAK (5 TO 10 KNOTS) VERTICAL WIND SHEAR (VWS). TC
WINSTON HAS BEGUN TO PICK UP FORWARD SPEED AFTER BEING QUASI-
STATIONARY OVER THE PAST 24 HOURS, AS IT TRACKS ALONG THE NORTHERN
PERIPHERY OF A BUILDING RIDGE TO THE SOUTH. AFTER TAU 48, THE SYSTEM
WILL BEGIN TO RE-CURVE TO THE SOUTH AND THEN SOUTHEAST BY TAU 120,
AS THE RIDGE RE-ORIENTS POLEWARD AND A TROUGH APPROACHES FROM THE
WEST. TC 11P IS FORECAST TO STRENGTHEN SLIGHTLY FROM TAU 12 TO 24,
AS VWS REMAINS WEAK, AND SSTS REMAIN FAVORABLE. AFTER TAU 24, THE
SYSTEM WILL WEAKEN GRADUALLY AS IT TRACKS OVER COLDER SSTS. TC
WINSTON WILL BEGIN TO WEAKEN MORE RAPIDLY AFTER TAU 48 AS IT MOVES
OVER AN AREA WITH INCREASING VWS. DYNAMIC MODEL GUIDANCE HAS SHOWN
IMPROVED CONFIDENCE AS INDIVIDUAL MEMBERS HAVE COME INTO BETTER
AGREEMENT WITH THE OVERALL SYNOPTIC STEERING PATTERN. THEREFORE,
THERE IS HIGH CONFIDENCE IN THE JTWC FORECAST TRACK. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 181200Z IS 28 FEET. NEXT
WARNINGS AT 182100Z AND 190300Z.//
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Yes, could be a bit touch and go for Fiji. Central pressure currently 940 hPa, max-winds 185 km/h.
JTWC now have a possible Cat 5 back on the cards by later today/tonight...
TROPICAL DISTURBANCE ADVISORY NUMBER A34 ISSUED FROM RSMC NADI
Feb 181951 UTC.
SEVERE TROPICAL CYCLONE WINSTON CENTRE 940HPA CATEGORY 4 WAS LOCATED
NEAR 17.5S 173.3W AT 181800 UTC. POSITION FAIR BASED ON HR GOES EIR
AND PERIPHERAL SURFACE REPORTS. CYCLONE MOVING WEST AT ABOUT 05
KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE ESTIMATED AT
ABOUT 100 KNOTS.
…
WELL DEFINED EYE VISIBLE ON SATELLITE IMAGERY. DEEP CONVECTION
REMAINS PERSISTENT. ORGANIZATION REMAINS GOOD. SST AROUND 30 DEGREES
CELSIUS. SYSTEM LIES IN LOW SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE
SOUTH. DVORAK ANALYSIS BASED ON OW EYE IN LG SURROUND WITH W RING
DT=6.0, MET AND PT AGREE, FT BASED ON MET. THUS YIELDING
T6.0/6.0/D1.0/24HRS.
FORECASTS :
AT 12 HRS VALID AT 190600 UTC 17.8S 174.9W MOV WSW AT 08KT WITH 100
KT CLOSE TO CENTRE
AT 24 HRS VALID AT 191800 UTC 18.1S 176.8W MOV W AT 09KT WITH 105 KT
CLOSE TO CENTRE
OUTLOOK :
AT 36 HRS VALID AT 200600 UTC 18.3S 178.7W MOV W AT 09KT WITH 105 KT
CLOSE TO CENTRE
AT 48 HRS VALID AT 201800 UTC 18.5S 179.7W MOV W AT 08KT WITH 100 KT
CLOSE TO CENTRE
WTPS31 PGTW 182100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 11P (WINSTON) WARNING NR 023//
RMKS/
1. TROPICAL CYCLONE 11P (WINSTON) WARNING NR 023
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 17.4S 173.3W
MOVEMENT PAST SIX HOURS - 250 DEGREES AT 10 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
...
REMARKS:
182100Z POSITION NEAR 17.5S 173.7W.
TROPICAL CYCLONE 11P (WINSTON), LOCATED APPROXIMATELY 219 NM
WEST-NORTHWEST OF NIUE, HAS TRACKED WEST-SOUTHWESTWARD AT 10
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY AND A 181723Z AMSU-B MICROWAVE IMAGE DEPICT A SYMMETRIC
SIGNATURE WITH AN APPARENT EYE FEATURE, SUPPORTING THE HIGH
CONFIDENCE IN THE CURRENT POSITION. THE INITIAL INTENSITY OF 105
KNOTS IS HEDGED SLIGHTLY HIGHER THAN CORRESPONDING DVORAK CURRENT
INTENSITY ESTIMATES OF T5.5 (102 KNOTS) FROM ALL REPORTING AGENCIES.
UPPER-LEVEL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT FOR
DEVELOPMENT WITH A GOOD POLEWARD OUTFLOW CHANNEL AND WEAK (5 TO 10
KNOT) VERTICAL WIND SHEAR (VWS). WINSTON IS CURRENTLY TRACKING
ALONG THE NORTHERN PERIPHERY OF A BUILDING RIDGE TO THE SOUTH. BY
TAU 72, THE SYSTEM WILL BEGIN TO TURN TO THE SOUTHEAST AND WILL
REMAIN ON A SOUTHEASTWARD TRAJECTORY THROUGH THE REMAINDER OF THE
FORECAST PERIOD. TC 11P IS FORECAST TO SLIGHTLY INTENSIFY AS
FAVORABLE CONDITIONS PERSIST. AFTER TAU 24, THE SYSTEM WILL WEAKEN
GRADUALLY AS IT TRACKS OVER COLDER SSTS. TC WINSTON WILL BEGIN TO
WEAKEN MORE RAPIDLY BY TAU 72 AS IT MOVES OVER AN AREA WITH
INCREASING VWS. DYNAMIC MODEL GUIDANCE HAS COME INTO BETTER
AGREEMENT WITH THE OVERALL SYNOPTIC STEERING PATTERN. THEREFORE,
THERE IS HIGH CONFIDENCE IN THE JTWC FORECAST TRACK. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 181800Z IS 30 FEET. NEXT WARNINGS AT
190900Z AND 192100Z.//
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Manukau heads obs wrote:Fiji could be starting to get the effects of TC Winston by tomorrow..and yet there is nothing in the Media here....
too much cry wolf lately?
You're quite right Brian. Winston has tracked directly westward today, rather than WSW, and appears to be making a bee-line for right between Fiji's 2 main islands of Viti Levu and Vanua Levu.
At around 4pm today Winstone was a high-end Cat 4 with a central pressure of 937 hPa and max winds of 195 km/h (could even be a Cat 5 by now).
TROPICAL DISTURBANCE ADVISORY NUMBER A36 ISSUED FROM RSMC NADI
Feb 190248 UTC.
SEVERE TROPICAL CYCLONE WINSTON CENTRE 937HPA CATEGORY 4 WAS LOCATED
NEAR 17.3S 174.7W AT 190000 UTC. POSITION FAIR BASED ON HR GOES EIR
AND PERIPHERAL SURFACE REPORTS. CYCLONE MOVING WEST AT ABOUT 09
KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE ESTIMATED AT
ABOUT 105 KNOTS.
…
WELL DEFINED EYE VISIBLE ON SATELLITE IMAGERY. DEEP CONVECTION
REMAINS PERSISTENT. ORGANIZATION REMAINS GOOD. SST AROUND 30 DEGREES
CELSIUS. SYSTEM LIES IN LOW SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE
SOUTH. DVORAK ANALYSIS BASED ON OW EYE IN B SURROUND WITH W RING
DT=6.0, MET AND PT AGREE, FT BASED ON MET. THUS YIELDING
T6.0/6.0/D0.5/24HRS.
FORECASTS :
AT 12 HRS VALID AT 191200 UTC 17.8S 176.3W MOV WSW AT 08KT WITH 105
KT CLOSE TO CENTRE
AT 24 HRS VALID AT 200000 UTC 18.1S 178.1W MOV WSW AT 09KT WITH 105
KT CLOSE TO CENTRE
OUTLOOK :
AT 36 HRS VALID AT 201200 UTC 18.3S 179.9E MOV W AT 09KT WITH 105 KT
CLOSE TO CENTRE
AT 48 HRS VALID AT 210000 UTC 18.5S 178.6E MOV W AT 07KT WITH 105 KT
CLOSE TO CENTRE
WTPS31 PGTW 190300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 11P (WINSTON) WARNING NR 024//
RMKS/
1. TROPICAL CYCLONE 11P (WINSTON) WARNING NR 024
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
190000Z --- NEAR 17.5S 174.6W
MOVEMENT PAST SIX HOURS - 265 DEGREES AT 12 KTS
POSITION ACCURATE TO WITHIN 015 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
…
REMARKS:
190300Z POSITION NEAR 17.6S 175.1W.
TROPICAL CYCLONE (TC) 11P (WINSTON), LOCATED APPROXIMATELY 401 NM
EAST OF SUVA, FIJI, HAS TRACKED WESTWARD AT 12 KNOTS OVER THE PAST
SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY CONTINUES TO
SHOW A SYMMETRIC SIGNATURE WITH A 15 NM EYE, SUPPORTING THE HIGH
CONFIDENCE IN THE CURRENT POSITION. THE INITIAL INTENSITY OF 110
KNOTS IS BASED ON DVORAK INTENSITY ESTIMATES RANGING FROM 102 TO 115
KNOTS FROM ALL REPORTING AGENCIES. UPPER-LEVEL ANALYSIS INDICATES A
FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH A GOOD POLEWARD OUTFLOW
CHANNEL AND WEAK (5 TO 10 KNOT) VERTICAL WIND SHEAR (VWS). WINSTON
IS CURRENTLY TRACKING ALONG THE NORTHERN PERIPHERY OF A BUILDING
RIDGE TO THE SOUTH. BY TAU 72, THE SYSTEM WILL BEGIN TO TURN TO THE
SOUTHEAST AND WILL REMAIN ON A SOUTHEASTWARD TRAJECTORY THROUGH THE
REMAINDER OF THE FORECAST PERIOD. TC 11P IS FORECAST TO SLIGHTLY
INTENSIFY AS FAVORABLE CONDITIONS PERSIST. AFTER TAU 24, THE SYSTEM
WILL WEAKEN GRADUALLY AS IT TRACKS OVER COLDER SSTS. TC WINSTON WILL
BEGIN TO WEAKEN MORE RAPIDLY BY TAU 72 AS IT MOVES OVER AN AREA WITH
INCREASING VWS. DYNAMIC MODEL GUIDANCE REMAINS IN GOOD AGREEMENT,
LENDING TO HIGH CONFIDENCE IN THE JTWC FORECAST TRACK WHICH IS
POSITIONED CLOSE TO MULTI-MODEL CONSENSUS. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 190000Z IS 30 FEET. NEXT WARNINGS AT 190900Z, 191500Z,
192100Z AND 200300Z.//
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Winston was upgraded to Cat 5 this evening - central pressure 930 hPa, max winds about 205 km/h…
HURRICANE WARNING 044 ISSUED FROM RSMC NADI Feb 190711 UTC.
TROPICAL CYCLONE WINSTON CENTRE 930HPA CATEGORY 5 WAS LOCATED NEAR 17.5 SOUTH
176.1 WEST AT 190600 UTC.
POSITION GOOD.
REPEAT POSITION 17.5S 176.1W at 190600 UTC.
CYCLONE MOVING WEST AT 11 KNOTS. CYCLONE INTENSIFYING.
EXPECT SUSTAINED WINDS OF 110 KNOTS CLOSE TO THE CENTRE INCREASING TO 115 KNOTS
BY 191800 UTC.
...
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