South Indian: TC 10S(DIANE) & TC 11S(ESAMI) updates + Invest 96P update



TC 10S(DIANE): WARNING 2. PEAK INTENSITY NEAR 50KT FORECAST WITHIN 24H.

TC 10S(DIANE) SOUTH INDIAN
As of 06:00 UTC Jan 25, 2020:
Location: 20.6°S 60.3°E
Maximum Winds: 45 kt ( 85km/h)
Gusts: 55 kt ( 100km/h)

Minimum Central Pressure: 1000 mb
REMARKS:
250900Z POSITION NEAR 20.9S 61.2E.
25JAN20. TROPICAL CYCLONE (TC) 10S (DIANE), LOCATED APPROXIMATELY
171 NM EAST OF PORT LOUIS, MAURITIUS, HAS TRACKED EAST-SOUTHEASTWARD
AT 16 KNOTS (KTS) OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY DEPICTS A TIGHTLY-WRAPPED LOW-LEVEL CIRCULATION
WITH DEEP CONVECTION OVERHEAD. THE INITIAL POSITION IS SUPPORTED BY
A 250516Z MHS 89 GHZ MICROWAVE IMAGE SHOWING A COMPACT SYSTEM. THE
INITIAL INTENSITY IS SET AT 45 KTS, SUPPORTED BY MULTI-AGENCY DVORAK
CURRENT INTENSITY ESTIMATES OF T3.0 (45 KTS) BY PGTW, FMEE, AND
KNES. A 250402Z PARTIAL METOP-A ASCAT PASS SHOWING A REGION OF 35-40
KNOT WINDS IN THE EASTERN SEMICIRCLE PLACES GOOD CONFIDENCE IN THE
CURRENT INTENSITY. ENVIRONMENTAL ANALYSIS REVEALS GOOD POLEWARD AND
EQUATORWARD OUTFLOW CHANNELS AND LOW (5-10 KTS) VERTICAL WIND SHEAR
(VWS). PAIRED WITH SST VALUES OF 28-29 CELSIUS, THE OVERALL
ENVIRONMENT REMAINS FAVORABLE FOR CONTINUED DEVELOPMENT. TC 10S IS
TRACKING EAST-SOUTHEASTWARD ALONG THE SOUTHERN PERIPHERY OF THE NEAR-
EQUATORIAL RIDGE POSITIONED TO THE NORTH. THE SYSTEM IS EXPECTED TO
MAINTAIN THIS TRACK THROUGH TAU 36 WITH GRADUAL INTENSIFICATION TO A
PEAK OF 50 KTS AROUND TAU 12. WARM SST WILL OFFSET THE INCREASING
VWS VALUES, ALLOWING TC 11S TO MAINTAIN NEAR-PEAK INTENSITY THROUGH
TAU 36. BEYOND TAU 36, THE SYSTEM IS EXPECTED TO SLOW AND GRADUALLY
TURN SOUTH-SOUTHEASTWARD AS THE STEERING ENVIRONMENT WEAKENS DUE TO
THE PRESENCE OF TC 11S TO THE EAST. AFTER TAU 72, THE SYSTEM IS
FORECAST TURN SOUTH-SOUTHWESTWARD AS A LOW-LEVEL SUBTROPICAL RIDGE
BUILDS TO THE SOUTH AND EAST OF THE SYSTEM. TC 10S WILL BEGIN TO
RAPIDLY WEAKEN AS COOLER (24-25 CELSIUS) SST AND STRONG (40-50 KTS)
VWS IMPACT THE SYSTEM. DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT
REGARDING THE OVERALL TRACK FORECAST. HOWEVER, THERE ARE VARIATIONS
REGARDING THE SPEED AND TIMING OF THE TURN. OVERALL, THERE IS LOW
CONFIDENCE IN THE JTWC FORECAST DUE TO THE COMPLEX AND EVOLVING
STEERING ENVIRONMENT. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 250600Z IS
15 FEET. NEXT WARNINGS AT 252100Z AND 260900Z. REFER TO TROPICAL
CYCLONE 11S (ESAMI) WARNINGS (WTXS32 PGTW) FOR UPDATES.//
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TC 11S(ESAMI) SOUTH INDIAN
As of 06:00 UTC Jan 25, 2020:
Location: 24.2°S 72.7°E
Maximum Winds: 45 kt ( 85km/h)
Gusts: 55 kt ( 100km/h)

Minimum Central Pressure: 999 mb
REMARKS:
250900Z POSITION NEAR 24.5S 73.1E.
25JAN20. TROPICAL CYCLONE (TC) 11S (ESAMI), LOCATED APPROXIMATELY 890
NM EAST-SOUTHEAST OF PORT LOUIS, MAURITIUS, HAS TRACKED EAST-
SOUTHEASTWARD AT 10 KNOTS (KTS) OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY DEPICTS A COMPACT AREA OF CONVECTION
OBSCURING THE LOW LEVEL CIRCULATION CENTER (LLCC). BASED ON AN
EXTRAPOLATION OF A 250451Z GMI 36 GHZ MICROWAVE IMAGE ALONG WITH
TIGHTLY-WRAPPING LOW LEVEL BANDING IN MSI, THE INITIAL POSITION IS
PLACED WITH GOOD CONFIDENCE. THE INITIAL INTENSITY IS SET AT 45 KTS
BASED ON A 250402Z PARTIAL METOP-A ASCAT IMAGE REVEALING A SWATH OF
40-45 KT WINDS WITHIN THE EASTERN SEMICIRCLE AND IS SUPPORTED BY
DVORAK CURRENT INTENSITY ESTIMATES OF T3.0 BY PGTW, FMEE, AND KNES.
TC 11S IS TRACKING THROUGH A MODERATELY FAVORABLE ENVIRONMENT FOR
CONTINUED DEVELOPMENT. ENVIRONMENTAL ANALYSIS REVEALS MODERATE (15-20
KTS) VERTICAL WIND SHEAR (VWS), WARM (26-27 CELSIUS) SEA SURFACE
TEMPERATURE (SST), AND ESTABLISHED DIVERGENCE ALOFT. BEING STEERED BY
A NEAR-EQUATORIAL RIDGE TO THE NORTH, TC 11S IS TRACKING EAST-
SOUTHEASTWARD AND IS FORECAST TO MAINTAIN THIS TRACK THROUGH TAU 24.  
AFTER THIS, THE SYSTEM WILL TURN TO A SOUTH-SOUTHEASTWARD TRACK
THROUGH TAU 48 WITH THE ALONG-TRACK SPEED SLOWING AS THE STEERING
RIDGE TO THE NORTH BEGINS TO WEAKEN. A STRONG SUBTROPICAL RIDGE TO
THE SOUTH WILL BUILD IN AND TAKE OVER AS THE PRIMARY STEERING FEATURE
FOR TC 11S, RESULTING IN THE SHARP RECURVE TO THE WEST BETWEEN TAU 48
AND 72. THE TIMING AND SPEED OF THIS TRACK CHANGE VARIES BETWEEN THE
GLOBAL MODEL SOLUTIONS. TC 11S WILL GRADUALLY WEAKEN AFTER TAU 36 AS
COOLING SST AND INCREASING VWS (>40 KTS) IMPACT THE SYSTEM, WITH
DISSIPATION OVER WATER BY TAU 96. OVERALL, THERE IS LOW CONFIDENCE IN
THE JTWC FORECAST TRACK DUE TO THE COMPLEX STEERING ENVIRONMENT.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 250600Z IS 13 FEET. NEXT WARNINGS
AT 252100Z AND 260900Z. REFER TO TROPICAL CYCLONE 10S (DIANE)
WARNINGS (WTXS31 PGTW) FOR UPDATES.//
NNNN


INVEST 96P SOUTH PACIFIC
As of 06:00 UTC Jan 25, 2020:
Location: 18.6°S 169.3°W
Maximum Winds: 30 kt ( 55km/h)
Gusts: 40 kt ( 75km/h)

Minimum Central Pressure: 1002 mb
ABPW10 PGTW 250600
2. SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST):
   A. TROPICAL CYCLONE SUMMARY: NONE.
   B. TROPICAL DISTURBANCE SUMMARY:
      (1) THE AREA OF CONVECTION (INVEST 96P) PREVIOUSLY LOCATED
NEAR 15.8S 168.9W IS NOW LOCATED NEAR 16.8S 169.1W, APPROXIMATELY
171 NM SOUTH-SOUTHWEST OF PAGO PAGO, AMERICAN SAMOA. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY SHOWS A BROAD AREA OF CONVECTION ON
THE EASTERN EDGE OF THE LOW LEVEL CIRCULATION CENTER (LLCC). A
250409Z 91GHZ SSMIS MICROWAVE IMAGE SHOWS POCKETS OF DEEP CONVECTION
LOCATED MAINLY TO THE EAST OF THE LLCC. ENVIRONMENTAL ANALYSIS SHOWS
THAT INVEST 96P HAS FAVORABLE VERTICAL WIND SHEAR (10 TO 15 KNOTS)
ALONG WITH A ROBUST POLEWARD OUTFLOW CHANNEL BUT A LIMITED
EQUATORWARD OUTFLOW CHANNEL. SEA SURFACE TEMPERATURES ARE FAVORABLE
FOR DEVELOPMENT, BETWEEN 28 AND 29 DEGREES CELSIUS. GLOBAL MODELS
INDICATE THAT 94P WILL CONTINUE TO TRACK SOUTHWARD AS IT SLOWLY
INTENSIFIES DUE TO FAVORABLE ENVIRONMENTAL CONDITIONS. MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1002 MB. THE POTENTIAL FOR
THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS REMAINS HIGH. SEE REF A (WTPS21 PGTW 242200) FOR FURTHER
DETAILS.
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TC 11S(ESAMI): WARNING 2. NEAR PEAK INTENSITY


01/25 0530UTC


TC 10S: TRACK AND INTENSITY GUIDANCE


TC 11S: TRACK AND INTENSITY GUIDANCE


INVEST 96P: TRACK AND INTENSITY GUIDANCE

Rédigé par PATRICK HOAREAU le Samedi 25 Janvier 2020 à 13:18