TC 22S(HEROLD): CAT 1 US and intensifying and TC 23P(GRETEL): updates at 15/09UTC



15/10UTC ANIMATION. TC 22S. CONVECTION BEGINNING TO BUILD BACK NEAR THE CENTER.

TC 22S(HEROLD) SOUTH INDIAN
As of 06:00 UTC Mar 15, 2020:
Location: 15.1°S 51.8°E
Maximum Winds: 70 kt ( 130km/h)
Gusts: 85 kt ( 160km/h)
Minimum Central Pressure: 983 mb
CATEGORY US: 1

TPXS10 PGTW 150924
A. TROPICAL CYCLONE 22S (HEROLD)
B. 15/0845Z
C. 15.07S
D. 51.97E
E. FIVE/MET8
F. T4.0/4.0/D0.5/24HRS  STT: S0.0/03HRS
G. IR/EIR/VIS/MSI
H. REMARKS: 36A/PBO LARGE EYE/ANMTN. OW EYE SURROUNDED BY OW
YIELDS AN E# AND DT (NO EYE ADJUSTMENT) OF 4.0. MET AND PT
AGEE. DBO DT.
I. ADDITIONAL POSITIONS: NONE
 ELIAS
REMARKS:
150900Z POSITION NEAR 15.1S 52.1E.
15MAR20. TROPICAL CYCLONE (TC) 22S (HEROLD), LOCATED APPROXIMATELY
336 NM NORTHEAST OF ANTANANARIVO, MADAGASCAR, HAS TRACKED EASTWARD
AT 05 KNOTS (KTS) OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY (MSI) REVEALS THINNING CONVECTION OVER THE CENTER
OF THE SYSTEM, BUT CONTINUED DEEP CONVECTION WITHIN THE POLEWARD
SEMICIRCLE. THE CONVECTION ALONG THE EQUATORWARD SIDE APPEARS TO
HAVE DIMINISHED, POSSIBLY DUE TO THE EFFECTS OF LAND INTERACTION
WITH MADAGASCAR. THE INITIAL POSITION IS BASED ON TIGHTLY WRAPPED
BANDING IN MSI ALONG WITH A 150436Z GMI 37 GHZ MICROWAVE IMAGE
SHOWING A DISTINCT MICROWAVE EYE FEATURE. FURTHERMORE, A 150622Z
METOP-B DIRECT ASCAT IMAGE PLACES GOOD CONFIDENCE IN THE INITIAL
POSITION. THE INITIAL INTENSITY OF 70 KTS IS SET WITH GOOD
CONFIDENCE BASED ON A 150358Z CIMSS SATCON ESTIMATE OF 71 KTS AND AN
ADVANCED DVORAK TECHNIQUE ESTIMATE OF T4.2 (70 KTS), WHICH IS
CONSISTENT WITH, ALTHOUGH SLIGHTLY HIGHER THAN, MULTI-AGENCY DVORAK
CURRENT INTENSITY ESTIMATES OF T4.0 (65 KTS, PGTW/KNES/FMEE). UPPER
LEVEL ANALYSIS REVEALS LOW (5-10 KT) VERTICAL WIND SHEAR (VWS) AND
ESTABLISHED EQUATORWARD AND POLEWARD OUTFLOW CHANNELS. PAIRED WITH
WARM (28-29 CELSIUS) SEA SURFACE TEMPERATURES, TC 22S IS LOCATED
WITHIN AN OVERALL FAVORABLE ENVIRONMENT. THE SYSTEM HAS STARTED TO
MOVE SLOWLY EASTWARD UNDER THE STEERING INFLUENCE OF A NEAR
EQUATORIAL RIDGE (NER) BUILDING IN TO THE NORTHEAST. AS THE NER
CONTINUES TO BUILD, TC 22S WILL TRACK ALONG ITS PERIPHERY AND
ACCELERATE EAST-SOUTHEASTWARD TO SOUTHEASTWARD FOR THE REMAINDER OF
THE FORECAST. THE HIGHLY FAVORABLE ENVIRONMENT WILL ALLOW THE SYSTEM
TO INTENSIFY TO A PEAK OF 95 KTS BY TAU 36. THE POSSIBILITY OF RAPID
INTENSIFICATION DURING THIS PERIOD COULD ALLOW FOR A HIGHER PEAK
INTENSITY. AFTERWARDS, INCREASING VWS AND COOLING SST WILL BEGIN TO
WEAKEN TC 22S AND THE SYSTEM WILL BEGIN SUBTROPICAL TRANSITION (STT)
AS IT INTERACTS WITH THE MID-LATITUDE BAROCLINIC ZONE. STT
COMPLETION IS ANTICIPATED BY TAU 96. NUMERICAL MODEL GUIDANCE
REMAINS IN GENERALLY GOOD AGREEMENT. HOWEVER, SPREAD INCREASES
THROUGHOUT THE FORECAST PERIOD TO 275 NM BY TAU 96. DUE TO THIS
MODEL SPREAD AND THE UNCERTAINTY REGARDING THE TIMING OF THE
ACCELERATION OF THE SYSTEM, THERE IS LOW CONFIDENCE IN THE JTWC
TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 150600Z IS 20
FEET. NEXT WARNINGS AT 152100Z AND 160900Z.//
NNNN

TC 23P(GRETEL) SOUTH PACIFIC
As of 06:00 UTC Mar 15, 2020:
Location: 21.7°S 163.3°E
Maximum Winds: 55 kt ( 100km/h)
Gusts: 70 kt ( 130km/h)
Minimum Central Pressure: 980 mb

TPPS10 PGTW 150945
A. TROPICAL CYCLONE 23P (GRETEL)
B. 15/0900Z
C. 22.50S
D. 164.39E
E. FIVE/HMWRI8
F. T3.5/3.5/D1.5/24HRS  STT: S0.0/03HRS
G. IR/EIR
H. REMARKS: 38A/PBO SBC/ANMTN. CNVCTN WRAPS .80 ON LOG10 SPIRAL
YIELDING A DT OF 3.5. MET AND PT AGREE. DBO DT.
I. ADDITIONAL POSITIONS: NONE
ELIASREMARKS:
150900Z POSITION NEAR 22.5S 164.3E.
15MAR20. TROPICAL CYCLONE (TC) 23P (GRETEL), LOCATED APPROXIMATELY 158
NM WEST OF NOUMEA, NEW CALEDONIA, HAS TRACKED SOUTHEASTWARD AT 21
KNOTS (KTS) OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) DEPICTS DEEP CONVECTION WRAPPING TIGHTLY INTO A MOSTLY-
OBSCURED LOW LEVEL CIRCULATION CENTER. THIS MSI COMBINED WITH A
150522Z SSMIS 37 GHZ MICROWAVE IMAGE REVEALING A MICROWAVE EYE FEATURE
LEND HIGH CONFIDENCE TO THE INITIAL POSITION. THE INITIAL INTENSITY OF
55 KTS IS BASED ON MULTI-AGENCY DVORAK CURRENT INTENSITY ESTIMATES OF
T3.0-3.5 (45-55 KTS, PGTW/KNES/PHFO/NFFN) AND A 150510Z ADVANCED
DVORAK TECHNIQUE ESTIMATE OF T3.3 (51 KTS) WITH GOOD CONFIDENCE.
EXCELLENT POLEWARD OUTFLOW, MODERATE (10-20 KT) VERTICAL WIND SHEAR
(VWS), AND WARM (28-29 CELSIUS) SEA SURFACE TEMPERATURES CONTRIBUTE TO
AN OVERALL MARGINALLY FAVORABLE ENVIRONMENT FOR CONTINUED DEVELOPMENT.
TC 23P IS TRACKING ALONG THE SOUTHWEST PERIPHERY OF A NEAR EQUATORIAL
RIDGE. UNDER ITS STEERING INFLUENCE, THE SYSTEM IS FORECAST TO FOLLOW
A SOUTHEASTWARD THEN EAST-SOUTHEASTWARD TRACK FOR THE REMAINDER OF THE
FORECAST PERIOD. THE CURRENT ENVIRONMENT SHOULD ALLOW TC 23P A BRIEF
PERIOD OF SLIGHT INTENSIFICATION TO 60 KTS PRIOR TO THE ONSET OF
STRONG VWS AFTER TAU 12. AT THIS POINT, THE SYSTEM WILL BEGIN TO
WEAKEN SLOWLY AND BEGIN EXTRATROPICAL TRANSITION (ETT) AS IT INTERACTS
WITH THE BAROCLINIC ZONE LOCATED TO THE SOUTH. ETT COMPLETION IS
EXPECTED BY TAU 48 WITH TC 23P BECOMING A GALE STRENGTH, COLD CORE
LOW. NUMERICAL MODEL GUIDANCE IS IN EXCELLENT AGREEMENT THROUGHOUT THE
FORECAST PERIOD, WITH A CROSS-TRACK SPREAD OF 90 NM AT TAU 48.
THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC TRACK FORECAST.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 150600Z IS 36 FEET. NEXT WARNINGS
AT 151500Z, 152100Z, 160300Z AND 160900Z.//
NNNN
 

TC 22S: WARNING 5: FORECAST TO REACH 95KTS ( CAT 2 US) BY 36H. THE POSSIBILITY OF RAPID INTENSIFICATION DURING THIS PERIOD COULD ALLOW FOR A HIGHER PEAK INTENSITY.


TC 22S: TRACK AND INTENSITY GUIDANCE


TC 23P: WARNING 3. FORECAST TO INTENSIFY TO PEAK NEAR 60KTS WITHIN 12H.


TC 23P: TRACK AND INTENSITY GUIDANCE


TC 22S: 15/0622UTC


TC 23P: 15/0543UTC


 

15/0515UTC


15/00UTC

Rédigé par PATRICK HOAREAU le Dimanche 15 Mars 2020 à 14:22