TC 24S(IRONDRO) intensifying ,TC 25P(HAROLD) intensifying rapidly. Updates at 04/03UTC



TC 24S . CLICK TO ANIMATE.

FNMOC
FNMOC
2020 APR 04 0315UTC SOUTH INDIAN & SOUTH PACIFIC
UPDATES
As of 00:00 UTC Apr 04, 2020:
Location: 20.8°S 76.8°E
Maximum Winds: 90 kt
Gusts : 110 kt
Minimum Central Pressure: 962 mb
CATEGORY US: 2
INTENSIFYING
TPXS10 PGTW 040326
A. TROPICAL CYCLONE 24S (IRONDRO)
B. 04/0300Z
C. 20.85S
D. 77.52E
E. THREE/MET8
F. T5.5/5.5/D2.0/24HRS  STT: D0.5/03HRS
G. IR/EIR/VIS/MSI
H. REMARKS: 11A/PBO RAGGED EYE/ANMTN. OW EYE SURROUNDED BY B
YIELDS AN E# OF 5.5. ADDED 0.5 EYE ADJUSTMENT FOR W, TO YIELD A
DT OF 6.0. MET YIELDS A 4.5 AND PT YIELDS A 5.5. DBO PT.
I. ADDITIONAL POSITIONS:
   03/2238Z  20.38S  76.28E  SSMS
BERMEA
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TC #25P #HAROLD SOUTH PACIFIC
As of 00:00 UTC Apr 04, 2020:
Location: 13.9°S 164.0°E
Maximum Winds: 90 kt
Gusts : 110 kt
Minimum Central Pressure: 966 mb
CATEGORY US: 2
INTENSIFYING
TPPS11 PGTW 040324
A. TROPICAL CYCLONE 25P (HAROLD)
B. 04/0300Z
C. 14.54S
D. 164.65E
E. THREE/HMWRI8
F. T6.0/6.0/D3.5/24HRS  STT: D1.0/03HRS
G. IR/EIR/VIS/MSI
H. REMARKS: 11A/PBO RAGGED EYE/ANMTN. MG EYE SURROUNDED BY W
YIELDS AN E# AND DT (NO EYE ADJUSTMENT) OF 6.0. MET YIELDS A
4.5 AND PT YIELDS A 5.5. DBO DT.
I. ADDITIONAL POSITIONS: NONE
BERMEA

REMARKS:
040300Z POSITION NEAR 14.1S 164.1E.
04APR20. TROPICAL CYCLONE 25P (HAROLD), LOCATED APPROXIMATELY 337
NM NORTHWEST OF PORT VILA, VANUATU, HAS TRACKED SOUTH-
SOUTHEASTWARD AT 04 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY CONFIRMS THAT TC HAROLD IS UNDERGOING
A PERIOD OF RAPID INTENSIFICATION, WITH DEEP CONVECTIVE BANDS WITH
VERY COLD CLOUD TOPS WRAPPING INTO A PINHOLE EYE, WHICH HAS DEVELOPED
OVER THE PAST FEW HOURS. THERE HAS BEEN NO GOOD MICROWAVE PASS SINCE
031911Z, BUT THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED
ON THE PINHOLE EYE FEATURE IN THE VISIBLE AND INFRARED BANDS. THE
INITIAL INTENSITY IS ASSESSED AT 90 KNOTS USING A COMBINATION OF
AGENCY DVORAK CURRENT INTENSITY ESTIMATES OF T5.0 (90 KNOTS) FROM ALL
AGENCIES (PGTW/PHFO/NFFN), AND AN ADVANCED DVORAK TECHNIQUE ESTIMATE
OF T4.8. ENVIRONMENTAL ANALYSIS INDICATES THAT TC 25P LIES IN A HIGHLY
FAVORABLE ENVIRONMENT, WITH VERY ROBUST DIRVERGENT OUTFLOW, WARM (29-
30 DEG CELSIUS) SSTS AND LOW TO MODERATE (15-20 KNOTS) VWS, WITH A
RELATIVE SHEAR VALUE MUCH LOWER DUE TO STORM MOTION AND SHEAR VECTORS
BEING IN PHASE. TC 25P HAS SLOWED SIGNFICANTLY OVER THE PAST SIX
HOURS, DUE TO THE DEVELOPMENT OF AN EXTENSION OF THE STR NOSING
SOUTHWESTWARD TO THE EAST OF THE SYSTEM, EFFECTIVELY LIMITING
EASTEWARD MOVEMENT OF TC 25P. THIS RIDGE IS FORECAST TO FURTHER
STRENGTHEN OVER THE NEXT 24-36 HOURS, WHICH WILL IN TURN LEAD TO VERY
SLOW, NEARLY QUASI-STATIONARY MOVEMENT TOWARDS THE SOUTH-SOUTHEAST OF
TC 25P. BEYOND TAU 48 THE AFOREMENTIONED EXTENSION OF THE STR WEAKENS
AND THE STR ITSELF REORIENTS TO A NORTHWEST-SOUTHEAST ORIENTATION,
ALLOWING TC 25P TO ACCELERATE SOUTHWEASTWARD THROUGH THE END OF THE
FORECAST PERIOD. TC 25P IS FORECAST TO CONTINUE TO RAPIDLY INTENSIFY
OVER THE NEXT 24-36 HOURS AS IT TAPS INTO HIGHLY DIVERGENT UPPER LEVEL
FLOW WHILE REMAINING IN A RELATIVELY LOW VWS ENVIRONMENT OVER VERY
WARM WATERS. AFTER PEAKING OUT AT 120 KNOTS BY TAU 48 THE ENVIRONMENT
WILL SLOWLY DETERIORATE AS THE SYSTEM EXPERIENCES INCREASING VWS AND
CONVERGENCE ALOFT, AND DECREASING SSTS. BY TAU 96, THE SYSTEM WILL
BEGIN TO INTERACT WITH MID-LATITUDE WESTERLIES AND BEGIN SUBTROPICAL
TRANSITION. NUMERICAL GUIDANCE ALL AGREE ON THE GENERAL SOUTHEASTWARD
TRACK AND SLOW FORWARD MOTION THROUGH TAU 48, BUT DIFFER ON THE
DEGREE, WITH SOME MODELS INDICATING A MOVEMENT DUE SOUTH OR EVEN
SOUTHWEST AT ONE OR TWO KNOTS BEFORE TURNING SOUTHEAST, WHILE OTHERS
MOVE STRAIGHT SOUTHEAST AT THREE TO FOUR KNOTS THROUGH THE ENTIRE
FORECAST. BEYOND TAU 48, MODELS COME INTO MUCH BETTER AGREEMENT ON
BOTH THE TRACK AND FORWARD MOTION. THE JTWC FORECAST FAVORS THE MORE
SOUTHWARD TRACK THROUGH TAU 48 AT ABOUT THREE KNOTS, BEFORE TURNING
SOUTHEAST AND ACCELERATING AFTER TAU 48. DUE TO THE OVERALL HIGH
UNCERTAINTY IN THE GUIDANCE IN THE FIRST 48 HOURS AND THE GENERAL
UNCERTAINTY IN THE STEERING ENVIRONMENT, THERE IS LOW CONFIDENCE IN
THE JTWC FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 040000Z IS
28 FEET.

TC 25P. CLICK TO ANIMATE.


TC 24S: TRACK AND INTENSITY GUIDANCE.


 

TC 25P. TRACK AND INTENSITY GUIDANCE.

Rédigé par PATRICK HOAREAU le Samedi 4 Avril 2020 à 07:45