04P( Sarai) now a CAT 1 US, tracking apprx 190km South of Suva/Fiji



TC 04P. CLICK TO ANIMATE.

TC 04P( SARAI) SOUTH PACIFIC
As of 00:00 UTC Dec 28, 2019:

Location: 19.6°S 177.5°E
Maximum Winds: 65 kt ( 120km/h)
Gusts: 80 kt ( 150km/h)
CATEGORY US: 1

REMARKS:
280300Z POSITION NEAR 19.7S 177.7E.
28DEC19. TROPICAL CYCLONE 04P (SARAI), LOCATED APPROXIMATELY 103
NM SOUTH-SOUTHWEST OF SUVA, FIJI, HAS TRACKED EAST-SOUTHEASTWARD
AT 09 KNOTS OVER THE PAST SIX HOURS.  ANIMATED MULTISPECTRAL
SATELLITE IMAGERY REVEALS CONVECTION WRAPPING AROUND THE LOW LEVEL
CIRCULATION CENTER (LLCC). A 280117Z ATMS 88.2GHZ MICROWAVE IMAGE
DEPICTS A BROAD 45 NM DIAMETER MICROWAVE EYE FEATURE AND SUPPORTS
THE INITIAL POSITION WITH FAIR CONFIDENCE DUE TO THE LARGE SIZE.
THE INITIAL INTENSITY OF 65 KTS IS BASED ON PGTW AND KNES DVORAK
CURRENT INTENSITY ESTIMATES OF T4.0 (65 KTS). THE ENVIRONMENT IS
SOMEWHAT FAVORABLE WITH DECENT POLEWARD OUTFLOW, MODERATE (15-20
KT) VERTICAL WIND SHEAR (VWS), AND WARM (27 CELSIUS) SEA SURFACE
TEMPERATURES (SSTS). THE CYCLONE HAS THE POTENTIAL TO INTENSIFY
OVER THE NEXT 12 HOURS BEFORE COOLER SSTS, CONTINUED MODERATE TO
STRONG VWS, AND MINIMAL UPPER LEVEL OUTFLOW WILL CAUSE THE
INTENSITY TO WEAKEN. TC 04P IS TRACKING ALONG THE SOUTHWEST
PERIPHERY OF A POLEWARD EXTENSION OF A NEAR EQUATORIAL RIDGE
(NER). THERE IS A TROUGH APPROACHING FROM THE WEST THAT IS
EXPECTED TO WEAKEN THE NER AND SIGNIFICANTLY AFFECT THE TRACK OF
TC 04P. THE MODELS HANDLE THE TIMING AND DEPTH OF THIS TROUGH AND
THE ASSOCIATED WEAKENING/REORIENTATION OF THE NER DIFFERENTLY,
LEADING TO A WIDE VARIATION IN THE MODEL TRACK GUIDANCE. NOTABLY,
THE 12Z RUN OF ECMWF NOW TRACKS TC 04P TO THE NORTH BRINGING IT
OVER FIJI BETWEEN TAUS 72 AND 96. FURTHERMORE, THE 18Z RUNS OF THE
GFS, GFS ENSEMBLE, AND NAVGEM RECURVE THE SYSTEM AROUND TAU 72 AND
START TRACKING TC 04P NORTHEAST TOWARDS AMERICAN SAMOA. MEANWHILE,
THE 12Z UK MET AND UK MET ENSEMBLE CONTINUE A DUE EASTERLY TRACK,
WHICH WAS DOMINANT PRIOR TO THE 272100Z JTWC WARNING. THEREFORE,
THE JTWC TRACK CONTINUES TO BE PULLED NORTHEAST OF THE PREVIOUS
FORECAST TRACK NEAR THE MULTI-MODEL CONSENSUS. DUE TO THE
EXTREMELY HIGH UNCERTAINTY IN THE MODEL GUIDANCE, THERE IS LOW
CONFIDENCE IN THE JTWC TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 280000Z IS 25 FEET. NEXT WARNINGS AT 280900Z, 281500Z,
282100Z AND 290300Z.//
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PEAK INTENSITY OF 70KNOTS FORECAST WITHIN 12H


TRACK AND INTENSITY GUIDANCE


Rédigé par PATRICK HOAREAU le Samedi 28 Décembre 2019 à 07:58