04P( Sarai) near peak intensity: 70knots, Cat1 US. Should be weakening rapidly after 36h



TC 04P. CLICK TO ANIMATE.

TC 04P( SARAI) SOUTH PACIFIC
As of 12:00 UTC Dec 28, 2019:

Location: 19.8°S 178.3°E
Maximum Winds: 70 kt ( 130km/h)
Gusts: 85 kt ( 160km/h)
CATEGORY US: 1

REMARKS:
281500Z POSITION NEAR 19.8S 178.6E.
28DEC19. TROPICAL CYCLONE (TC) 04P (SARAI), LOCATED APPROXIMATELY
102 NM SOUTH OF SUVA, FIJI, HAS TRACKED NORTHEASTWARD AT 07 KNOTS (KTS)
OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE
IMAGERY REVEALS CONVECTION WRAPPING INTO A LOW LEVEL CIRCULATION
CENTER (LLCC) WHICH BRIEFLY DEVELOPED AN EYE, SUPPORTING GOOD
CONFIDENCE IN THE INITIAL POSITION. THE EYE APPEARED JUST PRIOR TO
THE VALID TIME OF THIS FORECAST. THE EYE HAS SINCE DISAPPEARED, BUT
CONTINUES TO ATTEMPT TO REFORM. THE INITIAL INTENSITY IS SET AT 70
KTS WITH GOOD CONFIDENCE, HEDGED BETWEEN A 281140Z ADVANCED DVORAK
TECHNIQUE INTENSITY ESTIMATE OF T4.1 (67 KTS) AND DVORAK CURRENT
INTENSITY ESTIMATES OF T4.5 (77 KTS) BY PGTW/KNES AND T4.0 (65 KTS)
BY NFFN. TC 04P REMAINS IN A FAVORABLE ENVIRONMENT WITH MODERATE (15-
20 KT) VERTICAL WIND SHEAR (VWS), WARM (27-28 CELSIUS) SEA SURFACE
TEMPERATURE (SST), AND EXCELLENT POLEWARD OUTFLOW. TC 04P IS
TRACKING ALONG THE SOUTHWEST PERIPHERY OF A POLEWARD EXTENSION OF A NEAR
EQUATORIAL RIDGE (NER). A TROUGH APPROACHING FROM THE WEST IS
EXPECTED TO WEAKEN THE NER, IMPACTING THE FORECAST TRACK. HOWEVER,
THERE ARE DIFFERENCES IN THE TIMING AND DEPTH OF THE TROUGH IN THE
MODELS WHICH RESULTS IN VARIATION IN THE WEAKENING OF THE NER. THE
MODEL SOLUTIONS HAVE COME INTO BETTER AGREEMENT SINCE THE PREVIOUS
WARNING. NOTABLY, THE GFS AND GFS ENSEMBLE SOLUTIONS DEPICT AN
EASTWARD TRACK THROUGH TAU 48 FOLLOWED BY A SHORT NORTHEASTWARD
COURSE PRIOR TO RECURVING THE SYSTEM SOUTHEASTWARD AS IT BEGINS TO
INTERACT WITH THE PASSING TROUGH. NAVGEM AND ECMWF CONTINUE TO TURN
TC 04P TO A NORTHEASTWARD TRACK FURTHER WEST THAN THE OTHER MODEL
SOLUTIONS. MOST MODELS ARE IN AGREEMENT THAT THE SYSTEM WILL SHIFT
TO A NORTHEASTWARD TRACK. HOWEVER, THE TIMING OF THE TROUGH PASSAGE AND
THE DEPTH OF THE TROUGH ARE CREATING SPREAD IN THE NUMERICAL MODEL
SOLUTIONS. UKMET AND UKMET ENSEMBLE REMAIN THE OUTLIERS WHICH DEPICT
A STEADY EASTWARD TRACK PRIOR TO TROUGH INTERACTION. JTWC TRACK
FORECAST IS PLACED NEAR THE MULTI-MODEL CONSENSUS. HOWEVER, THERE IS
LOW CONFIDENCE IN THE TRACK FORECAST DUE TO THE UNCERTAINTY IN THE
MODEL GUIDANCE. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 281200Z IS 28
FEET. NEXT WARNINGS AT 282100Z, 290300Z, 290900Z AND 291500Z.//
NNNN

INTENSITY DOES APPEAR TO HAVE PEAKED AT 70KNOTS/ CAT 1 US


TRACK AND INTENSITY GUIDANCE


 

Rédigé par PATRICK HOAREAU le Samedi 28 Décembre 2019 à 19:30