03UTC: TC SAVANNAH(19S) is weakening over the open waters of the South Indian Ocean


Warning 17/JTWC


0430UTC
0430UTC
https://www.facebook.com/groups/1817419381676514/
TC SAVANNAH(19S)
As of 00:00 UTC Mar 18, 2019:

Location: 16.8°S 89.6°E
Maximum Winds: 85 kt ( 160km/h)
Gusts: 105kt ( 195km/h)

REMARKS:
180300Z POSITION NEAR 16.9S 89.3E.
TROPICAL CYCLONE (TC) 19S (SAVANNAH), LOCATED APPROXIMATELY 510 NM
SOUTHWEST OF COCOS ISLAND, HAS TRACKED WEST-SOUTHWESTWARD AT 06
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY SHOWS THE CONVECTIVE CLOUD TOP TEMPERATURES ARE WARMING AND
BEING SHEARED TO THE SOUTHEAST. THE INITIAL POSITION IS PLACED WITH
HIGH CONFIDENCE BASED ON A 172350Z SSMIS 37 GHZ MICROWAVE IMAGE
WHICH SHOWS THE UNDERLYING LOW LEVEL CIRCULATION CENTER IS ON THE
NORTHWESTERN SIDE OF THE CIRRUS SHIELD. THE INITIAL INTENSITY OF 85
KTS IS ON THE HIGH SIDE, BUT CONSISTENT WITH, PGTW AND KNES DVORAK
CURRENT INTENSITY ESTIMATES OF T4.5 (77 KTS). THE UPPER-LEVEL
ENVIRONMENT IS UNFAVORABLE OVERALL WITH STRONG (20-25 KT) VERTICAL
WIND SHEAR (VWS) BEING PARTIALLY OFFSET BY A STRONG POLEWARD OUTFLOW
CHANNEL. SEA SURFACE TEMPERATURE IS MARGINALLY SUPPORTIVE AT 26-27
CELSIUS. FOR THE DURATION OF THE FORECAST, TC 19S WILL TRACK ALONG
THE NORTHWESTERN PERIPHERY OF A SUBTROPICAL RIDGE. THE HOSTILE
ENVIRONMENT WILL PERSIST AND CAUSE STEADY WEAKENING UNTIL
DISSIPATION, EXPECTED BETWEEN TAU 96 AND TAU 120. THE JTWC TRACK
FORECAST CLOSELY FOLLOWS CONSENSUS, IN LINE WITH THE BULK OF THE
MODEL GUIDANCE. HOWEVER, THERE ARE EQUATORWARD (GALWEM AND UKMET)
AND POLEWARD (NAVGEM) OUTLIERS THAT MAKE THE CROSS-TRACK SPREAD
ABOUT 370 NM BY TAU 120. OF THE MEMBERS THAT FOLLOW A SIMILAR TRACK
TO THE JTWC TRACK FORECAST, THERE IS SUBSTANTIAL VARIATION IN ALONG-
TRACK SPEED. FOR THOSE REASONS, THERE IS LOW CONFIDENCE IN THE JTWC
TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 180000Z IS 30
FEET. NEXT WARNINGS AT 180900Z, 181500Z, 182100Z AND 190300Z.//
NNNN

WARNING 17/JTWC
WARNING 17/JTWC

WARNING 17/JTWC
WARNING 17/JTWC

0430UTC
0430UTC

2351UTC
2351UTC


HWRF AT 18UTC: 93KT AT +30H
HWRF AT 18UTC: 93KT AT +30H

GFS AT 18UTC: 80KT AT +0H
GFS AT 18UTC: 80KT AT +0H


Rédigé par PATRICK HOAREAU le Lundi 18 Mars 2019 à 09:22