TC 22S(HEROLD): has commenced subtropical transition



TC 22S. 0830UTC ANIMATION

CIRA
CIRA
TC 22S(HEROLD) SOUTH INDIAN
As of 06:00 UTC Mar 18, 2020:
Location: 22.7°S 66.1°E
Maximum Winds: 55 kt( 100km/h)
Gusts: 70 kt ( 130km/h)
Minimum Central Pressure: 992 mb

REMARKS:
180900Z POSITION NEAR 23.0S 66.7E.
18MAR20. TROPICAL CYCLONE (TC) 22S (HEROLD), LOCATED APPROXIMATELY
516 NM EAST-SOUTHEAST OF PORT LOUIS, MAURITIUS, HAS TRACKED
SOUTHEASTWARD AT 14 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY DEPICTS A FULLY-EXPOSED LOW-LEVEL
CIRCULATION WITH DEEP CONVECTION SHEARED ABOUT 48NM TO THE SOUTHEAST
DUE TO STRONG NORTH-NORTHWESTERLY VERTICAL WIND SHEAR (25 TO 30
KNOTS). THE INITIAL INTENSITY IS ASSESSED AT 55 KNOTS BASED ON AN
180521Z ASCAT-B IMAGE, WHICH SHOWS 50-55 KNOT WINDS OVER THE WESTERN
QUADRANT. THE INITIAL WIND RADII HAVE BEEN ADJUSTED BASED ON THE
BULLSEYE ASCAT-B IMAGE. TC 22S IS FORECAST TO TRACK EAST-
SOUTHEASTWARD THROUGH THE FORECAST PERIOD ALONG THE SOUTHERN
PERIPHERY OF A DEEP-LAYERED STEERING RIDGE POSITIONED TO THE NORTH.
OVERALL, TRACK UNCERTAINTY REMAINS LOW WITH A TIGHT CLUSTER OF
NUMERICAL MODEL AND ECMWF ENSEMBLE TRACK GUIDANCE THROUGH TAU 24. TC
22S WILL CONTINUE TO WEAKEN STEADILY AS IT CONTINUES TO INTERACT
WITH THE SUBTROPICAL WESTERLIES AND ENCOUNTERS INCREASING VERTICAL
WIND SHEAR (25 TO 30 KNOTS). THE SYSTEM HAS COMMENCED SUBTROPICAL
TRANSITION (STT) AND SHOULD COMPLETE STT BY TAU 24 AS IT BECOMES
EMBEDDED WITHIN THE STRONG SUBTROPICAL WESTERLY FLOW. DUE TO THE
HOSTILE ENVIRONMENT AND RAPID WEAKENING, THERE IS SOME POTENTIAL FOR
THE SYSTEM TO DISSIPATE PRIOR TO COMPLETING STT. MAXIMUM SIGNIFICANT
WAVE HEIGHT AT 180600Z IS 23 FEET. NEXT WARNINGS AT 182100Z.//
NNNN
 

TC 22S: WARNING 11: HAS COMMENCED SUPBTROPICAL TRANSITION

JTWC
JTWC

FORECAST TRACK AND INTENSITY GUIDANCE

CIRA
CIRA


18/0521UTC

FNMOC
FNMOC


18/0121UTC

FNMOC
FNMOC

 

18/0545UTC

JTWC
JTWC

18/00UTC

FNMOC
FNMOC
Rédigé par PATRICK HOAREAU le Mercredi 18 Mars 2020 à 12:45