Monday, May 13, 2013

Cyclone "Mahasen" - Slowly moved North, intensified slightly!

Analysis show that the cyclone has moved slowly to the North as expected by most of the weather models.
Latest position is 11.8N , 86.7E
Pressure has decreased again to 985 mb
Winds gusting up to 93 kmph

11am, Satellite IR shows good convective activity and well maintained core. Most of South Peninsular India is cloudy due to over night rain and due to Mahasen's outer bands.

JTWC warning and projected path at 8:30am IST
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

TROPICAL CYCLONE 01B (MAHASEN), LOCATED APPROXIMATELY 673 NM
SOUTHWARD OF CALCUTTA, INDIA, HAS TRACKED NORTHWARD AT 08 KNOTS
OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY
SHOWS THE CENTRAL DENSE OVERCAST FEATURE THAT IS OBSCURING THE LOW
LEVEL CIRCULATION CENTER (LLCC) HAS CONTRACTED BUT SLIGHTLY DEEPENED.
THE INITIAL POSITION IS BASED ON RECENT MICROWAVE SATELLITE IMAGES
INCLUDING A 122345Z SSMI/S PASS THAT SHOW THE LLCC EAST OF THE MAIN
CONVECTION. THE INITIAL INTENSITY IS BASED ON THE HIGH END OF DVORAK
ESTIMATES FROM PGTW AND KNES. UPPER LEVEL ANALYSIS INDICATES THE
SYSTEM IS 06 DEGREES SOUTH OF THE RIDGE AXIS IN AN AREA OF MODERATE
(20 KNOT) EASTERLY VERTICAL WIND SHEAR (VWS); HOWEVER, THE VWS IS
OFFSET BY ROBUST WESTWARD OUTFLOW, AS EVIDENCED ON ANIMATED WATER
VAPOR IMAGERY. THE CYCLONE IS NOW ROUNDING THE WESTERN EDGE OF THE
SUBTROPICAL RIDGE TO THE EAST. IT IS EXPECTED TO SLOW DOWN OVER THE
NEXT 12 HOURS AS IT MAKES THE TURN BEFORE RECURVING NORTHEASTWARD ON
THE POLEWARD SIDE OF THE RIDGE AXIS. TC 01B WILL GRADUALLY INTENSIFY
AS THE VWS RELAXES ALONG THE RIDGE AXIS. ADDITIONALLY, THE POLEWARD
OUTFLOW IS EXPECTED TO OPEN UP AS THE SYSTEM BECOMES EXPOSED TO THE
PREVAILING WESTERLIES. AFTER TAU 72, TC MAHASEN WILL GRADUALLY WEAKEN
AS VWS INCREASES BEFORE MAKING LANDFALL NEAR CHITTAGONG, BANGLADESH.
LAND INTERACTION WILL RAPIDLY ERODE AND DISSIPATE THE SYSTEM BEFORE
THE END OF THE FORECAST. THE AVAILABLE NUMERICAL GUIDANCE IS IN
AGREEMENT WITH THE RECURVE SCENARIO WITH THE EXCEPTION OF NAVGEMS AND
GFDN THAT OFFER A CONTINUED NORTHWARD PROGRESSION. THE JTWC FORECAST
IS LAID CLOSE TO MODEL CONSENSUS WITH POOR CONFIDENCE IN VIEW OF THE
LARGE VARIANCES IN THE MODEL MEMBERS.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 130000Z IS 18 FEET

Latest COLA GFS model suggests that the cyclone will continue to move North for another 24hrs and then N-E towards Bangladesh. Landfall expected over S.Bangladesh on 16-May.

No comments:

Post a Comment