Cyclone "Mahasen" - Moved N-W, slight weakening witnessed.

Analysis show a slight weakening during past 6 hrs.
Moved N-W. According to JTWC, the system should slow down and move N-N-E in next 12 hrs.
Pressure now is around 989 mb.
Winds gusting up to 85 kmph.

JTWC warning and Path projection at 2:30pm IST
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TROPICAL CYCLONE 01B (MAHASEN), LOCATED APPROXIMATELY 760 NM SOUTH 
OF CALCUTTA, INDIA, HAS TRACKED NORTHWESTWARD AT 12 KNOTS OVER THE 
PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) 
REVEALS FLARING DEEP CENTRAL CONVECTION WITH FRAGMENTED CONVECTIVE 
BANDING WRAPPING INTO A CONSOLIDATING LOW-LEVEL CIRCULATION CENTER 
(LLCC) WITH SEVERAL LARGE OUTFLOW BOUNDARIES APPARENT IN THE EASTERN 
AND SOUTHERN SEMI-CIRCLES. THIS IS ALSO APPARENT IN A 120342Z AMSU-B 
MICROWAVE IMAGE. THE PAST FEW MICROWAVE IMAGES HAVE SHOWN A RE-
CONSOLIDATION OF THE LLCC FURTHER EAST OF THE PREVIOUS POSITION AND 
HAVE ADDITIONALLY SHOWN DRY CONTINENTAL AIR IS BEING INGESTED FROM 
THE COAST OF INDIA. THIS CAN ALSO BE SEEN IN THE LATEST MICROWAVE 
DERIVED TOTAL PRECIPITABLE WATER LOOP. OBSERVATIONS IN KOLKATA, 
INDIA SHOW A LARGE DEW POINT SPREAD OF 20 DEGREES. THIS DRY AIR 
INGESTION IS REASON FOR THE FRAGMENTED AND FLARING NATURE OF THE 
SYSTEM OVER THE LAST 12 HOURS. THE INITIAL POSITION IS BASED UPON 
THE MSI LOOP AND EXTRAPOLATION FROM THE 120342Z AMSU IMAGE WITH LOW 
CONFIDENCE. THE INITIAL INTENSITY HAS BEEN SLIGHTLY LOWERED TO 45 
KNOTS BASED ON LOWER DVORAK INTENSITY ESTIMATES FROM ALL AGENCIES 
AND THE OVERALL CONVECTIVE ORGANIZATION OF THE SYSTEM. UPPER-LEVEL 
ANALYSIS REVEALS A FAVORABLE ENVIRONMENT OF STRONG DIFFLUENCE ALOFT 
PROVIDING FAVORABLE OUTFLOW AND LOW TO MODERATE VERTICAL WIND SHEAR 
(VWS), WHICH IS BEING OFFSET BY THE STORM MOTION, RESULTING IN AN 
OVERALL LOW VWS (05-10 KNOTS) ENVIRONMENT. TC 01B IS FORECAST TO 
CONTINUE NORTHWESTWARD FOR THE NEXT 12 HOURS ALONG THE SOUTHWESTERN 
PERIPHERY OF THE SUBTROPICAL RIDGE (STR) SITUATED OVER THE NORTHERN 
ANDAMAN SEA. AFTER TAU 12, IT IS EXPECTED TO SLOW DOWN BEFORE IT 
TURNS NORTHEASTWARD AS THE STR WEAKENS AND RE-ORIENTS IN RESPONSE TO 
AN APPROACHING MID-LATITUDE SHORTWAVE TROUGH CURRENTLY OVER NORTHERN 
INDIA. TC 01B WILL CONTINUE TO INTENSIFY TO A PEAK OF 80 KNOTS BY 
TAU 72 AS THE SYSTEM CROSSES THE RIDGE AXIS INTO AN AREA OF 
INCREASED POLEWARD OUTFLOW, WITH ITS EXPOSURE INTO THE STRONG 
WESTERLIES. AFTER TAU 96, THE SYSTEM WILL MAKE LANDFALL NEAR 
CHITTAGONG, BANGLADESH, AS A SIGNIFICANT CYCLONE ALL WHILE WEAKENING 
DUE TO THE LAND INTERACTION. DYNAMIC MODEL GUIDANCE HAS DEVELOPED A 
BIFURCATION IN THE LATEST RUN AS GFDN AND NAVGEM HAVE GREATLY 
DEVIATED TO THE NORTHWEST INTO NORTHEASTERN INDIA. THIS IS BELIEVED 
TO BE DUE TO THE MODEL TRACKERS ERRONEOUSLY TRACKING INTO THE 
PREVIOUSLY MENTIONED SHORTWAVE TROUGH. GFS, ECMWF AND EGRR HAVE 
STAYED CONSISTENT WITH THE RECURVE SCENARIO INTO BANGLADESH. DUE TO 
THIS, THE JTWC FORECAST IS FASTER AND EAST OF MULTI-MODEL CONSENSUS 
TO OFFSET THE NAVGEM AND GFDN SOLUTIONS AND IS CONSISTENT WITH THE 
PREVIOUS FORECAST. DUE TO LARGE SPREAD IN THE MODEL SOLUTIONS AND 
AMBIGUITY IN THE INITIAL POSITION FORECAST CONFIDENCE IS LOW. 
JUSTIFICATION FOR RELOCATION: RELOCATED 12/00Z POSITION OF TC 01B 
BASED ON NEWLY AVAILABLE MICROWAVE DATA. MAXIMUM SIGNIFICANT WAVE 
HEIGHT AT 120600Z IS 18 FEET.

IMD Warning at 1pm

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The cyclonic storm MAHASEN over southeast Bay of Bengal moved slightly
westwards at a speed of 15kmph and lay centred at 1130 hrs IST of 12th May 2013 near latitude 10.00 N and longitude 87.00 E, about 650 km west-northwest of Car Nicobar, 650 km east-northeast of Trincomalee, 800 km southeast of Chennai and 1440 km south-southwest of Chittagong. It would move initially northwestwards during next 36 hours and recurve thereafter northeastwards towards Bangladesh-Myanmar coast.

Latest NAVGEM (NOGAPS) model expects a N-E Andhra and S.Odisha coast landfall on 16-May.