Posted by JAC on 4/15/2009, 1:12 pm

BOB 01/2009/07 Dated: 15th April 2009 Time of issue: 2000hours IST Sub: Cyclonic storm, ‘Bijli’ over west central Bay of Bengal : Cyclone alert The deep depression over central & adjoining southeast Bay of Bengal moved northwestwards, further intensified into a cyclonic storm, ‘Bijli’ and lay centred at 1730 hours IST of today, the 15th April 2009 near lat. 15.00 N and long. 86.50 E, about 470 km southeast of Visakhapatnam, 750 km west-northwest of Port Blair and 900 km southwest of Pathein (Myanmar). The system is likely to intensify further and move in a north-northwesterly direction for some more time. 151500Z POSITION NEAR 15.7N 85.6E. TROPICAL CYCLONE (TC) 01B LOCATED APPROXIMATELY 200 NM SOUTHEAST OF VISAKHAPATNAM, INDIA, HAS TRACKED NORTHWESTWARD AT 10 KNOTS OVER THE LAST 06 HOURS. RECENT ANIMATED MULTISPECTRAL IMAGERY AND A 151311Z SSMI/S IMAGE DEPICT AN ORGANIZED LOW LEVEL CIRCULATION CENTER (LLCC) WITH DEEP CONVECTION AROUND THE LLCC AND FRAGMENTED CONVECTIVE BANDING AROUND THE PERIPHERY. THE SYSTEM IS CURRENTLY TRACKING TO THE NORTHWEST UNDER THE INFLUENCE OF A MID TO LOW-LEVEL RIDGE LOCATED OVER ASIA MINOR. AFTER TAU 12 THE SYSTEM IS EXPECTED TO SLOW AND RECURVE AS IT APPROACHES A MID-LEVEL ANTICYCLONE OVER NORTHERN INDIA THAT WILL HELP TO TRACK THE SYSTEM TO THE EAST-NORTHEAST. NUMERICAL GUIDANCE IS GENERALLY IN GOOD AGREEMENT WITH THE MAIN CONCENTRATION OF AIDS AGREEING WITH THIS FORECAST AND THE OUTLIER EGRR INDICATING A STRAIGHT TRACK INTO THE INDIAN MAINLAND. UPPER LEVEL ANALYSIS INDICATES THAT THE SYSTEM IS UNDER THE UPPER-LEVEL RIDGE AXIS AND IN AN AREA OF LOW VERTICAL WIND SHEAR. THE SYSTEM IS EXHIBITING GOOD EQUATORWARD OUTFLOW BUT THE POLEWARD OUTFLOW CHANNEL HAS BEEN SUPPRESSED DUE TO CONVERGENCE ALOFT AND WIDESPREAD SUBSIDENCE TO THE NORTH OF THE SYSTEM. INTENSITY GUIDANCE HAS BEEN STEADILY BACKING OFF OVER THE LAST 12 HOURS. FORECAST INTENSITY IS LOWER THAN GUIDANCE AS INTENSIFICATION IS NOT EXPECTED AFTER THE SYSTEM COMPLETES RECURVATURE AND BEGINS ACCELERATING INTO THE BAROCLINIC ZONE. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 151200Z IS 14 FEET. NEXT WARNINGS AT 160300Z AND 161500Z.