Saturday, November 06, 2010
Update on Cyclone Jal ... Upgraded to category 1 and moved N-W
Wind :: 120 kmph
Pressure :: 974 mb
Though it had moved in N-W direction, the upper air current is still favorable for a N. Tamilnadu landfall.
IMD warning, 8:30am IST
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JTWC warning
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060300Z POSITION NEAR 10.7N 85.5E. TROPICAL CYCLONE (TC) 05B (JAL), LOCATED APPROXIMATELY 370 NM EAST-SOUTHEAST OF CHENNAI, INDIA, HAS TRACKED NORTHWESTWARD AT 07 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY AND A 060019Z 91H SSMIS MICROWAVE IMAGE DEPICT TIGHTLY CURVED LOW LEVEL BANDING WITH DEEPENING CENTRAL CONVECTION. THERE IS GOOD CONFIDENCE IN THE CURRENT POSITION BASED ON A MICROWAVE EYE FEATURE IN THE 060019Z 37H SSMIS MICROWAVE PASS. THE CURRENT INTENSITY IS BASED ON DVORAK ESTIMATES RANGING FROM 45 TO 65 KNOTS FROM DEMS, KNES, AND PGTW. UPPER LEVEL ANALYSIS INDICATES THE SYSTEM IS EXPERIENCING SOME PRESSURE ALONG THE EASTERN PERIPHERY DUE TO MODERATE (20-25 KNOTS) EASTERLY VERTICAL WIND SHEAR. HOWEVER, STRONG DIFFLUENCE ALOFT, AND GOOD OVERALL OUTFLOW IN THE WESTERN QUADRANTS, HAVE ALLOWED THE SYSTEM TO STEADILY INTENSIFY. TC JAL IS CURRENTLY TRACKING ALONG THE SOUTHERN PERIPHERY OF A MID-TO-DEEP LAYER SUBTROPICAL STEERING RIDGE AND IS EXPECTED TO CONTINUE ALONG A GENERALLY NORTHWESTWARD TRACK THROUGHOUT THE FORECAST PERIOD. TC 05B IS FORECAST TO STEADILY INTENSIFY BEFORE MAKING LANDFALL NEAR CHENNAI, INDIA JUST AFTER TAU 36. THE SYSTEM WILL WEAKEN BELOW WARNING CRITERIA (35 KNOTS) AS IT TRACKS ACROSS SOUTHERN INDIA, BUT COULD RE-INTENSIFY AS IT RE-EMERGES IN THE NORTHEASTERN ARABIAN SEA AFTER TAU 72. NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT, THEREFORE THIS FORECAST REMAINS CLOSE TO MODEL CONSENSUS AND IS CONSISTENT WITH THE PREVIOUS FORECAST.
JTWC tracking
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Satellite, 8am IST
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JAL TRACK
06112010 / 0745 hrs IST:
THE CYCLONIC STORM ‘JAL’ JAL MOVED WEST-NORTWESTWARDS, INTENSIFIED INTO SEVERE CYCLONIC STORM AND LAY CENTERED AT 2100 UTC OF 5TH NOVEMBER 2010, NEAR LAT. 10.00N AND LONG. 86.00E ABOUT 550 KM EAST-NORTHEAST OF TRINCOMALEE (43418), 700 KM EAST-SOUTHEAST OF CHENNAI (43279) AND 850 KM SOUTHEAST OF NELLORE (43245) SUSTAINED MAXIMUM SURFACE WIND SPEED IS ESTIMATED TO BE ABOUT 55 KNOTS. GUSTING TO 65 KNOTS. THE STATE OF THE SEA IS VERY HIGH AROUND THE SYSTEM CENTRE. THE ESTIMATED CENTRAL PRESSURE IS ABOUT 990 HPA.
ANIMATION OF PAST 24HRS INSAT IMAGERIES INDICATES INCREASE IN DEEP CONVECTION AND CLOUD MASS IS MORE ORGANISED. THE INTENSITY OF THE SYSTEM IS T3.5. THE CLOUD DENSE OVERCAST (CDO) WITH WELL DEFINED BANDING FEATURES. INTENSE TO VERY INTENSE CONVECTION AROUND THE SYSTEM CENTRE AND BROKEN INTENSE TO VERY INTENSE CONVECTION BETWEEN LAT.6.00 TO 15.50 NORTH AND WEST OF LONG 89.00 EAST. THE LOWEST CLOUD TOP TEMPERATURE (CTT) DUE TO CONVECTION IS AROUND -800 TO -850C IN ASSOCIATION WITH THE SYSTEM.
THE CURRENT ENVIRONMENTAL CONDITIONS AND NUMERICAL WEATHER PREDICTION (NWP) MODELS SUGGEST THAT. THE SYSTEM WOULD INTENSIFY FURTHER. THE SYSTEM WOULD MOVE WEST-NORTHWESTWARDS AND CROSS NORTH TAMIL NADU AND SOUTH ANDHRA PRADESH COASTS BETWEEN PUDUCHERRY (43331) AND NELLORE (43245) CLOSE TO CHENNAI (43279) BY 7TH NOVEMBER 2010 NIGHT. BASED ON LATEST ANALYSIS WITH NWP MODELS AND OTHER CONVENTIONAL TECHNIQUES, ESTIMATED TRACK AND INTENSITY OF THE SYSTEM ARE GIVEN IN THE TABLE BELOW: JAL WATCH
Sub:Severe Cyclone ‘JAL’ over Southeast Bay of Bengal: Cyclone Warning for North Tamil Nadu and South Andhra Pradesh Coasts-Orange Message
The cyclonic storm, ‘JAL’ over southeast Bay of Bengal moved west-northwestward, intensified into Severe Cyclonic storm and lay centered at 0230 hrs IST of today, the 6th November 2010, near lat.10.00N and long. 86.00E about 550 km east northeast of Trincomalee (Sri Lanka), 700 km east-southeast of Chennai and 850 km southeast of Nellore. It would intensify further into a very severe cyclonic storm. The system would move west-northwestwards and cross north Tamil Nadu and south Andhra Pradesh coasts between Puducherry and Nellore close to Chennai by 7th November 2010 night.
Based on latest analysis with NWP models and other conventional techniques, estimated track and intensity of the system are given in the Table below:
Date/Time(IST) | Position (lat. 0N/ long. 0E) | Sustained maximum surface wind speed (kmph) | Intensity |
06-11-2010/0230 | 10.0/86.0 | 90-100 gusting 110 | Severe Cyclonic Storm |
06-11-2010/0830 | 10.5/85.5 | 100-110 gusting 120 | Severe Cyclonic Storm |
06-11-2010/1430 | 11.0/85.0 | 110-120 gusting 130 | Severe Cyclonic Storm |
06-11-2010/2030 | 11.5/84.0 | 110-120 gusting 130 | Severe Cyclonic Storm |
07-11-2010/0230 | 12.0/83.5 | 120-130 gusting 140 | Very Severe Cyclonic Storm |
07-11-2010/1430 | 13.0/82.0 | 120-130 gusting 140 | Very Severe Cyclonic Storm |
08-11-2010/0230 | 14.0/80.0 | 120-130 gusting 140 | Very Severe Cyclonic Storm |
08-11-2010/1430 | 15.0/79.0 | 50-60 gusting 70 | Deep Depression |
09-11-2010/0230 | 17.0/77.0 | 40-50 gusting 60 | Depression |
Under its influence, rain/thundershower would occur at most places with isolated heavy to very heavy falls over north coastal Tamil Nadu, Puducherry and south coastal Andhra Pradesh during next 24 hours. Thereafter the intensity would increase with heavy to very heavy falls at a few places and isolated extremely heavy falls (≥25 cm) over north Tamil Nadu, Puducherry, south coastal Andhra Pradesh and Rayalaseema .
Gale winds speed reaching 60-70 kmph gusting to 80 kmph would prevail along and off North Tamil Nadu, Puducherry and south Andhra Pradesh coast commencing from today evening It may increase upto 120-130 kmph gusting to 140 kmph at the time of landfall. Sea conditions will be very rough to high, along and off these coasts becoming phenomenal at the time of landfall.
Storm surge of about 1-2 metres above the astronomical tide may inundate the low lying areas of Nellore & Prakasam districts of Andhra pradesh and Tiruvallur, Chennai & Kanchipuram districts at the time of landfall.
Damage expected:
Extensive damage to thatched roofs and huts. Minor damage to power and communication lines due to uprooting of large avenue trees. Flooding of escape routes.
Action suggested:
Total suspension of fishing operations. Fishermen are advised not to venture into the sea. Coastal hutment dwellers to be moved to safer places. People in affected areas to remain indoors.
JAL WATCH
06/000Z
POSITION: 10.50 N / 85.90 E
[About 700km East NE of Nagapattinam]
Sustained Maximum winds: 100-110 kmph.
Under its influence, rain/thundershower would occur at most places with isolated heavy to very heavy falls over north coastal Tamil Nadu, Puducherry and south coastal Andhra Pradesh from morning of 6th November 2010. The intensity would increase with heavy to very heavy falls at a few places and isolated extremely heavy falls (≥25 cm) over north Tamil Nadu, Puducherry, south coastal Andhra Pradesh and Rayalaseema from morning of 7th November 2010.
Update on Cyclone Jal ... Getting more organized and moving N-W
Wind :: 105 kmph
Pressure :: 982 mb
IMD warning, 2am IST
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The cyclonic storm, ‘JAL’ over southeast Bay of Bengal moved nothwestward and lay centered at 2330 hrs IST of 5th November 2010, near lat.10.00N and long. 86.50E about 570 km east northeast of Trincomalee (Sri Lanka), 750 km east-southeast of Chennai and 850 km southeast of Nellore. It would intensify further into a severe cyclonic storm. The system would move west-northwestwards and cross north Tamil Nadu and south Andhra Pradesh coasts between Puducherry and Nellore close to Chennai by 7th November 2010 night.
JTWC warning, 2:30am IST
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052100Z POSITION NEAR 9.9N 86.0E. TROPICAL CYCLONE (TC) 05B (JAL), LOCATED APPROXIMATELY 410 NM EAST-SOUTHEAST OF CHENNAI, INDIA, HAS TRACKED WEST-NORTHWESTWARD AT 07 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY AND A 051500Z PARTIAL 89 GHZ AMSU MICROWAVE PASS DEPICT TIGHTLY CURVED BANDING WITH INCREASED DEEP CENTRAL CONVECTION. A 051500Z PARTIAL ASCAT PASS INDICATES A WELL-DEFINED LOW LEVEL CIRCULATION CENTER WITH STRONGER GRADIENT WINDS ALONG THE NORTHERN PERIPHERY. UPPER LEVEL ANALYSIS DEPICTS THE SYSTEM SOUTH OF THE RIDGE AXIS IN AN AREA OF LOW TO MODERATE (20 KNOTS) EASTERLY VERTICAL WIND SHEAR. THE CURRENT INTENSITY IS BASED ON DVORAK ESTIMATES RANGING FROM 45 TO 55 KNOTS FROM PGTW, KNES, AND DEMS. TC JAL IS CURRENTLY TRACKING ALONG THE SOUTHERN PERIPHERY OF A MID-TO- DEEP LAYER SUBTROPICAL STEERING RIDGE AND IS EXPECTED TO CONTINUE ALONG A GENERALLY WEST-NORTHWEST TRACK THROUGHOUT THE FORECAST PERIOD. BETWEEN TAU 36 AND TAU 48, TC 05B WILL MAKE LANDFALL JUST SOUTH OF CHENNAI, INDIA AND WEAKEN BELOW WARNING THRESHOLD CRITERIA (35 KNOTS) BY TAU 72. THERE IS A CHANCE THE SYSTEM COULD RE- INTENSIFY AS IT RE-EMERGES IN THE NORTHEASTERN ARABIAN SEA AFTER TAU 72. NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT WITH THIS FORECAST TRACK, WITH THE EXCEPTION OF GFDN, WHICH TRACKS THE SYSTEM MORE WESTWARD AND RE-INTENSIFIES TC 05B IN THE ARABIAN SEA. THIS FORECAST REMAINS CLOSE TO MODEL CONSENSUS AND IS CONSISTENT WITH THE PREVIOUS FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 051800Z IS 16 FEET.
JTWC tracking
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Satellite, IR, 2am IST
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