BOB 05/2010/21
Time of issue: 0530 hours IST
Dated: 07.11. 2010
Orange
Message
Sub: Severe Cyclonic Storm ‘JAL’ over Southwest Bay of Bengal: Cyclone
Warning for North Tamil Nadu and South Andhra Pradesh Coasts
The Severe cyclonic storm, ‘JAL’ remained practically stationary and lay
centered at 0230 hrs IST of today, the 7th November 2010, over southwest Bay of Bengal
near lat.11.00N and long. 84.00E about 400 km northeast of Trincomalee (Sri Lanka), 450
km southeast of Chennai and 600 km southeast of Nellore. It would intensify further, move
west-northwestwards and cross north Tamil Nadu and south Andhra Pradesh coasts
between Puducherry and Nellore close to Chennai by today, the 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)
07-11-2010/0230
07-11-2010/0830
07-11-2010/1430
07-11-2010/2030
08-11-2010/0230
08-11-2010/1430
09-11-2010/0230
09-11-2010/1430
Position
(lat. 0N/ long. 0E)
11.0/84.0
11.5/83.5
12.5/82.5
13.0/81.5
13.5/80.0
14.0/79.0
15.0/77.5
16.5/75.5
Sustained maximum surface
wind speed (kmph)
110-120 gusting 130
120-130 gusting 140
120-130 gusting 140
120-130 gusting 140
120-130 gusting 140
110-120 gusting 130
50-60 gusting 70
35-45 gusting 55
Intensity
Severe Cyclonic Storm
Very Severe Cyclonic Storm
Very Severe Cyclonic Storm
Very Severe Cyclonic Storm
Very Severe Cyclonic Storm
Severe Cyclonic Storm
Deep Depression
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 12 hours and 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. Fairly
widespread rain with isolated heavy to very heavy falls would occur over south coastal
Tamilnadu during next 48 hours.
Gale winds speed reaching 60-70 kmph gusting to 80 kmph would prevail along
and off North Tamil Nadu, Puducherry and south Andhra Pradesh coasts during next 12
hours. 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 of Tamilnadu 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.
The system is under constant surveillance and concerned state Govts. are being informed.
REMARKS
VERTICAL WIND SHEAR OF HORIZONTAL WIND OVER THE REGION IS MODERATE TO
HIGH (20-30 KTS). 24 HOUR TENDENCY OF VERTICAL WIND SHEAR IS NEGATIVE (-5 KNOTS) OVER
PARTS OF SOUTHWEST BAY OF BENGAL AND (-5 TO -10 KNOTS) OVER EASTCENTRAL BAY OF
BENGAL. SEA SURFACE TEMPERATURE IS 290-310 C AND THE OCEAN HEAT CONTENT OVER
SOUTH WEST BAY OF BENGAL 80-90 KJ/CM2.. THE RELATIVE VORTICITY AT 850 HPA LEVEL IS
(15-20×10-5S-1) AND UPPER LEVEL DIVERGENCE (10-20) AROUND THE SYSTEM CENTRE IS
FAVOURABLE FOR INTENSIFICATION. THE SYSTEM LIES TO THE SOUTH OF TROPOSPHERIC
RIDGE, WHICH ROUGHLY RUNS ALONG 170N AT 200 HPA LEVEL.
Next bulletin will be issued at 0830 hrs IST of 7th November.