Date:30/11/2005 URL: http://www.thehindubusinessline.com/2005/11/30/stories/2005113001951900.htm

Back `Cyclone Baaz' headed for landfall on TN-AP coasts

Vinson Kurian

The city of Chennai and areas to the immediate north will possibly bear the brunt as the storm barrels into the peninsular coast.

Thiruvananthapuram , Nov. 29

MONDAY'S depression over southeast Bay of Bengal intensified into a cyclonic storm overnight and sped coastward in a west-northwest direction at a reasonably fast 17 km/h to lie centred about 600 km east-southeast of Chennai on Tuesday afternoon.

Named `Baaz' (the season's second such but numbered till the previous day as 05 B), the storm is heading for a landfall on the north Tamil Nadu/south coastal Andhra Pradesh coasts by early Thursday morning, according to nearly consensus predictions by various weather models.

The Honolulu-based Joint Typhoon Warning Centre (JTWC) has said that full-scale intensification of the storm is unlikely to happen since the storm is predicted to run into moderate vertical wind shear over the southwest Bay. At their lowest values, vertical wind shear aids intensification of the storm centred off the coast at a given time.

The National Centres for Environmental Prediction (NCEP) of the US says the outer rain bands of the massive storm will start probing coastal Tamil Nadu areas in less than 24 hours triggering scattered rainfall.

The New Delhi-based National Centre for Medium Range Weather Forecasting (NCMRWF) is more or less in agreement with this outlook.

Sea surface temperatures hold still above the threshold levels, which could be one reason why most models bet on the system intensifying moderately over a 36 to 48-hour period by when it would have crossed land.

The city of Chennai (13.5N) and areas to the immediate north will possibly bear the brunt as the storm barrels into the peninsular coast with maximum sustained winds reaching 50 knots (92 km/h) gusting to 70 knots (130 km/h) as per JTWC forecasts.

The 48-hour extended outlook of JTWC sees wind speeds topping even 60 knots (111 km/h) with gusts of 75 knots (139 km/h) as the storm struts its stuff over south coastal Andhra Pradesh (14.4N and 80.9E). The UK Met Office forecast expects the storm to wind down to below tropical storm strength by Saturday (December 3).

Significantly, at least one model (that of the NCEP) sees a new cyclonic circulation taking shape over extreme southeast Bay by Friday. It is tipped to strengthen within the subsequent 24 hours, move further west-northwest into south central Bay possibly as a `low.'

By Monday, the latest day for which forecasts are available, the system will have grown in strength to head coastward hot on the heels of Cyclone Baaz.

Meanwhile, in its forecast, the NCMRWF said the cyclonic storm over Bay would see the rain belt move progressively from coastal Tamil Nadu, Pondicherry and south coastal Andhra Pradesh into interior peninsula over the next few days dumping fairly widespread to widespread rain with heavy to very heavy falls at a few places.

The `low' over the central parts of south Arabian Sea persisted on Tuesday as well. Predictions suggest its continued presence even as it keeps moving to the west over the next two days. Rainfall over Lakshadweep is seen tapering off in tandem with this movement of the system.

Both the Bay and Arabian Sea systems will remain part of the east-west shear zone that is seen persisting for another 4-5 days.