South China Sea cyclone may launch monsoon into Bay

Global models indicate the possibility of a South China Sea cyclone helping launch the southwest monsoon into the Andaman and Nicobar Islands, its first port of call in the Indian territorial waters, around the normal date.

This is even as India Meteorological Department (IMD) has been keeping a watch for the first pre-monsoon low-pressure area to spring up in the Bay of Bengal. But a core of strong westerlies already blowing across the plains and into the Bay of Bengal may put paid to these hopes.

A fresh western disturbance is expected to check into western Himalayas and northwest India by Thursday and opposing flows from this may snuff out any chance of revival of full-fledged ‘low' in the Bay.

A weak circulation would likely be all that is left of the current churn in the Bay, which would be made to retreat east-northeast towards the Myanmar coast.

The IMD has withdrawn its watch for the “low” effective from the afternoon bulletin on Monday. It is in this backdrop that the forecast about the likely formation of a cyclone in the South China Sea by the European Centre for Medium-Range Weather Forecasts (ECMWF) assumes significance.

The “wet season” has already unfolded over Southeast Asia from Sunday (May 1), regional met agencies confirmed.

This is the usual date for the onset here and the winds would turn southwesterly as a “low” originating in the west Pacific crosses the Philippines and drifts into adjoining South China Sea.

The ECMWF expects this system to drop anchor here, and grow in strength to become a tropical cyclone by May 12, up to which its guidance is available. The US National Centres for Environmental Prediction expects this system to hurl a potent circulation into the Andaman Sea, or extreme southeast Bay of Bengal, during the week that follows.

This could also bring the southwest monsoon into Andaman and Nicobar region around the normal time for onset (May 15 to 20). It will take another fortnight for the Arabian Sea arm of the monsoon to make a splash over the Kerala coast