‘Low’ pops up over South-East Bay, may intensify

India Meteorological Department (IMD) has traced a low-pressure over South-East Bay of Bengal and adjoining south Andaman Sea on Tuesday.

The system is likely to become more marked, the IMD outlook said. It may persist during the next three days with a movement to west-north-west – towards the Sri Lankan coast.

The cyclonic circulation tracking model, NGP, by the US National Centrefor Environmental Prediction agreed with this outlook positing the system for a landfall over Sri Lanka and adjoining South-East Tamil Nadu coast by November 30.

CONVECTIVE CLOUDS


But the Canadian Meteorological Centre took the system to a more north-north-west track that would take it to central Tamil Nadu coast during the same time span.

Satellite imagery showed convective clouds over parts of south Bay of Bengal and South-East Arabian Sea. The IMD has forecast isolated to scattered rainfall over extreme south peninsular India during until the weekend.

The Chennai Regional Meteorological Centre said that rainfall occurred at a few places over Tamil Nadu. Isolated rainfall occurred over Karnataka, Kerala, coastal Andhra Pradesh and Rayalaseema.

The North-East monsoon was subdued during the past 24 hours ending Tuesday morning as a dry phase of the Madden-Julian Oscillation (MJO) wave began impacting equatorial Indian Ocean and neighbourhood.

But, easterlies still continue to make their presence felt over the Bay of Bengal, more so, to the east and south-east. There is a low-pressure area upstream in the South China Sea as well, sustaining the flows into the Bay.

Tuesday’s ‘low’ over south-east Bay of Bengal would be able to relay in the moisture-laden easterlies further to the west.

In this manner, the scattered to isolated rainfall regime over south peninsular India should hold until the weekend.

Meanwhile, the European Centre for Medium-Range Weather Forecasts (ECMWF) sees the possibility of a busy South China Sea pushing in a fresh circulation into the Bay by the weekend.

It is tipped to keep moving to the west in the Bay basin until December 4 by when it would have washed ashore over the Tamil Nadu coast. It would set off a basin-wide trough that could cover east and south-east Arabian Sea as well.

RAIN FORECAST


Forecast by the Chennai Met Centre for the next two days said that rain or thundershowers are likely to occur at a few places over Tamil Nadu, Puducherry, coastal Karnataka, Kerala and Lakshadweep.

Isolated rain or thundershowers are likely to occur over Rayalaseema, coastal Andhra Pradesh and south interior Karnataka.

Towards the north, a feeble western disturbance is affecting the western Himalayan region. Cold wave conditions prevailed in some parts of Himachal Pradesh.

Isolated rain or snow has been forecast over the region during the next two days.

Maximum temperatures are below normal over parts of Madhya Pradesh, north Chhattisgarh and Jharkhand.