Tamil Nadu, Puducherry and a few places in Kerala will receive heavy rains from December 1 following the formation of a low pressure area southeast Bay of Bengal and adjoining equatorial Indian Ocean.

“A low pressure area has formed in Bay of Bengal. This is set to intensify into a depression and bring rainfall in the next 24 hours,” said S. Balachandran director, Area Cyclone Warning Centre of the Regional Meteorological Centre, Chennai.

“There was a drop in temperature at a few places over Tamil Nadu. Chennai recorded a maximum temperature of 30.8 and 30.2 degrees Celsius at Meenambakkam and Nungambkkam respectively. Several parts of Tamil Nadu, including Chennai, will receive good rains. Fairly widespread, moderate to heavy showers are likely to occur over the entire State till December 2. Though the origin of the present weather system is in southeast Bay of Bengal, as in the case last year, this system is not as intense as it was last year. Hence, flooding is ruled out as of now but some areas may face problem of water logging,” the Skymet report said.

“Chennai has been rain deficit in November, which also happens to be the rainiest month for the city. So far, the State capital recorded a mere 50.2 mm of rain, compared to the November average rainfall of 407 mm. Now, with rains in the offing, we expect the deficiency to improve up to some extent but November will end on a deficit note,” the report added.

The minimum temperatures were 19.7 and 21 degrees Celsius at the two centres. They have dropped up to 2.4 degrees Celsius from the normal temperature during these days.

According to Skymet forecast, the low pressure area over southeast bay of Bengal is likely to intensify into a depression any time soon. The cyclonic circulation over southeast Bangladesh and neighbouring areas also prevails. In the last 24 hours, fairly widespread light to moderate rain has occurred over Andaman and Nicobar Islands.

“The sky will remain partly cloudy over Tamil Nadu, including Chennai, Kerala and coastal Andhra Pradesh. Rain and thundershowers will start making an appearance over the city from Wednesday evening but it may not be intense. By December 1, rainfall will intensify significantly,” the report said.