Tamil Nadu is bracing for a sustained spell of heavy rain as the northeast monsoon enters an active phase, with the India Meteorological Department forecasting isolated heavy falls across the state and flagging a fresh weather system over the Bay of Bengal that could strengthen into a cyclone.
The IMD has forecast isolated heavy rainfall over Tamil Nadu, Puducherry and Karaikal on November 10 and 11, and again on November 15 and 16. The Regional Meteorological Centre in Chennai has warned of heavy rain with thunderstorms, lightning and strong winds in Ramanathapuram and Thoothukudi districts, with moderate rain expected across a broad swath of districts from Thanjavur and Tiruvannamalai to Kanyakumari.
The rain so far has been intense in the south. Kayalpattinam in Thoothukudi district recorded 11 cm of rainfall in the 24 hours ending at 8.30 am on November 9, the highest in the state. The downpour is driven by an upper-air cyclonic circulation over the Comorin area, which is keeping the southern and delta districts wet through November 12.
The season’s tally is already above normal. Tamil Nadu and Puducherry have received 25.4 cm of rain between October 1 and November 9, against a climatological normal of 24.3 cm — about four per cent above average — as the northeast monsoon delivers persistent moisture across the southern peninsula.
Attention is now shifting to the Bay of Bengal. The IMD expects a fresh low-pressure area to form over the southeast Bay around November 13, becoming a well-marked low within 24 hours. Weather officials say the system could gradually intensify and move towards Sri Lanka by November 15, with a possible approach to the Tamil Nadu coast around November 19.
Forecasters are careful to stress the uncertainty. Not all low-pressure areas become cyclones, and the system’s strength, track and landfall — if any — will depend on how it evolves over the next few days. Models currently indicate a low probability of intensification into a depression, but a second widespread spell of rain for Tamil Nadu between November 15 and 20 is on the cards if the system strengthens.
The forecast comes weeks after Cyclones Arnab and Murasu battered the Andhra Pradesh and Odisha coasts. A western disturbance is also expected to bring rain and snowfall to the Western Himalayas through November 13, with isolated heavy rain and snow over the Kashmir Valley on November 12.
For Tamil Nadu, the advice is familiar: watch the IMD bulletins, avoid waterlogged stretches, and keep an eye on the Bay. The monsoon is active, and the sea is stirring again.
