Tamil Nadu Weather Alert: Heavy to Very Heavy Rain Likely Until October 26, Chennai May Get Thunderstorms

The Regional Meteorological Centre (RMC) has forecast continued heavy to very heavy rainfall across parts of Tamil Nadu, Puducherry and Karaikal until October 26, 2026, as two weather systems develop over the Bay of Bengal. Chennai may experience moderate rainfall, thunderstorms and lightning in some areas on Thursday.

A low-pressure area is likely to form over the Southwest Bay of Bengal and the adjoining Tamil Nadu coast on Wednesday, bringing further rainfall to several districts. The India Meteorological Department (IMD) has also warned of thunderstorms, lightning and gusty winds in parts of the state.

Two Weather Systems to Bring More Rain to Tamil Nadu

A trough associated with a cyclonic circulation over the Southwest Bay of Bengal, off the north Tamil Nadu coast, extends towards north coastal Andhra Pradesh at an altitude of around 3.1 km above mean sea level.

Meanwhile, another upper-air cyclonic circulation over the Gulf of Thailand and adjoining Thailand and Myanmar is expected to move into the north Andaman Sea by Wednesday morning.

Under its influence, a fresh low-pressure area is likely to develop over the Southeast Bay of Bengal around October 23. The system is expected to move northwestwards and may intensify, influencing rainfall activity across Tamil Nadu.

Heavy Rainfall Alert for Tamil Nadu Districts

On Wednesday, heavy to very heavy rainfall accompanied by thunderstorms, lightning and gusty winds of 40–50 kmph is likely at isolated places in the following districts:

- Thoothukudi

- Tirunelveli

- Kanniyakumari

On Thursday, heavy to very heavy rainfall is expected to continue in Tenkasi, Virudhunagar and Ramanathapuram districts.

Heavy rain, thunderstorms and lightning are also likely at one or two places in the Nilgiris, Coimbatore, Erode, Tiruppur, Namakkal, Karur, Theni, Dindigul, Tenkasi, Madurai, Virudhunagar, Pudukkottai, Thanjavur, Tiruvarur, Nagapattinam, Mayiladuthurai, Sivagangai and Ramanathapuram districts, as well as Karaikal.

Chennai Weather Forecast

Chennai is likely to experience moderate rainfall, thunderstorms and lightning in some areas on Thursday. On Wednesday, the maximum temperature is expected to be around 30°C, while the minimum temperature may be approximately 25°C.

Residents should remain cautious during thunderstorms, avoid exposed areas during lightning and follow official weather advisories.

Rainfall Forecast Until October 26

According to the IMD, widespread rainfall is likely over Tamil Nadu, Puducherry and Karaikal over the next couple of days, followed by isolated to scattered rainfall between October 23 and October 26.

Residents in rain-prone districts are advised to monitor official weather updates and take precauautions against waterlogging, strong winds and lightning.