RMC Chennai forecasts heavy rain across Tamil Nadu till May 12
Synopsis
A Gulf of Mannar atmospheric circulation is set to unleash heavy rain across Tamil Nadu through 12 May, with the RMC alerting at least 11 districts — from the Nilgiris and Coimbatore in the west to Kanniyakumari and Nagapattinam in the south. Even Chennai is not spared, with thunderstorms expected to bring relief from the recent heat wave.
Key Takeaways
The Regional Meteorological Centre (RMC) , Chennai, has forecast widespread rainfall across Tamil Nadu till 12 May .
An atmospheric circulation over the Gulf of Mannar is driving the rain activity across the state.
At least 11 districts are on heavy rain alert, including Nilgiris , Coimbatore , Tiruppur , Erode , and Dindigul .
Southern districts including Tirunelveli , Kanniyakumari , Tenkasi , and Thoothukudi face heavy rain from Friday to Monday.
Chennai is expected to see thunderstorms and moderate rainfall, with cloudy conditions offering relief from recent heat.
Residents in low-lying areas and fishermen have been advised to exercise caution and follow official weather updates.
The Regional Meteorological Centre (RMC) in Chennai has forecast widespread rainfall across Tamil Nadu till 12 May, with heavy showers expected in several western and southern districts over the coming days. An atmospheric circulation prevailing over the Gulf of Mannar and adjoining areas is the primary trigger for the intense rain activity, according to the weather department.
Districts on Alert
The RMC has issued alerts for at least 11 districts across the state. Officials identified Nilgiris, Erode, Coimbatore, Tiruppur, and Dindigul as among the districts likely to receive heavy rainfall due to the prevailing weather system. The western districts — particularly the hilly and ghat regions — may experience intermittent spells of moderate to heavy showers accompanied by thunderstorms and gusty winds.
For the next two days, Theni, Madurai, Virudhunagar, Tenkasi, Tirunelveli, and Kanniyakumari districts are also likely to receive heavy rainfall, the department said.
Extended Forecast: Friday to Monday
In its extended outlook, the RMC indicated that from Friday to Monday, heavy rain is likely across Nilgiris, Erode, Coimbatore, Tiruppur, Dindigul, Madurai, and Theni districts. Several parts of southern Tamil Nadu are also expected to witness thunderstorm activity during this period.
The weather office further noted that Sivaganga, Pudukkottai, Thanjavur, Tiruvarur, Mayiladuthurai, Nagapattinam, Virudhunagar, Ramanathapuram, Tirunelveli, Kanniyakumari, Tenkasi, and Thoothukudi districts are likely to witness strong spells of rain between Friday and Monday — covering both the delta belt and the southern coastal districts.
Chennai and Suburban Areas
Chennai and its suburban areas are expected to experience thunderstorms accompanied by moderate rainfall at isolated places over the next few days. Cloudy conditions are likely to prevail across the city, providing some relief from the recent heat and humidity that has gripped the region.
Advisories for Residents and Fishermen
The RMC has advised residents in vulnerable and low-lying areas to remain cautious, as continuous rainfall may lead to waterlogging and traffic disruptions in certain regions. Fishermen have also been specifically cautioned to closely follow official weather updates and exercise caution during periods of intense rainfall and thunderstorms. Authorities stressed the importance of avoiding unnecessary travel in ghat and coastal zones during peak rain spells.
With the Gulf of Mannar circulation expected to sustain over the coming days, forecasters indicate that rain activity could remain elevated across the state well into next week.
Point of View
Where Gulf of Mannar circulations routinely intensify pre-monsoon showers across the western ghats and southern coast. What warrants attention is the breadth of the alert — spanning 11 districts from the hilly Nilgiris to coastal Nagapattinam — suggesting this is not a localised event but a state-wide rain system. Authorities must ensure that waterlogging-prone urban centres like Madurai and Chennai have drainage protocols in place, given that last year's pre-monsoon spells caused significant disruption in similar conditions. The fishermen advisory is especially critical, as the Gulf of Mannar coastline sees high fishing activity this time of year.
NationPress
12 May 2026
Frequently Asked Questions
Which districts in Tamil Nadu are under heavy rain alert till May 12?
At least 11 districts are on heavy rain alert, including Nilgiris, Erode, Coimbatore, Tiruppur, Dindigul, Madurai, Theni, Tirunelveli, Kanniyakumari, Tenkasi, and Thoothukudi. Delta districts such as Thanjavur, Nagapattinam, and Mayiladuthurai are also expected to receive strong spells of rain between Friday and Monday.
What is causing the heavy rainfall in Tamil Nadu?
An atmospheric circulation prevailing over the Gulf of Mannar and adjoining areas is the primary weather system driving the intense rainfall across Tamil Nadu. The RMC says this system is likely to sustain rain activity across the state till at least 12 May.
Will Chennai receive heavy rain during this period?
Chennai and its suburban areas are expected to experience thunderstorms with moderate rainfall at isolated places over the next few days. Cloudy conditions are likely to prevail, bringing some relief from recent heat and humidity, though the city is not under a heavy rain alert like the western and southern districts.
What precautions have authorities advised for residents and fishermen?
The RMC has advised residents in low-lying and vulnerable areas to remain cautious, as continuous rain may cause waterlogging and traffic disruptions. Fishermen have been specifically warned to follow official weather updates closely and avoid venturing out during intense rainfall and thunderstorm spells.
What is the extended weather forecast for Tamil Nadu from Friday to Monday?
From Friday to Monday, heavy rain is expected in Nilgiris, Erode, Coimbatore, Tiruppur, Dindigul, Madurai, and Theni. Delta and southern coastal districts including Sivaganga, Pudukkottai, Thanjavur, Tiruvarur, Nagapattinam, and Thoothukudi are also likely to see strong rain spells during this period.
