IMD forecasts heavy rain in Nilgiris, Coimbatore for 3 days from April 30
Synopsis
Well before the southwest monsoon arrives, a persistent low-pressure trough stretching from Karnataka to the Gulf of Mannar is set to drench Tamil Nadu's Western Ghats and southern districts. The Nilgiris and Coimbatore face three straight days of heavy rain, with the system gradually pulling Madurai, Sivaganga, and Virudhunagar into its path by 2 May.
Key Takeaways
IMD's RMC Chennai has forecast moderate to heavy rainfall across Tamil Nadu from 30 April 2025 .
Nilgiris and Coimbatore face heavy rainfall for the next three days , with landslide and waterlogging risks flagged.
Erode , Salem , Dharmapuri , and Krishnagiri are under heavy rain alert for the next two days .
On 2 May , heavy rain is predicted in Dindigul , Theni , Madurai , Sivaganga , and Virudhunagar .
A low-pressure trough at 0.9 km above sea level, stretching from north interior Karnataka to the Gulf of Mannar , is driving the weather system.
Fishermen have been advised to avoid the southern coast; rainfall is pre-monsoon and linked to localised atmospheric instability.
The India Meteorological Department's Regional Meteorological Centre (RMC) in Chennai has forecast moderate to heavy rainfall across several districts of Tamil Nadu, with particular intensity expected over the Western Ghats and coastal regions of South Tamil Nadu, beginning 30 April 2025. The forecast comes ahead of the southwest monsoon season, with current rainfall attributed to localised atmospheric instability.
Weather System Behind the Rainfall
According to an official statement issued by the RMC Chennai, a trough of low pressure persists at an altitude of approximately 0.9 km above mean sea level. The system extends from north interior Karnataka to the Gulf of Mannar, passing through south interior Karnataka and Tamil Nadu. Meteorologists say this atmospheric condition is likely to trigger widespread rainfall activity across multiple districts in the state.
Light to moderate rainfall accompanied by thunderstorms and lightning is expected at isolated places along the Western Ghats districts, coastal belts, delta regions, and the Karaikal area. These conditions are likely to prevail through the day, with intermittent spells of rain in vulnerable pockets.
Districts Under Heavy Rainfall Alert
The Nilgiris and Coimbatore districts face the most significant impact, with heavy rainfall forecast for the next three days, raising the possibility of localised disruptions in hilly and adjoining areas. Authorities have advised residents in these districts to remain cautious, particularly in regions prone to landslides or waterlogging.
Districts including Erode, Salem, Dharmapuri, and Krishnagiri are also expected to receive heavy rainfall over the next two days. The weather system is gradually shifting southward, bringing more districts under its influence.
Day-by-Day Rainfall Forecast
On 1 May, isolated heavy rainfall is likely in Tiruppur, Dindigul, and Theni districts. The intensity is expected to persist on 2 May, with heavy rainfall predicted in parts of Dindigul, Theni, Madurai, Sivaganga, and Virudhunagar districts.
Advisories for Residents and Fishermen
Officials have urged local administrations to remain alert and ensure preparedness, especially in low-lying and flood-prone areas. Fishermen have been specifically advised to exercise caution along the southern coast due to potential adverse weather conditions. Notably, with the southwest monsoon still weeks away, this current spell of rainfall is attributed to localised atmospheric instability rather than seasonal monsoon activity.
As the system continues its southward movement, more districts could come under its influence in the coming days, and residents are urged to monitor official weather updates regularly.
Point of View
Already one of India's most ecologically fragile hill districts, faces three consecutive days of heavy rain with the monsoon still weeks out. The real question is whether district administrations, particularly in Coimbatore and the Nilgiris, have activated preparedness protocols rather than simply issuing advisories. Repeated warnings without on-ground readiness have historically preceded preventable tragedies in Tamil Nadu's hilly terrain.
NationPress
23 Jul 2026
Frequently Asked Questions
Which districts in Tamil Nadu are under heavy rainfall alert from April 30?
The Nilgiris and Coimbatore districts face heavy rainfall for the next three days, while Erode, Salem, Dharmapuri, and Krishnagiri are on alert for the next two days. By 2 May, Dindigul, Theni, Madurai, Sivaganga, and Virudhunagar are also expected to receive heavy rain.
What is causing the rainfall in Tamil Nadu before the monsoon?
A trough of low pressure at approximately 0.9 km above mean sea level, extending from north interior Karnataka to the Gulf of Mannar, is driving the current spell. IMD has clarified this is due to localised atmospheric instability and is not related to the southwest monsoon, which is still weeks away.
Has IMD issued any advisory for fishermen in Tamil Nadu?
Yes, fishermen have been advised to exercise caution along the southern coast of Tamil Nadu due to potential adverse weather conditions associated with the ongoing low-pressure system.
When is the southwest monsoon expected to arrive in Tamil Nadu?
According to IMD, the southwest monsoon is still weeks away. The current rainfall is attributed to localised atmospheric instability rather than monsoon activity.
What precautions have authorities recommended for residents in affected districts?
Officials have urged residents in hilly and low-lying areas — particularly in the Nilgiris and Coimbatore — to remain cautious about landslides and waterlogging. Local administrations have been asked to stay on alert and ensure preparedness in flood-prone zones.
