The Regional Meteorological Centre (RMC) has issued a heavy rainfall alert for several districts in western Tamil Nadu, warning of sustained wet weather from Friday, April 25 through at least May 2, 2025. Districts including Nilgiris, Coimbatore, and Erode are on high alert as a low-pressure system over Tamil Nadu and surrounding regions continues to intensify. Authorities have urged residents in flood-prone areas to stay vigilant and monitor official weather updates closely.

Low-Pressure System Driving Widespread Rainfall

Meteorologists at the RMC Chennai confirmed that a persistent low-pressure system hovering over Tamil Nadu and adjoining areas is the primary driver behind the extended rainfall forecast. The system is expected to sustain precipitation activity for nearly a week, offering significant relief from the intense pre-summer heat that has gripped the state.

According to the latest weather bulletin, widespread rainfall activity is anticipated across the state between April 30 and May 2. Districts situated along the Western Ghats, as well as coastal belts in southern Tamil Nadu, are expected to receive moderate to heavy showers during this window.

The orographic effect — where moisture-laden winds are forced upward by mountain terrain — is likely to amplify rainfall intensity in hilly zones, making areas like Nilgiris particularly susceptible to heavier downpours.

Key Districts Under Alert: Salem, Krishnagiri, and Dharmapuri

The weather department has issued a specific high-alert for May 1 and May 2, targeting inland districts such as Salem, Krishnagiri, and Dharmapuri. These regions are expected to experience intense showers accompanied by gusty winds, raising concerns over localised disruptions to transport and daily life.

Additionally, delta districts and coastal belts across Tamil Nadu are forecast to receive moderate rainfall during the same period. Authorities have warned that intermittent heavy spells could cause waterlogging in low-lying pockets across urban and semi-urban areas.

Strong Surface Winds Up to 40 kmph Expected

Alongside rainfall, the RMC has flagged the likelihood of strong surface winds reaching up to 40 kmph across several districts during the rain-bearing period. These gusty conditions could pose risks for outdoor activities, construction sites, and vulnerable infrastructure.

Fishermen along the Tamil Nadu coast have been specifically advised to avoid venturing into the sea during this period, as sudden weather changes could prove hazardous. The department has urged all coastal communities to remain updated with real-time weather advisories.

Impact on Daily Life and Precautionary Measures

While the rainfall is expected to bring much-needed relief from prevailing heatwave conditions across Tamil Nadu, it also brings associated risks. Officials have cautioned district administrations to remain on standby for contingencies such as fallen trees, power outages, and minor flooding incidents.

Residents in low-lying and flood-prone zones have been advised to take preventive measures and avoid unnecessary travel during peak rainfall hours. Local bodies have been put on alert to ensure swift response to waterlogging complaints and infrastructure damage.

This rainfall episode comes amid Tamil Nadu's broader vulnerability to extreme weather events — the state has witnessed increasingly erratic monsoon patterns over the past decade, with both drought years and devastating floods becoming more frequent. The 2015 Chennai floods and the recurring inundation in delta districts have repeatedly exposed gaps in urban drainage and disaster preparedness infrastructure.

What to Expect Next

The Regional Meteorological Centre is closely monitoring the low-pressure system and is expected to issue updated bulletins as the situation develops. If the system intensifies further, additional districts could be brought under alert. Residents and local authorities should watch for RMC advisories on April 30 and May 1 for revised forecasts covering the final phase of this wet spell.

With the southwest monsoon still weeks away, this pre-monsoon rainfall activity is critical for replenishing reservoirs and easing agricultural stress across Tamil Nadu's interior districts.