Heavy rain to persist across Tamil Nadu as northeast monsoon gathers pace

Heavy rainfall will continue across Tamil Nadu until at least October 23 as the northeast monsoon enters an active phase, according to forecasts by the Regional Meteorological Centre in Chennai.

Sustained downpours over the weekend have significantly boosted water storage across the state, bringing Tamil Nadu's monthly rainfall deficit down to just 3 per cent, well within normal operational parameters. An upper air cyclonic circulation over northern Tamil Nadu and adjoining coastal Andhra Pradesh continues to feed moisture into the region, maintaining steady precipitation across urban and rural belts alike.

Rain in Chennai and northern districts

State weather stations reported widespread activity in the 24 hours to Saturday morning, with 84 locations registering heavy rain. Uthiramerur in Kancheepuram district recorded the highest single-day figure at 15 cm, followed by heavy spells in Kallakurichi, Perambalur, Tiruvannamalai and Chennai.

Chennai recorded its first major downpour of the monsoon season on Saturday evening. Municipal monitoring systems under the Greater Chennai Corporation logged heavy localized accumulation within a few hours, prompting swift field monitoring by civic teams across key zones.

Regional alerts and monsoon outlook

The Regional Meteorological Centre has issued a yellow alert for 17 districts, focusing on northern and interior areas including Cuddalore and Tiruchi. Chennai and its neighboring coastal districts are scheduled to receive further intense spells.

Regional Weather Forecasting Centre head V.R. Durai confirmed that interior and delta districts, many of which had been experiencing lower water levels, stand to gain substantial inflow through October 23. Extremely heavy localized showers reaching up to 20.4 cm are anticipated along the Western Ghats region, particularly in the Nilgiris and Theni districts on October 20.

Although a low-pressure area is developing over the southwest Arabian Sea around Monday, forecasters do not expect it to disrupt current landward precipitation patterns over Tamil Nadu. Overall rainfall intensity across the state is projected to taper off after October 25, ahead of a fresh weather system expected over the Bay of Bengal late in the month.