Northeast monsoon gathers momentum in Tamil Nadu; unleashes another round of downpours over Chennai

The Northeast monsoon has shifted into a vigorous phase, bringing intense spells of rain overnight across Tamil Nadu, particularly the north coastal districts.

The spell of wet weather is expected to continue till October 26, 2026 with a low pressure area forming over southwest Bay of Bengal off Tamil Nadu during early hours of Wednesday (October 21). A trough runs from the centre of this low pressure area over Bay of Bengal and adjoining TN coast to north coastal Andhra Pradesh. The system is being monitored for further strengthening.

Rainfall in Chennai

Multiple weather systems over the Bay of Bengal are expected to sustain intense rainfall across the State this week. Several areas in and around Chennai received heavy overnight downpour, with MGR Nagar in Chennai topping the charts with 15 cm in the 24- hour period ending 8.30 a.m. on Wednesday.

Chennai witnessed heavy rains in the night hours on October 20, 2026. A scene at Anna Salai in Thousand lights
| Photo Credit:
B. Velankanni Raj

Torrential downpour had pounded several areas in Chennai and fringes – Vadapalani (14 cm), Saidapet, Meenambakkam, Alandur, Kancheepuram (13 cm each); DGP office, Madipakkam, Valasaravakkam, Maduravoyal (12 cm each); Nungambakkam, Nerkundram, Adyar (11 cm each); Korattur (10 cm) and Ambattur, Saligramam, Puzhal, R.A. Puram, Ayapakkam, YMCA Nandanam, Parrys , Anna University, Manali, Anna Nagar West and Pozhichalur, (9 cm each).

Widespread showers across districts

Many other districts, including Kanniyakumari, Kancheepuram, Tiruppur, Ramanathapuram, Tenkasi and Virudhunagar too received moderate to heavy spells of rain.

Rain lashed Thoothukudi on October 20, 2026
| Photo Credit:
N. Rajesh

Rain-bearing clouds continued to sweep across various parts of Tamil Nadu, sustaining the wet spell on Wednesday.

Another low pressure area: RMC

In its latest update, the Regional Meteorological Centre (RMC) in Chennai has noted that low pressure area over Southwest Arabian sea is likely to move towards the Somalia coast and may not have significant impact over Tamil Nadu region. The weather agency has also forecast another low pressure area brewing over Southeast and adjoining east central Bay of Bengal around October 23.

The RMC is monitoring the system for its strength and movement for any potential rainfall impact over Tamil Nadu. The system is currently represented by an upper air cyclonic circulation over Gulf of Thailand and adjoining Myanmar region, far away from Tamil Nadu.

Overcast sky on the Chennai-Bengaluru National Highway at Ranipet district on October 21, 2026
| Photo Credit:
C. Venkatachalapathy

As the monsoon remains active and weather systems line up over the seas, the southern and delta districts of Tamil Nadu are likely to receive more intense spells as Wednesday (October 21) progresses.

South coastal districts including Thoothukudi, Tirunelveli and Kanniyakumari are in the path of very heavy rainfall till Thursday (October 22) morning. Various south, delta and interior districts, including Karur, Dindigul, Pudukottai and Thanjavur also have prospects of heavy rainfall.