Heavy rainfall lashed many parts of coastal Tamil Nadu and South coast of Andhra Pradesh during last 2-3 days of the Year. With 201 mm rain Chennai witnessed one of the heaviest 24-hour downpour. In fact, this was the second highest 24-hour rain for Chennai after 2nd December in 2015.
This heavy rain episode seems to be unusual because there was no significant weather system such as low-pressure area or depression which would have induced such heavy downpour. A cyclonic circulation is persisting over southwest Bay of Bengal off Sri Lanka Coast and humid strong North easterly winds are feeding moisture over coastal areas of Andhra and Tamil Nadu.
The last 24 hours saw moderate showers with Nungambakkam in Chennai recording 43 mm of rainfall.
Moderate to heavy rain spells may continue for another 24 hours over coastal areas of Tamil Nadu. Rain will now reduce over Andhra Pradesh coast. Scattered rain may occur over interior Tamil Nadu and parts of Kerala for another 24 hours. Thereafter rain activities will reduce significantly over entire south Peninsula and by January 3rd weather will be almost clear.