Northeast monsoon rains have arrived in coastal Tamil Nadu and Puducherry (Representational)
The northeast monsoon sets in over parts of south India today and would expand in the next 24 hours, the regional weather office said.
This time, there could be excess rainfall during northeast monsoon, Director of Area Cyclone Warning Centre, S Balachandran told reporters in Chennai.
"Northeast monsoon rains have commenced over coastal Tamil Nadu and Puducherry, south Tamil Nadu, southern Kerala and southern coastal areas of Andhra Pradesh," he said.
The monsoon will cover the remaining parts of Tamil Nadu and Kerala, Rayalaseema and southern Karnataka tomorrow, he added.
Tamil Nadu is dependent on the crucial north east monsoon as it brings the bulk of the annual rainfall in the state.
According to Indian Meteorological Department (IMD), the long period average rainfall for Tamil Nadu during the north east monsoon stretching between October and December was 44 cm and this time there could be an excess rainfall.
The forecast was for an "above normal" monsoon, it said adding "there are still two months left."
Mr Balachandran predicted showers in most parts of the state and Puducherry on November 2 and 3, while heavy rain was likely in one or two places in coastal districts.
There would be occasional spells of rains or thundershowers in Chennai and its suburbs, he added. In the last 24 hours in Tamil Nadu, Puzhal recorded 11 cm rainfall while Kelambakkam recorded 10 cm.