A well-marked low-pressure area over southwest Bay of Bengal intensified into a depression on Thursday morning packing wind speed of 40-50 kmph as it moved towards the north Tamil Nadu coast, the weather office said.
As many as 12 teams were deployed and five teams were on standby in West Bengal while additional teams are also in readiness if required.
The cyclone expected to weaken gradually over the next two days.
The southwest monsoon is likely to arrive over Kerala on May 31, a day earlier than its normal onset date, the India Meteorological Department (IMD) said.
Conditions are becoming favourable for onset of southwest monsoon over Kerala during next two to three days, according to India Meteorological Department in Pune.
The much-awaited south-west monsoon on Monday brought first showers to the Andaman and Nicobar islands, setting the stage for its early progression towards Kerala.The onset of monsoon has now set the stage for the four-month rainfall season that has been eagerly awaited by the agricultural community who had to bear the brunt of a severe drought last year.The weather office said conditions were favourable for further advancement of the monsoon over more parts of Bay of Bengal
It has also advanced into most parts of Tamil Nadu, some parts of south interior Karnataka and remaining parts of south Bay of Bengal, according to IMD.
According to reports, the very severe cyclonic storm, located over west-central and adjoining south Bay of Bengal, has weakened into a severe cyclonic storm.