The northeast monsoon will hit coastal areas of Tamil Nadu and Puducherry during the next 24 hours before gradually extending to other parts of the region, the weather office in Chennai said on October 31.

Chennai and adjoining areas such as Ennore, Kelambakkam and Mahabalipuram recorded 5 cm rainfall each in the last 24 hours ending 8.30 a.m. on October 31, as against 1 cm recorded the day before.

Tamil Nadu depends on the northeast monsoon, also known as retreating monsoon, as it brings much of the annual rainfall to the State.

With a month’s delay in arrival of the three-month-long (October to December) monsoon, the Met department said the next two months would be crucial.

In September, the Indian Meteorological Department had forecast 12% surplus rainfall for Tamil Nadu from the northeast monsoon (NEM).

Director of Area Cyclone Warning Centre, S. Balachandran said coastal areas of Tamil Nadu and Puducherry would first experience the northeast monsoon in the next 24 hours beginning 1 p.m. IST on October 31. “It would gradually extend to rest of Tamil Nadu and adjoining areas of south Karnataka and Kerala during the subsequent days,” he said.

Attributing the delay in the onset of monsoon to Cyclone Titli and Luban that formed over Bay of Bengal and Arabian Sea, respectively, early this month, Mr. Balachandran said the next two months would be crucial. “We will have to wait and watch,” he said.