THIRUVANANTHAPURAM: The Central Meteorological Department has warned of isolated heavy rains in the state on Sunday. Yellow alert has been sounded in Ernakulam, Idukki, Kannur and Kasaragod.

The monsoon is expected to intensify under the influence of low pressure formed in the north eastern Bay of Bengal. The low pressure area will move in a north-westerly direction gaining strength and is likely to be the first extreme low pressure of the monsoon. It will weaken by Friday. Authorities have warned fishermen not to go fishing off the coast of Kerala as there is a possibility of strong winds.