Kolkata, May 20 (IANS): Cyclonic storm "Roanu", formed over the Bay of Bengal, is set to intensify and bring heavy to very heavy rains in West Bengal from Friday night, the Regional Meteorological Centre (RMC) said.

"Thundershowers due to Roanu will lash Bengal districts and Kolkata starting late evening today (Friday). Roanu is likely to cross coastal Bangladesh on May 21 night or early morning on May 22. On the way, the cyclone will hit Bengal," said an official at the RMC here.

Rainfall would continue till Sunday, the official said.

The India Meteorological Department (IMD) issued a cyclone alert for coastal Bengal on Friday and has also intimated the state chief secretary.

Sea waves are very likely to be high to very high along and off Bengal coast during next 48 hours, the IMD said.

"Damage (expected) to thatched huts, minor damage to power and communication lines and major damage to kutcha and minor damage to pucca roads over north coastal Andhra Pradesh during next 24 hours, over coastal Odisha and coastal West Bengal during next 48 hours," the IMD said.