Kolkata: The deep depression over the Bay of Bengal may turn into a cyclonic storm by Saturday evening and hit the adjoining coasts of West Bengal and Bangladesh on the night of May 26, the weather office said.

It said that the cyclone is likely to make landfall with wind speed ranging from 110-120 km per hour to 135 km per hour.

The weather office has warned of extremely heavy rainfall over coastal districts of West Bengal and northern Odisha on May 26-27.

Extremely heavy rainfall may occur over parts of Northeast India on 27-28 May.

There is a possibility of inundation of low-lying areas of coastal West Bengal and Bangladesh due to storm surge of up to 1.5 meters at the time of landslide.The weather office has warned fishermen not to venture into the sea in North Bay of Bengal till the morning of May 27.

The weather department has issued a red alert for the coastal districts of South and North 24 Parganas of West Bengal on May 26 and 27, where extremely heavy rainfall is likely at some places.

Weather System - A deep depression, located over east-central Bay of Bengal, about 380 km south of Sagar Island in South 24 Parganas district, is likely to concentrate into a cyclonic storm by Saturday evening and move northwards.'' Bulletin.

It is likely to intensify into a severe cyclonic storm by Sunday morning and make landfall near Saga Island and Khepupara around midnight on Sunday with wind speed of 110 to 120 kmph gusting to 135 kmph, the bulletin said. The beach may cross West Bengal and adjacent Bangladesh coasts.

This is the first cyclone in the Bay of Bengal this pre-monsoon season and will be named Remal, given by Oman, as per the system of naming cyclones in the North Indian Ocean region.An orange alert was issued by the weather department for Kolkata, Howrah, Nadia and East Medinipur districts on May 26-27 with wind speed ranging from 80 to 90 kmph gusting to 100 kmph and thunderstorm at one or two places. There was a warning of heavy to very heavy rain.

Wind speed will reach 60 to 70 kmph gusting to 80 kmph with heavy rain in Hooghly, East Bardhaman and Paschim Medinipur districts.

It said that in other districts of South Bengal, wind will blow at a speed of 40 to 50 km per hour to 60 km per hour.

In North Odisha, coastal districts of Balasore, Bhadrak and Kendrapara will receive heavy rainfall on May 26-27, while Mayurbhanj is likely to receive heavy rainfall on May 27.

The India Meteorological Department has warned of localized flooding and heavy damage to weak structures, power and communication lines, unpaved roads, crops and gardens in South and North 24 Parganas districts of West Bengal.People in affected areas have been asked to stay indoors and evacuate vulnerable structures.