The weather department on Thursday forecast heavy rainfall in all south Bengal districts till Friday under the influence of a depression in the Bay of Bengal and advised fishermen not to venture into the sea.

“The depression is likely to cross the Orissa coast tonight and under its influence heavy rainfall may occur in all south Bengal districts,” regional met director G C Debnath said in Kolkata. “Fishermen are advised not to venture into the sea till Saturday,” he said.

The depression, which was 800 km south west of Kolkata at 11:30 am (IST) on Thursday morning, is likely to move in a north-north westerly direction, the weather office said in its forecast.

In Orissa, rains pounded most parts of the state and fishermen there were also asked not to go out to sea.

The local met office advised hoisting of local cautionary signal-III at all Orissa ports.

Heavy to very heavy rainfall was likely at few places over coastal Orissa and heavy rain at one or two places over interior parts during the next 48 hours, the met office said, adding rain or thunder shower would occur at most places.

Under the impact of the depression, squally winds with speeds reaching 45-55 km per hour was likely to be experienced along and off the coast till tomorrow.