Met officials on Sunday warned that heavy rain is expected in Calcutta and the south Bengal districts during the next 48 hours. They ruled out a Mumbai-like deluge, though.

The officials explained that the monsoon current in the state was strong and very active. Besides, the two troughs of low pressure that had formed over Gangetic Bengal were causing heavy incursion of moisture from the Bay of Bengal.

The city recorded a maximum humidity of 96 per cent on Sunday. The minimum humidity was 75 per cent.

“There is a trough of low pressure extending from Jharkhand to Assam, across central Bengal and Bangladesh. The other trough stretches from west Rajasthan to the Andaman Sea, across east Madhya Pradesh, north Chhattisgarh, Jharkhand, Gangetic Bengal, north Bay and east-central Bay. Because of these two factors, we expect heavy rain during the next two days,” a Met official said.

There were a few light drizzles in and around the city on Sunday.