A family on a Sunday outing, armed with an umbrella. Picture by Amit Datta

The weather in Calcutta and its adjoining areas may improve gradually from Monday afternoon.

The low pressure that lay on the north Bay of Bengal on Saturday could not intensify into a depression as it entered land on Sunday morning and hovered over the Bengal coast. It is expected to move towards Orissa.

“The low-pressure belt can cause heavy to very heavy rain in the coastal zone. In Calcutta and its adjoining areas, there are chances of moderate rain. A few spells in Calcutta may be heavy till Monday noon,” said G.C. Debnath, the director of the weather section at Regional Meteorological Centre, Alipore.

The city recorded 14.4 mm of rain in 24 hours, till 5.30pm on Sunday.

The low-pressure belt hardly moved throughout Saturday, feeding on moisture from the Bay. “It was a strong system, which we thought might develop into a depression,” said a Met official.

As the system is showing signs of moving towards Orissa, the intensity of rain in Calcutta will decrease from Monday noon. “But there will still be occasional spells of rain in the city and its adjoining areas in the next few days, as the monsoon current is active over south Bengal,” said a Met department official.

The civic body was “on alert” on Sunday. An official said a team of drainage department employees, led by an executive engineer, was stationed at the SN Banerjee Road headquarters to tackle any emergency. The last time Calcutta received a heavy shower was on August 13, when it rained 83 mm in three hours from 8.30am.

The Met office, however, has issued a “heavy rainfall” warning for East and West Midnapore, Purulia and Bankura districts. “At some places, the rainfall could be as high as 250mm.”