As summer approaches, the city is likely to have its first spell of thunderstorms early next week.
“Thunderstorm with rain” is the official forecast for Calcutta on Monday. “Partly cloudy sky with possibility of development of thunder/lightning” is in store for Tuesday, according to the Met office.
A Met official said a drizzle on Sunday was not ruled out.
“The upper air cyclonic circulation over Odisha and neighbourhood extending up to 1.5 km above mean sea level persists. The trough from the above cyclonic circulation over Odisha and neighbourhood to northwest Uttar Pradesh across north Chhattisgarh and northeast Madhya Pradesh at 0.9km above mean sea level persists,” said the daily weather report released by the Met office in Alipore.
“There will be a rise in moisture incursion from the Bay of Bengal. The earth’s surface receives sufficient heat. The heat and humidity will create rain-bearing thunderclouds,” a Met official said.
The intensity of the showers will be greater in north Bengal. South Bengal districts such as Murshidabad, Birbhum and East and West Burdwan may also receive a strong spell of rain and winds, said the official.
As of Saturday evening, light rain with moderate gusts of wind (30 to 40kmph) is likely in Calcutta. The showers are most likely on Monday and Tuesday. There might be a drizzle or two on Sunday as well, he said.
The winter had been exceptionally dry in south Bengal. In the early hours of February 24, rain and gusts of wind lashed Calcutta. The showers, which many slept through, were the first in the city in nearly four months.
The mercury is slowly rising. The weather was dry even on Holi, but as summer approaches, the humidity quotient will be rising, said Met officials.
On Saturday, the minimum relative humidity was around 50 per cent, up from around 35 per cent even a week ago. The showers might bring the day temperature down, but the relief will not last long, they said.