The city has been without a drop of rain for 49 days, the longest pre-monsoon dry spell in 16 years, but relief in the form of rain is likely in a few days. On February 28, the Met office had recorded 2mm of rain in Alipore. Throughout March and 18 days in April, the city has neither got rain nor its first summer squall.
“A longer dry spell than this was in 2006. The city had then seen 72 consecutive rainless days — from February 1 to April 13,” a Met official said.
The Met forecast said the dry spell was nearing its end.
“Between April 20 and 23, at least one spell of thunderstorm and rain is likely in Kolkata and surrounding areas,” said G.K. Das, director of the India Meteorological Department, Kolkata.
“The conditions are likely to be favourable for the formation of thunderclouds over Jharkhand and adjoining areas. The clouds are likely to move eastward and bring rain to Kolkata,” he said.
There is a chance of the formation of a cyclonic circulation over Jharkhand. If the system takes shape, it will attract moisture-laden easterly winds from the Bay. The westerly winds, already prevalent in the region, will then converge with the easterlies and lead to the formation of thunderclouds, said a Met official.
The intensity of any possible thunderstorm would depend on the strength of the clouds, said the official.
A squall is a storm that usually brings rain. A Nor’wester is a squall that originates over Chhotanagpur Plateau in the late afternoon and sweeps through parts of eastern India over the next three to five hours at a speed of over 45kmph. It is usually followed by a brief spell of rain.
Kolkata has got neither so far this summer. The city’s usual quota is “a couple of squalls in March and around eight in April and May,” according to the Met office.
The city has been reeling under a twin assault of heat and humidity over the past few days. On Friday, the moisture content dipped slightly, paving the way for the maximum penetration of hot and dry westerly winds, which pushed up the Celsius to 37.9 degrees, the highest so far this season.
On Monday, the maximum and minimum temperatures were around 36 and 29 degrees, respectively. The weather was hot and sultry throughout the day.
In the absence of favourable conditions over Jharkhand, a bulk of the easterly winds are now headed towards north Bengal and Northeast.
The districts of north Bengal and Assam have been getting drenched. Districts that are relatively closer to north Bengal, like Murshidabad and Malda are also getting rain and hail storms.