The mercury touched the 40-degree mark in the city and several other districts on Sunday, making it the hottest day of the season.
The maximum temperature recorded at Alipore during the day was 39.6 degrees Celsius, four notches above normal.
In Dum Dum, the maximum temperature was 40.5 degrees.
The mercury breached the 40-degree mark in several places in south Bengal like Asansol, Sriniketan and Medinipur.
The Met office declared “heatwave conditions” in North 24-Parganas, Paschim Medinipur, Paschim Bardhaman, Birbhum and Malda.
A heatwave is issued when the mercury breaches the 40-degree mark and the maximum temperature is five notches above normal, said a Met official.
The conditions in Kolkata were not much different than the places under heatwave. However, a formal declaration from the Met office will come only if the maximum temperature recorded at Alipore touches 40 degrees.
The hot spell is likely to continue for the next few days, said a Met official.
The last time the city was under the grip of a heatwave was in April 2016. The maximum temperature on April 11 in 2016 was 41.3 degrees.
Officers at the Regional Meteorological Centre in Alipore said the rise in temperature was because of a change in the wind-flow pattern that has been a feature of this summer.
“Dry and hot winds have been flowing from the north-western parts of the country and the temperature is shooting up. As there is no wind from the south, there is virtually no incursion of moisture from the Bay of Bengal. So, the dry heat is searing us,” said G.K. Das, director, IMD, Kolkata.
The past few days had been humid. But Sunday was much drier. The minimum relative humidity was around 30 per cent. The low moisture content in the atmosphere granted free access to the hot and dry westerly winds, said Das.
Kolkata is yet to weather the first Nor’wester this season. By this time, the city usually has two to three Nor’westers. But this year, there have been none.
“Only a Nor’wester can cool down the city. But, we can’t expect any thunderstorm activity right now as there is little moisture in the atmosphere during the day,” the official said.
The Met office had predicted thunderstorms in Kolkata last week. But there were none.
Sunday was a holiday and most Kolkatans were spared the ordeal of stepping out of their homes. But those who did had to endure the assault of the blazing sun.
Traffic policemen across the city were seen splashing water on their faces at regular intervals.
Pedestrians walked with their heads and faces covered with handkerchiefs or scarves. Those without a proper cover used bags.
Partha Saha, a businessman in Tollygunge, drove his daughter to her dance classes on Sunday morning.
He had kept the car parked in the open outside the school. When he came back after around 20 minutes, the seats were burning. “Even after switching the AC on, it made no difference,” said Saha.
At homes, fans at full pelt seemed to spit hot air.
The forecast looked bleak.
“There is very little chance of any thunderstorm activity over the next four to five days. The city will continue to sizzle. The maximum temperature is unlikely to come under 38 degrees,” said Das.
