Kolkata: The India Meteorological Department (IMD) on Friday issued a cold wave alert for seven South Bengal districts — Purulia, East Burdwan, West Burdwan, Bankura, Jhargram, West Midnapore and Birbhum till December 15.
The minimum temperature in Kolkata dropped to 14 degrees Celsius on Friday morning, which was two degrees below the normal. The weather office said the minimum temperature is likely to be below normal in these districts owing to the northwesterly to northerly winds prevailing in the region. Purulia was the coldest in the state’s plains at 7.5 degrees Celsius on Friday.
It is considered a cold wave when the minimum temperature is less than the 10th percentile of daily value (10 per cent of days that are coldest or below a certain temperature threshold) and at the same time the daily minimum temperature is below 15 degree Celsius. If such conditions are met for three consecutive days, then a cold wave event is declared.
“The minimum temperature is very likely to be below normal by 2 to 4 degree Celsius in all the other South Bengal districts till December 15. Dry north-westerly and northerly winds are blowing at lower levels. The night temperature in these seven districts is expected to drop below normal and cold wave conditions may prevail over the weekend,” said a weather official.
The higher reaches of Darjeeling recorded a minimum temperature of 1.0 degree Celsius on Friday morning, the lowest in the state, while Darjeeling town recorded a minimum temperature of 4 degree Celsius, the MeT office said.
Birbhum’s Sriniketan registered 8.2 degree Celsius on Friday, Asansol 9.5, Burdwan 10, Bankura 11.4, Digha 12, Howrah 11.4, Dum Dum 14, Alipore 14. Minimum temperatures were below normal by 5 degree Celsius or more at some places in the western part of South Bengal and 2 to 4 notches below average at rest of the places in the state, the weather office said.