Kolkata: There seems to be no relief from the scorching heat wave which continues lashing Kolkata along with many parts of the state since Sunday.
Alipore weather forecasting office has warned of heat wave in many districts of South Bengak including Bankura, Purulia and Birbhum. The minimum temperature today will likely to remain near 27degree Celsius and the maximum will rotate near 41 degree Celsius.
Although Tuesday was a relief compared to the scorching Monday, a 60-year-old man, as yet unidentified, died of suspected heatstroke while waiting for a train at Garia station. Passersby rushed him to hospital, but doctors could not save him.
Tuesday’s relief came because the humidity remained low. So, even though the mercury climbed to a searing 40.6°C, the discomfort factor also remained low, since it made people sweat less, compared with Monday. Despite the soaring temperature that kept Kolkatans indoors since the heatwave struck last Sunday, the low humidity made the conditions relatively tolerable. Even though the maximum relative humidity soared to 89%, it remained low during the daytime, when the mercury had shot up, preventing sweat.
The heat, however, claimed a life in the city. A 60-year-old man died of heat stroke while waiting for a train at the Garia raliway station.
The no-sweat story has a flip side, though. The low humidity which is keeping the discomfort factor in check, was triggered by the dry, moisture-less wind blowing in from the north and north-westerly directions. Without moisture incursion, thunderstorms have also been kept at bay, prolonging the scorching spell. “Unless winds blow in from the southerly direction or from the Bay of Bengal, it won’t be carrying moisture to create rain-bearing clouds. At present, Kolkata is being singed by dry, hot winds blowing in from the land. It is pushing the mercury up, but keeping it relatively tolerable without the humidity,” said Devendra Pradhan, additional deputy director-general (instruments), India Meteorological Department (IMD).
Usually, in February, the average humidity ranges between 45% and 93%. It drops to around 52% in early April and rises to 89% by the second week of the month. But while humidity has been moderately high so far, it hasn’t coincided with the soaring mercury, said Met officials. “Humidity has been rising in the evening, when the heat goes down. It has been low during the daytime when it’s scorching, so the comfort index has been high. In February, the relative humidity often pushes up to 95%, which leads to sweating. But this time, it has remained under 90%,” said G C Debnath, deputy director-general, Regional Meteorological Centre.
The prolonged heatwave in April, though, is unusual, said the Met office. “While it has already reached its third day in Kolkata, the scorching spell has been continuing for five days in south Bengal. As of now, there is no respite in sight for Kolkata. The city will continue to reel under heatwave conditions for at least three more days. The temperature will hover around the 40°C-41°C mark,” Debnath said.