Sun to come out, mercury to rise before dipping again on weekend
Times of India | 4 February 2025
123 Kolkata: The city has been experiencing abnormally high temperatures over the past few days but from Tuesday, the fog and the cloud cover is expected to clear up, leading to a slide in mercury. The Met officials have predicted a mercury rise again on Thursday and Friday before it starts dipping by the weekend, inching towards the 15°C-mark before winter ends for good this season.
The minimum temperature has been hovering over 20°C in the past six days, significantly higher than the normal mark, making the nights relatively warm. The maximum temperature, however, stayed around the normal mark on all these days. The Met officials blamed moisture incursion from the Bay of Bengal and the missing cold-bearing northwesterly wind for this current warm spell and the fog in the mornings.
"The high moisture content and very feeble wind speed were the main factors for the significantly high minimum temperature and the fog. From Monday, we started getting the northwesterly wind, and this will push the mercury down by a few notches in the next two days," said HR Biswas, head (weather forecast section) at the Regional Meteorological Centre, Kolkata.
Along with the fog in the morning, the city also had a cloud cover at a low level in the past few days, keeping the sun at bay. The Met officials said less solar insulation due to the fog and cloud cover kept the maximum temperature under check, while the high moisture content kept the minimum temperature markedly high. Even as Kolkata escaped with shallow to moderate fog, many districts, including the neighbouring 24 Parganas, encountered dense fog.
According to the Met officials, an anti-cyclonic circulation injected moisture in abundance from the Bay of Bengal into the land in the past few days. In the absence of a strong gust of wind, the moisture content concentrated at a lower level, triggering fog formation. The anti-cyclonic circulation has now moved towards the Odisha coast.
The minimum temperature surged to the 20°C-mark for the first time this winter on Jan 30 when the city recorded 21°C. Since then, it remained around the 22°C-mark. On Monday, it was 22.6°C, 6.6°C notches above the normal mark. The Met officials said that very rarely did the minimum temperature stay above 20 for such a long spell in Kolkata during the winter. The maximum temperature, at 27.2°C, however, was only 0.2 notches above the normal mark.
"Once the sky clears up, the gap between the maximum and minimum temperature should also go up, which at present is not very significant," added Biswas.