Kolkata: The city received overnight rain triggered by a thunderstorm late on Friday and woke up to an overcast sky and steady drizzles that lasted till late on Saturday morning. The rain was accompanied by a hailstorm in some parts of the city, precipitated by two troughs, including one triggered by a western disturbance (WD), that pulled minimum temperature down by six degrees from 25.4°C on Friday to 19.2°C on Saturday. The city received 19.8 mm of rain on Friday and 3.4 mm on Saturday. The rain and the cloud cover pulled the mercury down. The maximum temperature dropped to 23.2°C on Saturday from 30.9°C on Friday, a sharp drop of 7 degrees. It was 11°C below normal. Most parts of the city received continuous downpour from 2 am on Saturday till around 11 am. It was consistent but not very heavy, though. Some parts of south Kolkata received a hailstorm between 2 am and 3 am on Saturday. The thunderstorm and the rain were triggered by a low-pressure trough over south Bengal that hung over the region on Saturday, and a WD that stretched from Haryana to Chhattisgarh. “It was a mixed impact of the two that triggered thunderstorms in Kolkata and in several districts of south Bengal since Friday evening. These were aided by moisture incursion from the Bay that helped precipitate the thunderstorms and rain. While the impact of the WD will reduce from Saturday night, the low-pressure trough over south Bengal, too, will start moving away. This will lead to a clearer sky on Sunday, though localised rain may continue,” said Regional Meteorological Centre (RMC) weather scientist Sourish Bandopadhyay. The city may continue to remain cloudy during the first half of Sunday but there will be no ‘significant rain or thunderstorms’. The mercury, too, will remain significantly lower than normal. While the minimum is expected to be around 19°C, the maximum could be around 29°C. “The cloud cover and the continuing moisture incursion will keep the mercury low. It will rise gradually as the cloud cover lifts over the next 24 hours,” added Bandopadhyay. Bankura, Jhargram, Purulia, West Midnapore and West Burdwan received severe thunderstorms and rain on Saturday. On Friday, Purulia recorded maximum temperature of 36.3°C, the highest in south Bengal, while Raiganj recorded 35°C – the highest in north Bengal. North Bengal received light to heavy rain on Friday. “Several south Bengal districts will continue to receive rain and hailstorms over the next seven days,” said a statement by the RMC.
