Thunderstorms, rain likely over next 4 days in Kolkata and districts; orange alert issued for south Bengal today

KOLKATA: An upper air cyclonic circulation over south Gangetic West Bengal and adjoining north Odisha is likely to trigger thunderstorms and rain across several south Bengal districts and Kolkata over the next four days. The circulation extends up to 1.5 km above mean sea level.

"In the presence of favourable wind pattern and strong moisture incursion from Bay of Bengal, enhanced thunderstorm activity very likely over the districts of West Bengal," said a bulletin issued by the Regional Meteorological Centre (RMC) on Thursday.

North 24 Parganas received a severe thunderstorm late on Thursday afternoon with an accompanying wind speed of 40-50 km/hour.

It forced chief minister Mamata Banerjee's aircraft to keep hovering in the sky since the weather was not conducive for landing at Dum Dum airport. Salt Lake received a hailstorm. Most parts of north Kolkata, too, were lashed by a thunderstorm and rain between 3.30 pm and 4.30 pm.

It was a localised system that formed around Dum Dum and affected the northern and eastern fringes of Kolkata. "It didn't go beyond the area. So, central and south Kolkata received no rain on Thursday," said RMC weather scientist Sourish Bandopadhyay.

The city recorded a maximum temperature of 33.2°C and a minimum of 25.8°C.

An orange alert has been issued for entire south Bengal on Friday, with thunderstorms expected at one or two places in all the districts.

"Chances of thunderstorm and rain are high on Friday and Saturday. Thereafter, the city and south Bengal may receive sporadic thunderstorms. There is again a possibility of multiple thunderstorms striking Kolkata and south Bengal districts on March 31," The weather conditions will remain ideal for thunderstorms over the next few days, he added. "Now, we have a circulation. Over the next two days, a trough may form. There is also some impact of a western disturbance. These will keep the city cloudy and generate thunderstorms. The chances of a severe thunderstorm are high on at least one out of the next two days," said Bandopadhyay.

Darjeeling, Kalimpong and Jalpaiguri, too, were lashed by thunderstorms and rain. The rain was moderate, though, in most of the hill districts, but the storms were accompanied by a wind speed of 30-40 km/hour.

Most parts of the city received a continuous downpour from 2 am last Saturday morning 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.