A Met official stated, “A cyclonic circulation lies over Bangladesh & neighbourhood and extends up to 1.5 km above mean sea level creating strong moisture incursion from the Bay of Bengal. Thunderstorms with lightning along with gusty wind speed and thunder squall activity are very likely to continue over the districts of West Bengal till the end of the weekend.”

The IMD warned of rough seas near the coast on Wednesday. The rough conditions are expected due to high-period swell waves with heights ranging from 0.8 to 2.0 metres and current speeds varying from 15 to 105 cm/sec. The waves are expected to have a period of 15 to 17 seconds.

On Wednesday, Kolkata recorded 30.4 degrees Celsius temperature during daytime which is 5.3 degrees lower than normal temperature with the maximum humidity at 95 per cent. The sky remained generally cloudy with a chance of rain/thundershower.

Cyclonic circulations, rain, and thunderstorms are causing the maximum temperature to be at or below 35 degrees Celsius. On Wednesday, places like Midnapore, Krishnanagar, Asansol, and Jhargram had a maximum temperature of around 33.5 degrees Celsius. Purulia, Sriniketan, Canning, Kalyani, and Birdhwan had a maximum temperature of 44 degrees Celsius, while Panaghar was at 35 degrees Celsius.

Darjeeling, Kalimpong, Alipurduar, Coochbehar, Jalpaiguri, North Dinajpur, South Dinajpur, and Malda have been given a yellow alert for thunderstorms with lightning and gusty wind speed reaching 40-50 kmph, including light to moderate rain, which is expected to continue until this week. Meanwhile, the maximum temperature in Darjeeling was 16 degrees Celsius on Wednesday, Kalimpong was at 19 degrees Celsius, Jalpaiguri and Cooch Behar were at 30 degrees Celsius, Alipurduar and Malda were at 32 degrees Celsius, and Raiganj was at 35 degrees Celsius.