A favourable wind and moisture incursions over the Bay of Bengal will bring thunderstorms and light to moderate showers over parts of northern and southern Bengal. Kolkata will also feel the impact. These are expected to take place from April 10 to April 14.

Thus, the weather is likely to cool down just before the advent of Poila Baisakh, the beginning of the new year (Baisakh 1) according to the Bengali calendar, on April 15.

The information was conveyed through a special bulletin brought out this afternoon by the India Meteorological Department’s (IMD) regional centre at Alipore in Kolkata.

Gusty winds of around 30-40 kmph and light to moderate showers are also expected to hit Kolkata over these five days, Sourish Bandhopadhyay, scientist at Alipore’s Met office told The Telegraph Online.

According to the special bulletin, there is an orange alert (implying ‘be prepared to take action’) for the districts in the northern part of the state (Darjeeling, Jalpaiguri, Coochbehar, Malda, North Dinajpur, South Dinajpur) from April 10 to 12.

For the districts in the eastern and western regions (Nadia, East Burdwan, West Burdwan, Bankura, Birbhum, Purulia, Murshidabad), a yellow alert (implying ‘be on the watch’) has been announced for April 10 and 11 and an orange alert for April 12 and 13 (including Hooghly).

A yellow alert is out for some of the districts of southern Bengal (Jhargram, East Midnapore, West Midnapore) and Purulia.