The weather office forecast thunderstorms with lightning in the region till Monday, and in northern West Bengal till Wednesday owing to a cyclonic circulation lying over north Bangladesh and strong moisture incursion from the Bay of Bengal. On Saturday, Kolkata’s maximum temperature was recorded as 37.4 degrees Celsius and the minimum as 28.5 degrees Celsius.

Heatwave conditions were observed in areas of Purulia, Bankura, Paschim Bardhman, Purba Bardhman, Murshidabad and Birbhum districts on Saturday.

Thunderstorms are likely in districts like Howrah, Hooghly, Kolkata, Nadia, North 24 Parganas, and South 24 Parganas between Sunday and Monday.