A Tornado over northwest Assam and adjoining West Bengal on 19 April 1963

Abstract

On the evening of 19 Apri1 1963 a tornado passed over a few places in Cooch Behar district of North Bengal and adjoining Goalpara district of North Assam. Details of the tornado as far as could be gathered from on-the-spot enquiries have been presented in the paper. The area is frequented with severe thunder squalls hailstorms, but this one caused the biggest havoc in living memory. The tornado had a track of 36 km. The diameter of the funnel of the tornado where it touched the ground was l00-130m. The rotation was anticlockwise. At three places, the funnel itself showed spiralling motion. There was practically no rain in and around the area affected by the tornado, Hailstones as large as 14 cm in diameter could be observed. The meteorological conditions showed high probability of occurrence of severe thunderstorm over North Assam with possibilities of large hail.