Bordoisila
Kalbaisakhi
Severe storms in Eastern India and Bangladesh
A kalbaisakhi (Odia: କାଳ ବୈଶାଖୀ) (Bengali: কাল বৈশাখী), also known in Assam as a bordoisila and in some English publications as a nor'wester, is a localised rainfall and thunderstorm event which occurs in Bangladesh as well as the Indian states of Bihar, Jharkhand, Odisha, Tripura, Assam, and West Bengal during summer. These storms generally occur in the afternoon or just before sunset, when thick dark black clouds start appearing over the sky and then bring gale-speed wind with torrential rain, often with hail, but spanning only a short period of time.[1][2]