The term ‘Kalbaisakhi’, referring to a local summer storm, mainly affects which regions?

The term Kalbaisakhi refers to a violent local summer thunderstorm that mainly affects the eastern and northeastern regions of India, especially:
West Bengal
Odisha
Bihar
Jharkhand
Assam and other northeastern states
It also occurs in Bangladesh, where it is equally well known.
Explanation
Nature of the storm: Kalbaisakhi (also called Nor’wester) is a pre-monsoon thunderstorm.
Season: It usually happens during March to May (the hot months before the monsoon).
Cause:
Intense heating of the land during the day creates strong upward air currents.
Moisture from the Bay of Bengal feeds these currents.
This leads to the formation of cumulonimbus clouds, which trigger sudden storms.
Features:
Strong winds (sometimes gale-force)
Heavy rain with hail
Frequent lightning
Sudden drop in temperature
Impact
Positive: Brings relief from the scorching summer heat.
Negative: Damages crops, houses, and can be dangerous due to lightning and hail.
In short, Kalbaisakhi is a signature summer storm of eastern India and Bangladesh, feared for its destructive power but also welcomed for cooling down the oppressive heat.