The frequency of damaging local storms preceding the monsoon usually reaches its peak in April, while a few occur in May and the fewest in March. Wind shear and instability are maximized during this period, as warm, moist air flows northward from the Bay of Bengal and combines with a westerly wind in the upper atmosphere. This makes Bangladesh one of the most disaster-prone countries in the world today. They are capable of experiencing possible tornadoes of F4 or even F5 intensity. Unfortunately, Bangladesh is also the country where the deadliest tropical cyclone in history hit. On November 11, 1970, "Cyclone Bhola" killed at least 300,000 people after sending a storm surge 20 to 30 feet high onto the low-lying coasts of Bangladesh. I already mentioned that Bangladesh was already going through a drought at the time of this tornado so I want to talk a little more about that. Drought is a major problem for many countries. In Bangladesh, the causes of drought are linked to unavailability of surface water resources and climate variability. The direct cause of a lack of precipitation may be due to one or more factors, including