Cyclone occurs in Bangladesh almost every year .They come as a natural calamity and cause great havoc. It is a short of rotator storm from the Bay of Bengal. They are attended with lighting and thunder and very often with heavy rainfall. 

In Bangladesh the first indication of the approach of a cyclone in that the sky in the north-west is covered with patches of dark cloud. Then the wind begins to blow with a moaning sound.  Soon the sound of the wind becomes as loud as booming of the cannon. 

The current of the wind is never steady and regular, but is always fitful and violent. The whole sky now looks like one dark sheet of cloud this is the sign of the imminent crisis.  Blasts of winds grow stronger and stronger. There are heavy rains, peals of thunder and flashes of lighting. At one moment there is the lull but the next moment there is the blast of greater force. 

The force of wind grows so strong that it shakes even the solid building to their foundation. This terrific state continues for hours together and sometimes it lasts for a whole day.

Almost every time the offshore islands were the hardest hit areas .On some three occasions they are attended with tidal bore. The havoc caused by this everything is beyond description. Almost everything that comes within their sweep was destroyed away.