Atmospheric hazards are the hazards that appear to be observed in the atmosphere. For example: storms, tornados, thunderstorm, hail, drought, cyclone, ozone layer depletion, greenhouse effect, global warming, acid rain and aerosol.

a. Strom: They are recognized by low pressure zones. They develop in the ocean and move towards land. As the intensity increases they may develop to form cyclone. The wind speed ranges from 55-60 kilonots.

b. Tornadoes: They are most violent and destructive storms of lower troposphere. They are rapidly rotating wind that blow around a small area of intense low pressure which extend downwards from cumulonimbus cloud. Except the extremely cold regions of the continent, during the winter and polar regions, tornadoes may develop anywhere in the world. They are common in USA and Australia.

c. Cyclone: It is an atmospheric disturbance, which involves a closed circulation about low pressure region. A cyclone has an anti clock wise direction in northern hemisphere and clockwise in southern hemisphere.

Tropical cyclone originates in the tropical zone of 5 degree to 20 degree latitude in both hemisphere. This cyclone is formed in the ocean only because oceans can supply sufficient amount of energy to its formation. For the formation of cyclone the temperature of water surface should be grater than 26 degree Celsius. This is the main reason why Nepal does not experience the tropical cyclone.

Extra tropical cyclone develops in regions lying between 30 degree and 65 degree latitude in both hemisphere. It has size of 160 km to 3200 km diameter.