Blizzards are caused when warm air collides with very cold air. For a blizzard to form, the air temperature should be near or below the freezing point of water. A blizzard has sustained wind speeds of 35 miles per hour or more and lasts more than three hours.
A blizzard is experienced in the higher latitudes where cold winds from the poles moves south and warm winds from the tropics moves north. Sometimes it may not snow during a blizzard but the snow on the ground is whipped up by sustained winds leading to poor visibility and life threatening conditions. The visibility drops to less than 400 meters during a blizzard and this can lead to road accidents.
Frost bite, breathing difficulties and hypothermia can occur very easily if caught unprotected in a blizzard. Skin exposed to such severely cold condition can lose all sensitivity within minutes.
Blizzards that last a long time can wreak havoc on life and property. Traffic and communication is severely disrupted. Power lines can collapse under the weight and power of the wind and snow. Food and water shortage can result if the blizzard is sustained over a long duration. Medical emergencies are very difficult to attend to during a blizzard.
Extremely low temperatures have an effect on plant life too.