General Discussion

What is a blizzard?
Blizzards are dangerous winter storms that are a combination of blowing snow and wind resulting in very low visibilities. While heavy snowfalls and severe cold often accompany blizzards, they are not required. Sometimes strong winds pick up snow that has already fallen, creating a ground blizzard.

Officially, the National Weather Service defines a blizzard as a storm which contains large amounts of snow OR blowing snow, with winds in excess of 35 mph and visibilities of less than 1/4 mile for an extended period of time (at least 3 hours).

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Blizzards can create life-threatening conditions. Traveling by automobile can become difficult or even impossible due to "whiteout" conditions and drifting snow. Whiteout conditions occur most often with major storms that produce a drier, more powdery snow. In this situation, it doesn't even need to be snowing to produce whiteout conditions, as the snow which is already on the ground is blown around, reducing the visibility to near zero at times.

The strong winds and cold temperatures accompanying blizzards can combine to create another danger. The wind chill factor is the amount of cooling one "feels" due to the combination of wind and temperature. During blizzards, with the combination of cold temperatures and strong winds, very low wind chill values can occur. It is not uncommon in the Midwest to have wind chills below -60F during blizzard conditions.