Blizzard

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Template:For Template:For Image:Blizzard.jpg Image:Train stuck in snow.jpg A blizzard is a severe winter storm condition characterized by low temperatures, strong winds, and heavy snow.

Contents

Definitions

Because blizzards come with the factors involving classification of winter storms are complex,there are many different definitions of blizzard. A major consensus is that in order to be classified as a blizzard, as opposed to merely a winter storm, the weather must meet several conditions. The storm must decrease visibility to a quarter of a mile or 400 meters for three consecutive hours, including snow or ice as precipitation, and have wind speeds of at least 35 miles per hour or 56 kilometres per hour (this would be seven or more on the Beaufort Wind Scale).

Another standard, according to Environment Canada, is that the winter storm must have winds of 40 km/h (25 mph) or more, have snow or blowing snow, visibility less than 1 km (about 58 mile), a wind chill of less than −25 °C (−13 °F), and all of these conditions must last for 4 hours or more, before the storm can be properly called a blizzard.

When all of these conditions persist after snow has stopped falling, meteorologists refer to the storm as a ground blizzard.

An extreme form of blizzard is a whiteout, when downdrafts coupled with snowfall become so severe that it is impossible to distinguish the ground from the air. People caught in a whiteout can quickly become disoriented, losing their sense of direction. This poses difficulty for aviation flying in the altitude of the storm.

Etymology

The word blizzard is of unknown origin, but may originate from the surname Blizzard. It was first widely used after the great United States winter storm now known as the "Blizzard of 1880."

Climatology

Severe blizzards can occur in conjunction with arctic cyclones.

Certain types of blizzards in the northeastern United States are colloquially known as Nor'easters. In the Upper Midwest, a northerly weather pattern deemed likely to produce blizzards is called an Alberta clipper.

See also

External links

da:Snestorm de:Blizzard (Wetter) fr:Blizzard (météorologie) nl:Blizzard (meteorologie) ja:地吹雪 pl:Zamieć śnieżna ru:Метель sl:Blizzard sv:Snöstorm zh:暴风雪