Blizzard
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This article is about the winter storm condition. For other uses, see Blizzard (disambiguation).
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Downburst · Lightning
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Extratropical cyclone
Winter storm · Blizzard · Ice storm
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Drizzle · Rain · Snow · Graupel
Freezing rain · Ice pellets · Hail
A blizzard is a severe storm condition characterized by low temperatures, strong winds, and can include heavy snow. By definition, the difference between blizzard and a snowstorm is the strength of the wind. To be a blizzard, a snow storm must have winds in excess of 56 km/h (35 mph).[1] Additionally, blizzards must reduce visibility to 400 metres (1,300 ft) or less and must last for a prolonged period of time — typically three hours or more.[2][3] Ground blizzards are a variation on the traditional blizzard, in that ground blizzards require high winds to stir up snow that has already fallen, rather than fresh snowfall. Regardless of the variety of blizzard, they can bring near-whiteout conditions, which restrict visibility to near zero. Blizzards have a negative impact on local economies and can paralyze regions for days at a time, particularly where snowfall is unusual or rare.
The differences from a whiteout
Although the word "blizzard" is commonly used to describe heavy snow and high winds, a blizzard should not be called a "whiteout". Whiteout occurs mostly in the Arctic and Antarctic during the spring, when snow is still deep on the ground and there is lots of daylight, surprisingly calm weather and excellent visibility. Whiteout occurs when rays of sunlight are bounced in all directions between bright white clouds, especially a thin layer of overcast, and bright snow or ice. Clean snow and ice reflects nearly 85% of incoming light. Falling snowflakes, suspended fog droplets or ice particles in the air would make conditions even worse. In a whiteout, neither shadows, nearby objects, landmarks, nor clouds are discernible. For people experiencing a whiteout, their sense of direction, depth perception and even their balance may be lost. Land and sky seem to blend, and the horizon disappears into a white nothingness. Whiteouts trick pilots and travelers into believing down is up and far is near.
Economic impact of blizzards
Like all severe weather events such as hurricanes, droughts, and floods, blizzards can be disruptive to local economies and likely have a significant impact on society. This is especially the case when blizzards hit in localities in generally warmer climates where snowfall is infrequent. In cities that do not have snow removal equipment, traffic and commerce can be brought to a standstill for days and in some cases weeks. The economic impacts include lost productivity because people cannot get to work or parents must stay home with children due to school closings, airport closures, product delivery delays and the cost of snow removal.