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Winter Storms & Blizzards! What they are and what they aren’t

Definition

• A blizzard is a severe winter storm condition characterized by low temperatures, strong winds, and heavy blowing snow.

• The term blizzard is sometimes misused by news media to describe a large winter storm that does not actually satisfy official blizzard criteria.

Where they occur • Even though some areas are more likely

to experience blizzards than others, it is possible for a blizzard to occur in any location where there are snow falls and high winds.

• In North America, blizzards are particularly common to the extreme portions of the Northeastern United States, the Northern Great Plains in the United States, Atlantic Canada, and the Canadian Prairie Provinces.

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Technical Definition

In the United States, the National Weather Service defines a blizzard as sustained 35 mph winds which leads to blowing snow and causes visibilities of ¼ mile or less, lasting for at least 4 hours. Extremely cold temperatures with a wind chill of less than −25 °C

Whiteouts

• 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.

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Where does the word come from?

• The Word 'Blizzard' was first used in 1870 during a severe snowstorm in Iowa and Minnesota, by an Estherville, Iowa newspaper. The word has its origins in boxing, referring to a volley of punches in Boxing. The word was first used by the USA signal corps weather service in 1876.

Great Blizzard of 1888

• The Great Blizzard of 1888 paralyzed the Northeastern United States. In that blizzard, 400 people were killed, 200 ships were sunk, and snowdrifts towered 15 to 50 feet high.

• Earlier that year, the Great Plains states were struck by the Schoolhouse Blizzard that left children trapped in schoolhouses and killed 235 people.

The Great Blizzard of '49

• The worst blizzard the U.S. has ever known. This famous blizzard also known as the "Great White Death" was actually a series of blizzards that lasted for seven weeks. They began in Wyoming and Colorado, then spread over most of the West. To save cattle and sheep, the U.S. Air Force dropped 1,500 tons of hay. More than 100 people and 1 million heads of livestock were killed in this deadly blizzard.

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How does it form?

Warm air must rise over cold air. Wind can either pull cold air from the poles to the equator or wind pulls warm air

from the equator to the poles. The two air masses of different temperatures forms a front. Cold air at the surface, lots of moisture, and lift of warm air over cold air masses forms long-lasting blizzards with very strong winds and intense snowfall!!

How does it form?

Cold air moves over warm water and is warmed from below. Moisture evaporates in the air.

Warm moist air rises downwind of lakes and forms heavy snow.

Advisory, Watches & Warnings

• WINTER WEATHER ADVISORIES

– Issued for accumulations of snow, freezing

rain, freezing drizzle, and sleet; could lead to life-threatening situations.

• WINTER STORM WATCH

– possibility of a blizzard, heavy snow, heavy freezing rain, or heavy sleet within the next 12 to 48 hours.

• WINTER STORM WARNING

– hazardous winter weather in the form of heavy snow, heavy freezing rain, or heavy

sleet within the next 12 to 24 hours.

Advisory, Watches & Warnings

• BLIZZARD WARNING

– sustained or gusty winds of 35 mph or more, and

falling or blowing snow creating visibilities at or below 1/4 mile; conditions should persist for 3 hours.

• WIND CHILL ADVISORY

– Issued when the wind chill temperature is forecast to be between -15°F to -24°F.

• WIND CHILL WARNING

– Issued when the wind chill temperature is forecast to be -25°F or lower.

Winter Storm Safety Tips BEFORE A WINTER STORM: Have a disaster plan Prepare a disaster supplies kit for your home and car

Include a first aid kit, emergency food supply, bottled water, battery-operated radio, flashlight, protective clothing, and blankets.

DURING A WINTER STORM: Stay indoors and dress warmly. Eat regularly and

drink lots of water. If you must go outside, wear layered clothing,

mittens and a hat. Watch for signs of hypothermia and frostbite.

AFTER A WINTER STORM: Avoid driving until conditions have improved. Avoid overexertion! Heart attacks from shoveling

snow are the leading cause of deaths during the winter.

Check on your neighbors to make sure they are okay.

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BLIZZARD Safety To protect themselves when blizzards are forecast, people should have a checklist of things they need to do. On it should be:

• Fill bathtubs with water in case pipes freeze.

• Make sure windows and doors are tightly closed and anything movable in the yard is tied down or brought inside. Bring in pets too!

• Be sure to stock up on food, especially food that doesn't need to be cooked, refrigerated, or frozen.

• Have batteries for flashlights and radios. Unless it is necessary stay indoors.

Snow fact

•Did you know that it's never too cold to snow? Snow can occur at any time when the temperature is near or below freezing.