Blizzards, Freezes, Ice Storms, and Hail

Factors involved: Geography, gravitational forces, ice, rain, snow, temperature, weather conditions, wind

Regions affected: Cities, coasts, deserts, forests, islands, lakes, mountains, plains, towns, valleys

Definition

Blizzards, freezes, ice storms, and hail are significant weather events that occur relatively infrequently. When they do occur, they may seriously disrupt transportation, business, and domestic activities; destroy agricultural crops; cause tens of millions of dollars in damages; and result in loss of life to humans and animals. Blizzards, freezes, and ice storms are winter storms, while hail and hailstorms occur in the warmer weather of late spring, summer, and fall.

Science

Blizzards, ice storms, and hail are significant weather events associated with dynamic interactions between masses of air. These interactions are influenced by altitude, latitude, temperature, moisture, geography, geology, cyclonic rotations, and the jet streams, as these air masses and the jet streams move from place to place.

Blizzards are severe winter storms that may occur when winds blow at a minimum of 35 miles (56 kilometers) per hour and when there is sufficient blowing or newly falling snow to reduce visibility to less than 0.25 mile (0.4 kilometer) for at least three hours. Blizzards are produced by strong frontal cyclones that bring low temperatures and blowing snow. Blizzards in the Arctic, Antarctic, mountainous regions, or the continental tundra may have winds that blow in excess of 100 miles (160 kilometers) per hour, with subzero temperatures creating the legendary blizzards of the polar seas and polar areas.

Blizzard snow as well as the perpetual snow cover often found on high mountaintops, even in the tropics, results from the condensation and freezing of moisture contained within air masses that are forced up and over the mountains in a process called orographic lifting. Snow may also form when mid-Atlantic cyclones and upper-air troughs move over mountainous locations.

A ground blizzard is one in which previously fallen snow is blown around by strong winds, often accumulating in large snow drifts that may exceed 10 feet (3 meters) in height. A whiteout is an especially dangerous type of blizzard in which visibility may be reduced to the point where the horizon, one’s surroundings, and the sky become indistinguishable. During such blizzards, exposed humans and animals often suffer from disorientation and loss of the sense of direction.

There are several meteorological mechanisms that produce snow, potentially resulting in blizzards. There must be a constant inflow of moisture to feed growing ice crystals within appropriate clouds in the upper atmosphere. Convection may lift some of the moisture to higher, cooler regions of the atmosphere, where condensation may produce snow—or rain that will become snow—as it falls through cold atmospheric regions. Ice crystals falling from higher clouds may “seed” lower clouds, resulting in snowfall. Polar air masses from the north pick up significant quantities of moisture when they blow across relatively warmer bodies of water, such as the Great Lakes. This moisture may then dissipate into huge volumes of snow downwind, on land, creating blizzards. The Pacific Ocean is the source of moisture for most snowfalls and blizzards west of the Rocky Mountains; the Gulf of Mexico and the tropical portion of the north Atlantic Ocean are generally the sources of moisture for snowfalls and blizzards in the central and eastern portions of the United States and Canada.

When deep low-pressure systems (hurricanes) form over the eastern United States and approach the Atlantic Ocean, they can grow explosively as they are moving offshore, parallel to the coastline. Because winds around a hurricane generally blow in a counterclockwise direction, snow or rain, or both, will be accompanied by strong northeast winds, creating in winter a type of blizzard known as a nor’easter. In summer the same systems can bring torrential rains, which may last for many days. Most major snowstorms and blizzards of the mid-Atlantic and New England states come from nor’easters. If the system as it moves parallel to the coast should move slowly, or stall completely, the affected land areas may be battered for hours—or even days—by blizzard conditions and large amounts of snow or rain.

Ice storms are among the most destructive of all winter storms. They are caused by rain falling from an above-freezing layer of upper air to a layer of below-freezing air on or near the earth’s surface. The freezing rain coats everything with a layer of ice, called glaze. If the rain continues to fall, and continues to freeze, staggering amounts of ice may build up on roads, bridges, trees, utility poles, transmission towers, power lines, and buildings. The ice may vary in thickness from 0.25 inch (0.6 centimeter) to as much as 6 inches (15 centimeters). Upon slight warming by the sun, ice on superstructures of bridges, buildings, power lines, and trees may loosen and fall in chunks or very large pieces known as ice slabs. This falling ice threatens the safety of anyone or anything below. Roads and bridges are generally closed when this danger exists. Ice storms cripple all modes of transportation, cause roadways and other thoroughfares to be closed, and create extremely hazardous conditions for humans and animals. Ice storms are also responsible for widespread power outages by snapping power lines and utility poles, either from the weight of the ice itself or from falling trees and branches.

Hail is sometimes confused with sleet; they are not the same thing. Sleet is made of frozen raindrops that fall during winter storms. Hail is composed of balls of ice of varying shapes and sizes that fall from the interior of cumulonimbus clouds during thunderstorms. Thunderstorms are necessary for the production of hail. Atmospheric instability associated with thunderstorms creates the powerful updrafts and downdrafts necessary for the production of hail. Hail and hailstorms occur not during the winter but rather during the late spring, summer, and fall. During these seasons, heating of the earth’s surface by the sun creates warm, rising air currents called thermals or updrafts, in a process called convection. The rising air masses contain moisture, salt particles from ocean spray, particles of kaolinite clay, volcanic dust, sulfur oxides, and other kinds of particles, which are collectively called aerosols.

As the rising air masses encounter the lower temperatures of the upper atmosphere, the moisture condenses, forming cumulonimbus clouds. Within these clouds are residual moisture present in a liquid, supercooled state; ice crystals; and aerosols. Supercooled water is water that remains in a liquid state at temperatures below which it would usually freeze. The name cumulonimbus means “heaped cloud which may produce precipitation.” These clouds, also called thunderheads, are towering, often extending vertically thousands of feet into the atmosphere. To the observer on earth they often appear puffy and lumpy and, because of upper-level wind shear, develop anvil-shaped tops. Their undersides often look dark and foreboding. Cumulonimbi are the clouds of greatest vertical extent, often measuring 10 miles (16 kilometers) or more from top to bottom.

Drops of atmospheric moisture brought by updrafts into the cold interiors of cumulonimbus clouds become supercooled and may begin to coalesce with and freeze around existing ice crystals or aerosols. Ice tends to freeze around particulate matter or other ice crystals, both of which serve as freezing nuclei, or nucleating agents. A nucleating agent is a substance that catalyzes the freezing of supercooled water into ice. Aerosols serve as nucleating agents. Updrafts within the clouds may lift the newly formed ice pellets to higher, cooler levels containing more supercooled water, which freezes them further, making them larger and heavier. When they are heavy enough for their movement to overcome the strength of the updraft, and the downward acceleration of gravity becomes the predominant force, they fall out of a cloud as hailstones. Downdrafts within a cloud may also push hailstones out and downward. Prior to exiting a cloud, hail may be bounced in trampoline fashion up and down within a cloud by competing updrafts and downdrafts. With each ascent, more supercooled water may freeze onto the ice pellets, making them still larger and heavier. Hailstones freeze in layers that look much like those of an onion. An examination of a cut hailstone shows these concentric layers. The number of layers provides a record of the number of times the hailstone was tossed up and down within the parent cloud. Hail may pass through several developmental stages and appear in pea-sized pieces called graupel, or soft hail. Hailstones may also be the size of baseballs or grapefruit.

The most frequent time for the production of hail is in the late afternoon, times that correspond to the period of maximum heating of the earth’s surface by the sun. The development of the largest hailstones requires powerful updraft velocities and many trips up and down within a cloud. The largest documented hailstone in the United States in terms of weight fell in Vivian, South Dakota, in July 2010. It had a circumference of 18.5 inches (47 centimeters) and weighed 1.9375 pounds (0.879 kilograms). An updraft velocity of almost 400 miles per hour would be required to create a hailstone that size. In the United States, weather observers and reporters report hailstone sizes either in inches or in descriptive terms such as “quarter” (1 inch, or 2.5 centimeters), “chicken egg” (2 inches, or 5 centimeters), and “softball” (4.5 inches, or 11.4 centimeters).

No one knows the maximum potential size of a hailstone. There are undocumented reports of basketball-sized hail having fallen in Manhattan, Illinois. Downdrafts from clouds may be powerful enough to slam the surface of the earth with wind gusts that exceed hurricane force, damaging property and causing airplane crashes. Powerful downdrafts are called microbursts. The amount of hail produced at any one time can be staggering. There are confirmed records of hail accumulations several feet deep, covering many square miles. It is not uncommon for snowplows to be used during the summer to clear haildrifts from roads. Melting hail is responsible for stream flooding and extensive property damage in many areas subject to hailstorms.

There are periodic reports of falling hail containing unusual items such as toads, frogs, snakes, worms, peaches and other fruits, fish, and even ducks. An explanation for such events suggests that powerful updrafts in appropriate places could be strong enough to sweep up and convectively transfer these objects from the surface of the earth into cumulonimbus clouds, where they would be coated and recoated with ice prior to falling to earth.

Geography

Blizzards occur in regions where there is an abundance of moisture that can be transformed into snow and where temperatures are low enough to both encourage snow production and sustain falling or previously fallen snow. Additionally, blizzard-prone areas are affected by jet-stream-accompanied cyclonic events, such as cyclonic vorticity, troughs, and severe frontal cyclones, which may develop in conjunction with jet streams, causing higher-than-usual winds. These systems create storms at other times of the year; however, during winter months they result in heavy snowfall and other blizzard conditions. Blizzards occur most often in Canada, the northeastern US plains states, the mid- and north Atlantic states, and downwind of the Great Lakes. Blizzards also occur in polar areas and at high altitudes at or near the summits of mountains, particularly in north, central, eastern, and western Europe.

Ice storms generally occur in a broad belt stretching from Nebraska, Oklahoma, and Kansas eastward into the mid-Atlantic and northeastern states. They can occur in any other places that experience winter weather. Ice storms are among the most devastating and deadly of all winter storms. A 1952 ice storm covered Louisiana, Arkansas, and Mississippi. It lasted from January 28 to February 4 and killed at least twenty-two people. During such storms an icy glaze of varying thickness coats all exposed surfaces and objects. During a November 1940 storm in northeastern Texas, ice coatings of 6 inches (15.2 centimeters) and more were reported. Coatings 6 inches thick were also reported in a December 1942 storm in New York State.

In February 1994, an ice storm in the southeastern United States caused nine fatalities and more than $3 billion in economic damages. During that same storm, up to 4 inches (10 centimeters) of ice accumulated in some locations from Texas to North Carolina. Some utility customers were without power for a month; coping with lengthy power outages may create serious, life-threatening situations for the elderly, the very young, and the ill. An April 1995 ice storm in Chicago resulted in the closing of Michigan Avenue, a main thoroughfare, because of great ice slabs falling from buildings and other high-rise structures. The 1998 North American ice storm, which lasted from January 4 to 10, caused thirty-five deaths, approximately $6 billion in damages, and power outages for millions of people in the northeastern United States and eastern Canada.

Ice storms also cause trees to become overburdened with the weight of the ice, causing them to collapse onto power lines or other structures. When utility poles, transmission towers, and other such structures collapse because of accumulations of ice on trees, the fallen trees and utility poles and similar structures must be removed before any work on restoring power can begin. Lack of power seriously interferes with or shuts down computers, elevators, escalators, heating systems, and hospital operations, among other things. Freezing rain and ice storms occur an average of twelve days per year around the Great Lakes and the northeastern United States. Such storms also occur in Canada and Europe.

Almost 5,000 hailstorms strike the United States each year, with perhaps 500 to 700 of them producing hailstones large enough to cause damage and injury. Hail forms in thunderstorms, but not all thunderstorms produce hail. The state of Florida has the greatest annual number of thunderstorms but has the lowest hail rate in the United States. Hail is most frequently found in “Hail Alley,” a region that covers parts of eastern Colorado, Nebraska, and Wyoming. Hail is also common in the high plains, the Midwest, and the Ohio Valley. Cheyenne, Wyoming, is the so-called US hail capital. The Pacific shorelines of the United States have the least hail. Hail in that region is produced by thunderstorms that blow on shore during winter storms. Northern India has the greatest frequency of large hail events. India also has the greatest number of human fatalities from hail. Hail belts around the world are generally found at mid-latitudes, downwind of large mountain ranges.

Hail occurs in Canada, central Europe, the Himalayan region, southern China, Argentina, South Africa, and parts of Australia. The highest documented frequency of hailfalls on earth has been in Keriche, Kenya, which averages more than 132 days of hail per year.

Prevention and Preparations

Humans cannot prevent blizzards, ice storms, or hail. In 1948 the work of scientist Vincent Schaefer showed that adding finely divided dry ice crystals to cold clouds could induce precipitation. Further studies showed that, in addition to dry ice, crystals of either silver iodide or sodium chloride added to appropriate clouds would also spur precipitation. Each of these techniques was used in major efforts to suppress hail formation and/or modify the storm-producing potential of clouds. However, much of this work was terminated because of the lack of consistent positive results. Some states, from Texas to North Dakota, would continue modest efforts to control hail production, funded by the states themselves or jointly with federal agencies.

There are several steps that may be taken to lessen damage, injury, and loss of life from blizzards, ice storms, and hail. A common response by many people to impending severe weather is to ignore it or assume that they will not be directly affected. This attitude should be replaced with one of greater respect and appreciation for these winter events, which can kill and cause hundreds of millions of dollars in damages. Information and forecasts about impending severe weather events for any area are readily available, well publicized, and continuously updated by radio, television, and online weather services. These events often last for considerable periods of time, cause power outages, and make local or long-distance travel extremely dangerous or impossible. For these reasons, prior to the onset of severe weather one should ensure that sufficient food, medical supplies, auxiliary lighting devices, water, snow shovels, and ice-melting aids are on hand. Automobiles should be fueled and should contain emergency items, even though travel or driving within or through the impacted areas should be avoided.

The occurrence of blizzards, ice storms, and hail is often unpredictable. Before the onset of such weather, one should be certain that insurance policies are in place to cover damages to personal property, agricultural produce, and livestock. Anyone caught outdoors during such events should seek immediate shelter. If one is trapped within an automobile, the chance of survival is increased by remaining with the vehicle, unless a safe place is visible outside. One should keep hazard lights on, make certain of adequate ventilation within the automobile, and make certain that snow or ice does not clog the exhaust pipe.

Mountain climbers and skiers often protect themselves from violent blizzards by digging holes in the snow, crawling in, and curling up in a fetal position to conserve body warmth. Snow is an excellent insulator. There can be a temperature difference of as much as 50 degrees 7 inches below the surface of the snow.

Rescue and Relief Efforts

Severe blizzards, ice storms, and hail may arise suddenly and be significantly more violent, extensive, or involved than previously forecast. Blizzards are often accompanied by freezing rain, hail, and sleet. During such events, humans, domestic animals, and livestock may be trapped away from adequate, safe environments and may require rescue and relief efforts from outside sources. Except for cases of the direst emergencies, rescue and relief efforts are generally mounted after the severe weather has subsided. Typical problems encountered during the storms are blocked, impassable roads and sidewalks; power outages; children, the elderly, and sick persons trapped in unheated dwellings; and travelers trapped in vehicles.

Most municipalities located within winter storm belts have dedicated public officials assigned to coordinate snow, ice, and hail removal and rescue efforts. Law enforcement agencies maintain law and order and prevent looting. Service organizations such as the American Red Cross and Salvation Army often have representatives available to assist in providing food, clothing, and shelter for those suffering from the effects of winter storms. When storm effects are very widespread, state governors may request that the president of the United States declare a state of emergency in the affected area, making people and businesses in that area eligible for federal disaster relief funds. The National Guard is frequently called upon to aid travelers and others who face peril from blizzards and other severe winter storms. The Guard helps to maintain order and prevent looting. It also combats accumulations of snow, ice, and hail.

A 1979 blizzard that dropped more than 18 inches of snow in Cheyenne, Wyoming, and Denver, Colorado, moved eastward at a time when many people were traveling for Thanksgiving. The blizzard killed 125 people, and the National Guard rescued more than 2,000 travelers. Many were rescued by helicopter, while others were stranded in automobiles, hotels, motels, National Guard armories, and public buildings and auditoriums. An Ohio blizzard in January 1978 stranded about 6,000 motorists. A state of emergency was declared, and the National Guard moved in to aid stranded motorists and exhausted utility repairpersons.

The most common hazards associated with severe winter storms are hypothermia, frostbite, broken bones, concussion, and other injuries caused by slips, falls, and vehicle accidents. Each year thousands of Americans, especially the elderly, motorists, and hikers, die from exposure to cold. Although relatively uncommon, concussive injuries from falling hail are sometimes reported. In July 1979 at Fort Collins, Colorado, an infant was killed in his mother’s arms as she tried to shield him from falling hail. A 1953 hailstorm in Alberta, Canada, killed 65,000 ducks. Rescue and relief efforts must be directed not only toward humans but also toward livestock and other animals. Failure to do so may result in staggering losses.

Impact

Blizzards, ice storms, and hail cause hundreds of millions of dollars in damages; they also kill and injure hundreds of people each year. These storms can bring big-city traffic to a complete standstill, ground airplanes, make it difficult or impossible to get to or from work or school, and create power outages and food and fuel shortages. Additional hardships may result from heavy rains and flooding that often follow such storms. The impact on traffic is enormous. More than 85 percent of all ice storm deaths result from traffic accidents.

Historical Overview

Throughout history, including modern times, blizzards and ice storms have been a serious threat to travelers. Travelers crossing the Alps have been trapped by sudden and unexpected snowstorms; this was the likely cause of death of a prehistoric man whose well-preserved remains were unearthed in the high Alps in the 1990s. The famous St. Bernard dogs, trained by the friars of the hospice founded around 982 CE by St. Bernard of Menthon, have rescued many travelers trapped in the mountain passes of Switzerland by sudden and unexpected snowstorms.

In the early fall of 1846, an unexpectedly early snowstorm in the Sierra Nevada trapped the Donner Party, a group of emigrants from the East seeking to reach California. The early storm was followed by many additional snowfalls, leading to the deaths of most of the members of the party. Some were believed to have resorted to cannibalism to relieve their hunger in the weeks immediately preceding their own deaths from starvation.

In the seventeenth century, Europe experienced what has been described as the most severe winters after the end of the Ice Age, particularly in the years 1643 to 1653. In the eighteenth century, severe weather played its part in initiating the French Revolution: A hailstorm damaged much of France’s wheat crop in the summer of 1788, sparking strong inflation in the price of bread and rousing the anger of the working class.

Hailstorms occur mostly in the summertime as a result of unusual temperature inversions, and the threat they usually pose is the destruction of agricultural crops. The growth of major transportation capabilities has enabled the world to alleviate the risks of local starvation caused by such storms, but they can be devastating to local economies, particularly in parts of the world where the standard of living is low.

The nineteenth century experienced a period of lower average temperatures in winter that led to some startling developments. The lower temperatures and early frosts are believed to have played a part in the decline of agriculture in the Northeast. As evidence of the lower temperatures, the East River in New York City froze over in January 1867. People used sleds for winter travel, and the frozen rivers and ponds provided ice that was cut, stored, and shipped south in the spring and summer in an era before mechanical refrigeration developed in the 1870s. The most striking event associated with this period of lower temperatures was the Great Blizzard of 1888, in which more than 400 people died as a result of being trapped outside or in unheated buildings. All travel came to a halt for several days.

Nevertheless, modern technology enticed several adventurers to believe they could overcome the enormous risks involved in exploring the world’s coldest continent, Antarctica. Although a Norwegian explorer, Roald Amundsen, had managed to travel overland to the South Pole and return safely in 1911, the following year another explorer of the Antarctic, Robert Falcon Scott, together with four companions, who managed to reach the South Pole a month after Amundsen, lost his life in a series of blizzards encountered on the return trip from the South Pole. People continuing a series of scientific expeditions and scientific observations carried out in Antarctica have due regard for the risks of winter weather.

In the middle of the twentieth century, colder weather hit the Northern Hemisphere, resulting in several blizzards of note. In February 1962, a major storm centered in Germany led to the deaths of 343 people. Four years later, in January 1966, the worst blizzard in seventy years struck the eastern United States. In 1972 the world's worst blizzard in recorded history occurred in Iran, a country whose climate normally does not experience such events except in the mountains to the north and east. Some 4,000 people were killed in the storm, which dropped 26 feet of snow in the southern region and ten feet in the north and central regions.

The development of predictive capabilities helped significantly to reduce the toll of such life-threatening storms. In 1960, the deployment of the first weather satellite made it possible to monitor the weather over large areas of the globe. These images enabled weather services all over the world to see major snowstorms and blizzards coming, and to alert travelers to the risks of travel and to give people time to make preparations at home. In 1967, the National Oceanographic and Atmospheric Administration (NOAA) began making public its maps of snow and ice cover all over the world. These maps later revealed that in the early 1970s the snow and ice cover had begun to grow, and by 1973 it exceeded by 11 percent its extent in 1970.

Scientists began learning about the earth’s climate and weather from the ice cores extracted from Greenland glaciers as early as 1966. These were analyzed by Danish scientists, as well as climatologists from other countries, and revealed that snowfall has been a variable event throughout history. It is concentrated, however, at high latitudes and high elevations. The lower temperatures that occurred in late medieval times, for example, wiped out the Norse settlers who had established a colony in Greenland around 1,000 CE. Thanks to ice cores, scientists now have a clear chronological picture of snowfall over the entire period since the end of the last ice age, some twelve thousand years ago.

Between 1978 and 1980, the United States was hit by a series of blizzards. The Midwest was blanketed in late January 1978, and in early February of that year the northeastern part of the country was targeted by a blizzard that saw a record-breaking 27.1 inches (69 centimeters) fall on Boston, Massachusetts. There was another blizzard in the Midwest the following January, and in February of 1979 more than 18 inches (46 centimeters) of snow piled up in the District of Columbia, bringing traffic to a halt. Washington, DC, had not received that much snow since 1922, when a blizzard known as the Knickerbocker stormdropped 28 inches of snow and killed ninety-eight people at the Knickerbocker Theatre, which collapsed. In March 1980, the mid-Atlantic region was the victim of a blizzard. Twenty-eight inches (71 centimeters) of snow fell in the Tidewater region of Virginia, more than at any time in the preceding eighty-seven years. In April, three feet (91 centimeters) of snow fell in Colorado and Utah. The same storm became a blizzard in New England. Another year of heavy snowfall was 1984. In March, much of the East Coast was hit by heavy snows, leading to eight deaths. The great popularity of skiing for recreation put many people at risk in these storms.

In January 1985, a blizzard hit the Midwest, reaching as far south as San Antonio, Texas, which had a record snowfall of 13.5 inches (34 centimeters). In November and again in December the Midwest experienced a series of blizzards, leading to thirty-three deaths. In 1986, it was Europe’s turn. In the last week in January deep cold and snow caused many rivers and canals to freeze, and thirty-three people died. In January 1992, an unusual snowstorm hit the Middle East, where it rarely snows except in the mountains. Jerusalem received as much as 18 inches (46 centimeters) of snow; 2 feet (61 centimeters) of snow fell in Amman, Jordan. In 1993 winds of 109 miles (175 kilometers) per hour (the Weather Service defines a blizzard as a snowstorm in which winds exceed 35 miles or 56 kilometers per hour) powered a blizzard, known as the Storm of the Century, along the entire East Coast, from Florida to Maine. The storm caused 213 deaths.

In 1996, a snowstorm covered much of the East Coast, and many highways were closed for as much as two days. Seventeen inches of snow fell on the District of Columbia, and the federal government shut down for two days. Parts of Pennsylvania received 31 inches (79 centimeters) of snow in this storm, and a few areas in New Jersey were blanketed by up to 37 inches (94 centimeters) of snow. The elevated trains in New York City had to shut down for a time.

On April 1 of the following year, what became known as the April Fool’s snowstorm hit the Northeast. A sudden change in the path of this storm caught weather predictors by surprise. In May 1996, twelve climbers on Mount Everest perished in a blizzard as they neared the peak of the mountain. The severe weather of 1996–97 also proved fatal to at least 240 Hindu pilgrims attempting a pilgrimage to a cave in Kashmir; they were caught in a freak snowstorm on August 25, 1996.

What was termed a once-in-a-century ice storm devastated much of the Northeast as well as eastern Canada between January 5 and January 12, 1998. The storm dragged down power lines in much of the region, and crews had to be imported from southern states to help repair the damage. Many residents were without power for several weeks. The ice storm of 1998 was described as the most destructive storm in Canadian history. The Adirondacks in New York, as well as northern Vermont, New Hampshire, and Maine, were also hit. Damages in Canada exceeded a half billion dollars, and insurance claims totaling more than $1 billion were filed in both countries. Seven people died in Maine as a result of this storm and four in New York State.

The threat posed by snow and ice was transferred to Europe in the early months of 1999. Heavy snows in the Alps in February and March, the heaviest in fifty years, triggered avalanches that trapped a number of skiers and other tourists. At least thirty-one people died in Austria and eighteen in France. In February 2008, a powerful blizzard and freezing temperatures in central and western Afghanistan killed more than nine hundred people and tens of thousands livestock.

In February 2010, three record-setting blizzards struck the United States. On February 5–6, the storm which became known as Snowmageddon or Snowpocalypse struck the Mid-Atlantic states and dropped record-setting snowfall. The Blizzard of 2010 struck the East Coast from Washington, DC, to Boston, on February 9. Then, on February 25, the Northeast was hit once more by a storm that caused widespread power outages.

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