A blizzard is a severe snowstorm characterized by strong sustained winds and low visibility, lasting for a prolonged period of time—typically at least three or four hours. A ground blizzard is a weather condition where snow that has already fallen is being blown by wind. Blizzards can have an immense size and usually stretch to hundreds or thousands of kilometres.
Snow comprises individual ice crystals that grow while suspended in the atmosphere—usually within clouds—and then fall, accumulating on the ground where they undergo further changes. It consists of frozen crystalline water throughout its life cycle, starting when, under suitable conditions, the ice crystals form in the atmosphere, increase to millimeter size, precipitate and accumulate on surfaces, then metamorphose in place, and ultimately melt, slide or sublimate away.
Lake-effect snow is produced during cooler atmospheric conditions when a cold air mass moves across long expanses of warmer lake water. The lower layer of air, heated by the lake water, picks up water vapor from the lake and rises through colder air. The vapor then freezes and is deposited on the leeward (downwind) shores.
A winter storm is an event in which wind coincides with varieties of precipitation that only occur at freezing temperatures, such as snow, mixed snow and rain, or freezing rain. In temperate continental and subarctic climates, these storms are not necessarily restricted to the winter season, but may occur in the late autumn and early spring as well. A snowstorm with strong winds and low visibility is called a blizzard.
Sastrugi, or zastrugi, are features formed by the erosion of snow by wind. They are found in polar regions, and in snowy, wind-swept areas of temperate regions, such as frozen lakes or mountain ridges. Sastrugi are distinguished by upwind-facing points, resembling anvils, which move downwind as the surface erodes. These points usually lie along ridges parallel to the prevailing wind; they are steep on the windward side and sloping to the leeward side. Smaller irregularities of this type are known as ripples or wind ridges.
Orographic lift occurs when an air mass is forced from a low elevation to a higher elevation as it moves over rising terrain. As the air mass gains altitude it quickly cools down adiabatically, which can raise the relative humidity to 100% and create clouds and, under the right conditions, precipitation.
The Northeastern United States blizzard of 1978 was a catastrophic, historic nor'easter that struck New England, New Jersey, Pennsylvania, and the New York metropolitan area. The Blizzard of '78 formed on Sunday, February 5, 1978 and broke up on February 7. The storm was initially known as "Storm Larry" in Connecticut, following the local convention promoted by the Travelers Weather Service on television and radio stations there. Snow fell mostly from Monday morning, February 6 to the evening of Tuesday, February 7. Connecticut, Rhode Island, and Massachusetts were hit especially hard by this storm.
The Great Blizzard of 1888, also known as the Great Blizzard of '88 or the Great White Hurricane, was one of the most severe recorded blizzards in American history. The storm paralyzed the East Coast from the Chesapeake Bay to Maine, as well as the Atlantic provinces of Canada. Snow fell from 10 to 58 inches in parts of New Jersey, New York, Massachusetts, Rhode Island, and Connecticut, and sustained winds of more than 45 miles per hour (72 km/h) produced snowdrifts in excess of 50 feet (15 m). Railroads were shut down and people were confined to their homes for up to a week. Railway and telegraph lines were disabled, and this provided the impetus to move these pieces of infrastructure underground. Emergency services were also affected during this blizzard.
The blizzard of 1977 hit Western New York, Central NY, Northern NY, and Southern Ontario from January 28 to February 1 of that year. Daily peak wind gusts ranging from 46 to 69 mph were recorded by the National Weather Service in Buffalo, with snowfall as high as 100 in (254 cm) recorded in areas, and the high winds blew this into drifts of 30 to 40 ft. There were 23 total storm-related deaths in Western New York, with five more in northern New York.
The 1993 Storm of the Century was a cyclonic storm, or nor'easter, that formed over the Gulf of Mexico on March 12, 1993. The cold weather, heavy snowfall, high winds and storm surges that the storm brought affected a very large area; at its height, it stretched from Canada to Honduras. The cyclone moved through the Gulf of Mexico and then through the eastern United States before moving on to eastern Canada. It eventually dissipated in the North Atlantic Ocean on March 15.
Rime ice forms when supercooled water droplets freeze onto surfaces. In the atmosphere, there are three basic types of rime ice:
A snow fence, similar to a sand fence, is a barrier that forces windblown, drifting snow to accumulate in a desired place. They are employed primarily to minimize the amount of snowdrift on roadways and railways. Farmers and ranchers use snow fences to create drifts in basins for a ready supply of water in the spring. Ski resorts also use snow fences in order to increase snow depth in specified areas, or for avalanche control.
The Holiday Blizzards were major storms occurring in two segments during the last two weeks of December 2006 in the Denver, Colorado area. The blizzards occurred within a week of each other. A subsequent storm, narrower in scope, struck the area less than a week after the second blizzard, further hampering removal efforts and travel in the region. The blizzard covered homes.
Blowing snow is snow lifted from the surface by the wind, at eye level or more, that will reduce visibility. Blowing snow can come from falling snow or snow that already accumulated on the ground but is picked up and blown about by strong winds. It is one of the classic requirements for a blizzard. Its METAR code is BLSN. If the snow remains below 1.8 m (6 ft), it will be called drifting snow. The snow which is being blown about may deposit as snowdrifts.
The Iran blizzard of February 1972 was the deadliest blizzard in history, as recorded by the Guinness Book of Records. A week-long period of low temperatures and severe winter storms, lasting 3–9 days in February 1972, resulted in the deaths of over 4,000 people. Storms dumped more than 7.9 metres of snow across rural areas in northwestern, central and southern Iran. The blizzard came after four years of drought.
A sand fence or sandbreak, similar to a snow fence, is a barrier used to force windblown, drifting sand to accumulate in a desired place. Sand fences are employed to control erosion, help sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas. Sand fences are also commonly employed following storm events in order to aid in the dune recovery process, particularly in developed areas where dunes are critical for protection of property.
Classifications of snow describe and categorize the attributes of snow-generating weather events, including the individual crystals both in the air and on the ground, and the deposited snow pack as it changes over time. Snow can be classified by describing the weather event that is producing it, the shape of its ice crystals or flakes, how it collects on the ground, and thereafter how it changes form and composition. Depending on the status of the snow in the air or on the ground, a different classification applies.
The Chicago blizzard of 1967 struck northeast Illinois and northwest Indiana on January 26–27, 1967, with a record-setting 23 inches (58 cm) snow fall in Chicago and its suburbs before the storm abated the next morning. As of 2024, it remains the greatest snowfall in one storm in Chicago history. As the blizzard was a surprise during the day with people already at work or school, it stopped the city for a few days as people dug out. "The storm was a full-blown blizzard, with 50 mph-plus northeast wind gusts creating drifts as high as 15 feet."
The Geography of Atlanta encompasses 132.4 square miles (342.9 km2), of which 131.7 square miles (341.1 km2) is land and 0.7 square miles (1.8 km2) is water. The city is situated among the foothills of the Appalachian Mountains, and at 1,050 feet (320 m) above mean sea level, Atlanta has the highest elevation among major cities east of the Mississippi River. Atlanta straddles the Eastern Continental Divide, such that rainwater that falls on the south and east side of the divide flows into the Atlantic Ocean, while rainwater on the north and west side of the divide flows into the Gulf of Mexico. Atlanta sits atop a ridge south of the Chattahoochee River, which is part of the ACF River Basin. Located at the far northwestern edge of the city, much of the river's natural habitat is preserved, in part by the Chattahoochee River National Recreation Area.
The January 2022 North American blizzard caused widespread and disruptive impacts to the Atlantic coast of North America from northern Delaware to Nova Scotia with as much as 2.5 feet (30 in) of snowfall, blizzard conditions and coastal flooding at the end of January 2022. Forming from the energy of a strong mid- to upper-level trough, the system developed into a low-pressure area off the Southeast United States on January 28. The system then quickly intensified that night as it traveled northeast parallel to the coast on January 29, bringing heavy snowfall blown by high winds to the upper East Coast of the continent. Further north, it also moved inland in Maine and its width meant it strongly impacted all three of Canada's Maritime provinces. In some areas, mainly the coastal regions due to the wind, areas of New Jersey, Long Island and Massachusetts, it was the first blizzard since a storm in January 2018. The storm was considered a "bomb cyclone" as it rapidly intensified and barometric pressure dropped at least 24 millibars over a 24-hour period. The storm was given names such as Blizzard of 2022 and Winter Storm Kenan.
