Winter storm

Last updated

A winter storm is an event in which varieties of precipitation are formed that only occur at low temperatures, such as snow or sleet, or a rainstorm where ground temperatures are low enough to allow ice to form (i.e. freezing rain). In temperate continental climates, these storms are not necessarily restricted to the winter season, but may occur in the late autumn and early spring as well. Very rarely, they may form in summer, though it would have to be an abnormally cold summer, such as the summer of 1816 in the Northeastern United States.

Temperature physical property of matter that quantitatively expresses the common notions of hot and cold

Temperature is a physical quantity expressing hot and cold. It is measured with a thermometer calibrated in one or more temperature scales. The most commonly used scales are the Celsius scale, Fahrenheit scale, and Kelvin scale. The kelvin is the unit of temperature in the International System of Units (SI), in which temperature is one of the seven fundamental base quantities. The Kelvin scale is widely used in science and technology.

Snow precipitation in the form of flakes of crystalline water ice

Snow refers to forms of ice crystals that precipitate from the atmosphere and undergo changes on the Earth's surface. It pertains to 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. Snowstorms organize and develop by feeding on sources of atmospheric moisture and cold air. Snowflakes nucleate around particles in the atmosphere by attracting supercooled water droplets, which freeze in hexagonal-shaped crystals. Snowflakes take on a variety of shapes, basic among these are platelets, needles, columns and rime. As snow accumulates into a snowpack, it may blow into drifts. Over time, accumulated snow metamorphoses, by sintering, sublimation and freeze-thaw. Where the climate is cold enough for year-to-year accumulation, a glacier may form. Otherwise, snow typically melts seasonally, causing runoff into streams and rivers and recharging groundwater.

Ice pellets are a form of precipitation consisting of small, translucent balls of ice. Ice pellets are smaller than hailstones which form in thunderstorms rather than in winter, and are different from graupel which is made of frosty white rime, and from a mixture of rain and snow which is a slushy liquid or semisolid. Ice pellets often bounce when they hit the ground or other solid objects, and make a higher-pitched "tap" when striking objects like jackets, windshields, and dried leaves, compared to the dull splat of liquid raindrops. Pellets generally do not freeze into a solid mass unless mixed with freezing rain. The METAR code for ice pellets is PL.



Fullerton harbor looking south Chicago Feb 2 2011 storm.JPG
Chicago at Dusk in December.JPG
Chicago's Fullerton Harbor looking south during the January 31 – February 2, 2011 North American winter storm (left) and on a clear day for comparison
Approaching winter storm in Salt Lake City. SLCcloudyApril.jpg
Approaching winter storm in Salt Lake City.

Snowstorms are storms where large amounts of snow fall. Two inches (5 cm) of snow is enough to create serious disruptions to traffic and school transport (because of the difficulty to drive and maneuver the school buses on slick roads). This is particularly true in places where snowfall is not typical but heavy accumulating snowfalls can occur. In places where snowfall is typical, such small snowfalls are rarely disruptive, because of effective snow and ice removal by municipalities, increased use of four-wheel drive and snow tires, and drivers being more used to winter conditions. Snowfalls in excess of 6 inches (15 cm) are usually universally disruptive.

Traffic Road users travelling by foot or vehicle

Traffic on roads consists of road users including pedestrians, ridden or herded animals, vehicles, streetcars, buses and other conveyances, either singly or together, while using the public way for purposes of travel. Traffic laws are the laws which govern traffic and regulate vehicles, while rules of the road are both the laws and the informal rules that may have developed over time to facilitate the orderly and timely flow of traffic.

Four-wheel drive type of drivetrain with four driven wheels

Four-wheel drive, also called 4×4 or 4WD, refers to a two-axled vehicle drivetrain capable of providing torque to all of its wheels simultaneously. It may be full-time or on-demand, and is typically linked via a transfer case providing an additional output drive-shaft and, in many instances, additional gear ranges.

Snow tire

Snow tires—also called winter tires—are tires designed for use on snow and ice. Snow tires have a tread design with larger gaps than those on summer tires, increasing traction on snow and ice. Such tires that have passed a specific winter traction performance test are entitled to display a "Three-Peak Mountain Snow Flake" symbol on their sidewalls. Tires designed for winter conditions are optimized to drive at temperatures below 7 °C (45 °F). Some snow tires have metal or ceramic studs that protrude from the tire to increase traction on hard-packed snow or ice. Studs abrade dry pavement, causing dust and creating wear in the wheel path. Regulations that require the use of snow tires or permit the use of studs vary by country in Asia and Europe, and by state or province in North America.

A massive snowstorm with strong winds and other conditions meeting certain criteria is known as a blizzard. A large number of heavy snowstorms, some of which were blizzards, occurred in the United States during 1888 and 1947 as well as the early and mid-1990s. The snowfall of 1947 exceeded 2 feet (61 cm) with drifts and snow piles from plowing that reached 12 feet (3.7 m) and for months, temperatures did not rise high enough to melt the snow. The 1993 "Superstorm" manifested as a blizzard in most of the affected areas.

Blizzard type of snowstorm

A blizzard is a severe snowstorm characterized by strong sustained winds of at least 56 km/h (35 mph) and lasting for a prolonged period of time—typically three hours or more. A ground blizzard is a weather condition where snow is not falling but loose snow on the ground is lifted and blown by strong winds. Blizzards can have an immense size and usually stretch to hundreds or thousands of kilometres.

United States Federal republic in North America

The United States of America (USA), commonly known as the United States or America, is a country comprising 50 states, a federal district, five major self-governing territories, and various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is slightly smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U.S. is the third most populous country. The capital is Washington, D.C., and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico. The State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean. The U.S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The extremely diverse geography, climate, and wildlife of the United States make it one of the world's 17 megadiverse countries.

Great Blizzard of 1888 severe blizzard that hit the USA in March 1888

The Great Blizzard of 1888 or Great Blizzard of '88 was one of the most severe recorded blizzards in the history of the United States of America. The storm, referred to as the Great White Hurricane, paralyzed the East Coast from the Chesapeake Bay to Maine, as well as the Atlantic provinces of Canada. Snowfalls of 10 to 58 inches fell 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 houses 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.

Large snowstorms could be quite dangerous: a 6 in (15 cm) snowstorm will make some unplowed roads impassable, and it is possible for automobiles to get stuck in the snow. Snowstorms exceeding 12 in (30 cm) especially in southern or generally warm climates will cave the roofs of some homes and cause the loss of electricity. Standing dead trees can also be brought down by the weight of the snow, especially if it is wet or very dense. Even a few inches of dry snow can form drifts many feet high under windy conditions.

Roof covering on the uppermost part of a building or vehicle

A roof is the top covering of a building, including all materials and constructions necessary to support it on the walls of the building or on uprights; it provides protection against rain, snow, sunlight, extremes of temperature, and wind. A roof is part of the building envelope.

Dangers of snow

Accumulating snow can make driving motor vehicles very hazardous. Accumulation of snow on roadways reduces friction between tires and the pavement, which in turn lowers the maneuverability of a vehicle considerably. As a result, average driving speeds on public roads and highways are reduced by up to 40% while heavy snow is falling. [1] Visibilities are reduced by falling snow, and this is further exacerbated by strong winds which are commonly associated with winter storms producing heavy snowfall. In extreme cases, this may lead to prolonged whiteout conditions in which visibilities are reduced to only a few feet due to falling or blowing snow. These hazards can manifest even after snowfall has ended when strong winds are present, as these winds will pick up and transport fallen snow back onto roadways and reduce visibilities in the process. This can even result in blizzard conditions if winds are strong enough. [2] Heavy snowfall can immobilize a vehicle entirely, which may be deadly depending on how long it takes rescue crews to arrive. The clogging of a vehicle's tailpipe by snow may lead to carbon monoxide buildup inside the cabin. [3]

Whiteout (weather)

Whiteout is a weather condition in which visibility and contrast are severely reduced by snow, fog, or sand. The horizon disappears from view while the sky and landscape appear featureless, leaving no points of visual reference by which to navigate. Whiteout has been defined as: "A condition of diffuse light when no shadows are cast, due to a continuous white cloud layer appearing to merge with the white snow surface. No surface irregularities of the snow are visible, but a dark object may be clearly seen. There is no visible horizon."

Ground blizzard

Ground blizzard refers to a weather condition where loose snow or ice on the ground is lifted and blown by strong winds. This can occur in the absence of precipitation, and can even occur when the sky is clear. This is in contrast to "ordinary" blizzards, which are accompanied by heavy falling snow. They can be especially dangerous as they occur after a winter storm has passed, when it is assumed that all forms of severe winter weather has ended.

Carbon monoxide chemical compound

Carbon monoxide (CO) is a colorless, odorless, and tasteless flammable gas that is slightly less dense than air. It is toxic to animals that use hemoglobin as an oxygen carrier when encountered in concentrations above about 35 ppm, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere, it is spatially variable and short lived, having a role in the formation of ground-level ozone.

Depending on the temperature profile in the atmosphere, snow can be either wet or dry. Dry snow, being lighter, is transported by wind more easily and accumulates more efficiently. Wet snow is heavier due to the increased water content. Significant accumulations of heavy wet snow can cause roof damage. It also requires considerably more energy to move and this can create health problems while shoveling when combined with the harsh weather conditions. Numerous deaths as a result of heart attacks can be attributed to snow removal. [4] Accretion of wet snow to elevated surfaces occurs when snow is "sticky" enough which can cause extensive tree and power line damage in a manner similar to ice accretion during ice storms. Power can be lost for days during a major winter storm, and this usually means the loss of heating inside buildings. Other than the obvious risk of hypothermia due to cold exposure, another deadly element associated with snowstorms is carbon monoxide poisoning which can happen anytime combustion products from generators or heating appliances are not properly vented. Finally, partially or fully melted snow on roadways can refreeze when temperatures fall, creating black ice.

Carbon monoxide poisoning Toxic effects of carbon monoxide

Carbon monoxide poisoning typically occurs from breathing in carbon monoxide (CO) at excessive levels. Symptoms are often described as "flu-like" and commonly include headache, dizziness, weakness, vomiting, chest pain, and confusion. Large exposures can result in loss of consciousness, arrhythmias, seizures, or death. The classically described "cherry red skin" rarely occurs. Long term complications may include feeling tired, trouble with memory, and movement problems. In those exposed to smoke, cyanide toxicity should also be considered.

Black ice thin coating of glazed ice on a surface

Black ice, sometimes called clear ice, is a thin coating of glaze ice on a surface, especially on roads. The ice itself is not black, but visually transparent, allowing the often black road below to be seen through it. The typically low levels of noticeable ice pellets, snow, or sleet surrounding black ice means that areas of the ice are often practically invisible to drivers or people stepping on it. There is, thus, a risk of slippage and subsequent accident due to the unexpected loss of traction.

A sudden rise in air temperature is can result in the rapid melting of snow. This can create flooding issues if the snowpack has sufficient water content, and this can be significantly exacerbated by heavy rainfall and by ice jams which may have formed on area rivers during prolonged subfreezing temperatures. The re-freezing of previously melted snow creates potholes in roadways. [5] This process is accelerated when water is melted and re-frozen multiple times. Fog is also known to occur during rapid melting of snow. [6]

Avalanches and cornices occur when significant amounts of snow falls on mountains.

Freezing rain

Heavy showers of freezing rain are one of the most dangerous types of winter storm. They typically occur when a layer of warm air hovers over a region, but the ambient temperature a few meters above the ground is near or below 0 °C (32 °F), and the ground temperature is sub-freezing.

While a 10 cm (3.9 in) snowstorm is somewhat manageable by the standards of the northern United States and Canada, a comparable 10 mm (0.39 in) ice storm can paralyze a region: driving becomes extremely hazardous, telephone and power lines are damaged, and crops may be ruined. [7]

Notable ice storms include an El Niño-related North American ice storm of 1998 that affected much of eastern Canada, including Montreal and Ottawa, as well as upstate New York and part of New England. Three million people lost power, some for as long as six weeks. One-third of the trees in Montreal's Mount Royal park were damaged, as well as a large proportion of the sugar-producing maple trees. The amount of economic damage caused by the storm has been estimated at $3 billion Canadian.

The Christmas Day Ice Storm of 2000 caused devastating electrical issues in parts of Arkansas, Oklahoma, and Texas. The city of Texarkana, Arkansas experienced the worst damage, at one point losing the ability to use telephones, power and running water. In some areas in Arkansas, Oklahoma, Texas and eventually Louisiana, over an inch of ice accumulated from the freezing rain. [8] [9]

The Ice Storm of December 2002 in North Carolina resulted in massive power loss throughout much of the state, and property damage due to falling trees. Except in the mountainous western part of the state, heavy snow and icy conditions are rare in North Carolina.

The Ice Storm of December 2005 was another severe winter storm producing extensive ice damage across a large portion of the Southern United States on December 14 to 16. It led to power outages and at least 7 deaths.

In January 2005, Kansas had been declared a major disaster zone by President George W. Bush after an ice storm caused nearly $39 million in damages to thirty-two counties. Federal funds were provided to the counties during January 46, 2005 to aid the recovery process. [10]

The January 2009 Central Plains and Midwest ice storm was a crippling and historic ice storm. Most places struck by the storm, saw 2 inches (51 mm) or more of ice accumulation, and a few inches of snow on top of it. This brought down power lines, causing some people to go without power for a few days, to a few weeks. In some cases, some didn't see power for a month or more. At the height of the storm, more than 2 million people were without power.


Ice crystals fall through a cloud of super-cooled droplets—minute cloud droplets that have fallen below freezing temperature but have not frozen. The ice crystal plows into the super-cooled droplets and they immediately freeze to it. This process forms graupel, or snow pellets, as the droplet continues to accumulate on the crystal. The pellets bounce when they hit the ground.

Ice pellets

Out ahead of the passage of a warm front, falling snow may partially melt and refreeze into a frozen rain drop before it reaches the ground. These ice pellets are called sleet in most of the US. Because it is easily seen and does not accumulate ice, it is not as dangerous as freezing rain.


Rime is a milky white accumulation of super-cooled cloud or fog droplets that freeze when they strike an object that has a temperature of 32 °F (0 °C), the freezing point of water. The process is called riming when super-cooled cloud droplets attach to ice crystals in the formation of graupel. Rime ice can pose a hazard to an airliner when it forms on a wing as an aircraft flies through a cloud of super-cooled droplets.

See also

Related Research Articles

Freezing rain is the name given to rain maintained at temperatures below freezing by the ambient air mass that causes freezing on contact with surfaces. Unlike a mixture of rain and snow, ice pellets, or hail, freezing rain is made entirely of liquid droplets. The raindrops become supercooled while passing through a sub-freezing layer of air hundreds of meters above the ground, and then freeze upon impact with any surface they encounter, including the ground, trees, electrical wires, aircraft, and automobiles. The resulting ice, called glaze ice, can accumulate to a thickness of several centimeters and cover all exposed surfaces. The METAR code for freezing rain is FZRA.

A winter storm warning is a statement made by the National Weather Service of the United States which means a winter storm is occurring or is about to occur in the area, usually within 36 hours. Generally, a Winter Storm Warning is issued if the following criteria, at least, are forecast: usually between 4 inches (10 cm) to 7 inches (18 cm) or more of snow or usually 3 inches (7.6 cm) or more of snow with a large accumulation of ice. In the Southern United States, where severe winter weather is much less common and any snow is a more significant event, warning criteria are lower, as low as 1 inch (2.5 cm) in the southernmost areas: as one goes from north to south, the necessary accumulations lessen. A warning can also be issued during high impact events of lesser amounts, usually early or very late in the season when trees have leaves and damage can result. Winter Storm Warnings are issued when winds are less than 35mph; if the storm has winds above this wind speed, it becomes a blizzard warning.

North American blizzard of 1996 January 1996 blizzard in North America

The Blizzard of 1996 was a severe nor'easter that paralyzed the United States East Coast with up to 4 feet (1.2 m) of wind-driven snow from January 6 to January 8, 1996. This storm was a classic example of a nor'easter, but the storm would not have been as historically significant without the presence of the arctic high pressure system located to the north of New York. It was followed by another storm, an Alberta Clipper, on January 12, then unusually warm weather and torrential rain which caused rapid melting and river flooding. Along with the March Superstorm of 1993, it is one of only two snowstorms to receive the top rating of 5, or "Extreme", on the Northeast Snowfall Impact Scale (NESIS).

The Northeast Snowfall Impact Scale (NESIS) was created to measure snowstorms in the U.S. Northeast in much the same way the Saffir-Simpson Hurricane Scale records hurricane intensity and the Enhanced Fujita Scale with tornadoes.

The Early Winter 2006 North American storm complex was a severe winter storm that occurred on November 26, 2006, and continued into December 1. It affected much of North America in some form, producing all kinds of severe weather including a major ice storm, blizzard conditions, high winds, extreme cold, a serial derecho and some tornadoes.

December 2009 North American blizzard

The December 2009 North American blizzard was a powerful nor'easter that formed over the Gulf of Mexico in December 2009, and became a major snowstorm that affected the East Coast of the United States and Canadian Atlantic provinces. The snowstorm brought record-breaking December snowfall totals to Washington, D.C., Baltimore, and Philadelphia.

2009 North American Christmas blizzard

The 2009 North American Christmas blizzard was a powerful winter storm and severe weather event that affected the Midwestern United States, Great Plains, Southeastern United States, the Eastern Seaboard, and parts of Ontario. The storm began to develop on December 22 before intensifying to produce extreme winds and precipitation by the morning of December 24. The storm's rapid development made it difficult for forecasters to predict. The blizzard was reported to have claimed at least 21 lives, and disrupted air travel during the Christmas travel season. In the Southeastern and Central United States, there were 27 reported tornadoes on December 23–24. The storm, a Category 5 "Extreme" one on the Regional Snowfall Index, was the first winter weather event to rank as such since the Blizzard of '96.

Global storm activity of 2009 profiles the major worldwide storms, including blizzards, ice storms, and other winter events, from January 1, 2009 to December 31, 2009. Wintery storms are events in which the dominant varieties of precipitation are forms that only occur at cold temperatures, such as snow or sleet, or a rainstorm where ground temperatures are cold enough to allow ice to form. It may be marked by strong wind, thunder and lightning, heavy precipitation, such as ice, or wind transporting some substance through the atmosphere. Summer storms including flooding, severe thunderstorms and extratropical cyclones are also included in this list to a certain extent.

Global storm activity of 2008

Global storm activity of 2008 profiles the major worldwide storms, including blizzards, ice storms, and other winter events, from January 1, 2008 to December 31, 2008. A winter storm is an event in which the dominant varieties of precipitation are forms that only occur at cold temperatures, such as snow or sleet, or a rainstorm where ground temperatures are cold enough to allow ice to form. It may be marked by strong wind, thunder and lightning, heavy precipitation, such as ice, or wind transporting some substance through the atmosphere. Major dust storms, Hurricanes, cyclones, tornados, gales, flooding and rainstorms are also caused by such phenomena to a lesser or greater existent.

Global storm activity of 2006 profiles the major worldwide storms, including blizzards, ice storms, and other winter events, from January 1, 2006 to December 31, 2006. Winter storms are events in which the dominant varieties of precipitation are forms that only occur at cold temperatures, such as snow or sleet, or a rainstorm where ground temperatures are cold enough to allow ice to form. It may be marked by strong wind, thunder and lightning, heavy precipitation, such as ice, or wind transporting some substance through the atmosphere. Other major non winter events such as large dust storms, Hurricanes, cyclones, tornados, gales, flooding and rainstorms are also caused by such phenomena to a lesser or greater existent.

December 1969 noreaster

The December 1969 nor'easter was a strong winter storm that mainly affected the Northeastern United States and southern Quebec between December 25 and December 28, 1969. The multi-faceted storm system included a tornado outbreak, record snow accumulations, a damaging ice storm, and flooding rains.

2013–14 North American winter

The 2013–14 North American winter refers to winter in North America as it occurred across the continent from late 2013 through early 2014. The winter of 2013–14 was one of the most significant for the United States, due in part to the breakdown of the polar vortex in November 2013, which allowed very cold air to travel down into the United States, leading to an extended period of very cold temperatures. The pattern continued mostly uninterrupted throughout the winter and numerous significant winter storms affected the Eastern United States, with the most notable one being a powerful winter storm that dumped ice and snow in the Southeast and Northeast in mid-February. Most of the cold weather abated by the end of March, though a few winter storms did affect the western portions of the U.S. towards the end of the winter.

2015–16 North American winter

The 2015–16 North American winter refers to winter in North America as it occurred across the continent from late 2015 through early 2016. Contrary to the past two winters, the United States experienced warmer conditions, mainly due to a strong El Niño. However, despite the warmth, significant weather systems still occurred, including a a snowstorm and flash flooding in Texas at the end of December and a large tornado outbreak at the end of February. The main event of the winter was when a crippling and historic blizzard struck the Northeast in late January, dumping up to 3 feet of snow in and around the metropolitan areas.

2011–12 North American winter

The 2011–12 North American winter refers to winter in North America as it occurred across the continent from late 2011 through early 2012. The 2011–12 season by and large saw above normal average temperatures across North America, with the contiguous United States encountering its fourth-warmest winter on record along with an unusually low number of significant winter precipitation events. The primary outlier was Alaska, which experienced its coldest January on record.

2010–11 North American winter

The 2010–11 North American winter season started in late 2010 and ended in mid-2011.

2016–17 North American winter

The 2016–17 North American winter refers to winter in North America as it occurred across the continent from late 2016 through early 2017. During the winter, a weak La Niña was expected to influence weather conditions across the continent. Several notable events occurred during the season, including a potent winter storm that affected the East Coast of the United States in early January, the second-largest winter tornado outbreak on record later that month, and an unusually warm February. In addition, towards the end of the season, a large cyclonic storm system that caused a large tornado outbreak, flooding, and a potent blizzard in the heart of the country. However, the most notable event of the winter was a powerful blizzard that impacted the Northeast and New England in mid-March, towards the end of the season.

2017–18 North American winter

The 2017–18 North American winter refers to winter in North America as it occurred across the continent from late 2017 through early 2018. Similar to the previous winter, a La Niña was expected to influence the winter weather across North America. Winter weather patterns were very active, erratic, and protracted, especially near the end of the season. Significant events included rare snowfall in the South, a strong cold wave that affected the United States during the early weeks of January, and a series of strong nor'easters that affected the Northeastern U.S during the month of March. In addition, flooding also took place during the month of February in the Central United States. Finally the winter came to a conclusion with a powerful storm system that caused a tornado outbreak and flooding in mid-April. The most intense event, however, was an extremely powerful cyclonic blizzard that impacted the northeastern United States in the first week of 2018.

2018–19 North American winter

The 2018–19 North American winter was winter in North America as it was occurring across the continent from late 2018 through early 2019. Notable events have included snow in the Southeast in December, a strong cold wave and several major winter storms in the Midwest, Northeast and much of Canada late January and early February, record snowstorms in the Southwest late February, two nor'easters that affected the east coast early March, deadly tornado outbreaks in the Southeast, collapsing buildings in Quebec, a historic mid-April blizzard in the Midwest, but the most notable event all season was a record-breaking bomb cyclone that affected much of North America mid March. Unlike previous winters, a developing El Niño was expected to influence weather patterns across North America.

The January 2019 North American winter storm was a long-lived winter storm, forming as a large area of low pressure off the Pacific Northwest shoreline January 16, making its way to the Northeast by January 21. Its effects included heavy rain/high elevation snow and gusty winds in California, Severe weather in the south, near-blizzard conditions in Upstate New York, an Ice Storm in New England and minor coastal flooding in the Mid-Atlantic.


  1. "Snow & Ice - FHWA Road Weather Management".
  4. Why, Who (2017-02-09). "Why do so many people die shovelling snow?". BBC News.
  5. "How do Potholes Form?".
  6. "Across Chicago area, melting snow contributes to dense fog".
  7. Smith A.B. and R. Katz, 2013: U.S. Billion-dollar Weather and Climate Disasters: Data sources, Trends, Accuracy and Biases. Natural Hazards, 67, 387–410, doi:10.1007/s11069-013-0566-5
  8. "Ice Storm December 25-26, 2000". National Weather Service Weather Forecast Office. National Oceanic and Atmospheric Administration. 31 July 2009. Retrieved 26 April 2016.
  9. Dolce, Chris; Erdman, Jon (12 February 2014). "The Nation's 10 Worst Ice Storms". Weather Underground. Retrieved 26 April 2016.
  10. "Presidential Disaster Declaration authorized for Kansas counties hit by January ice storm". Archived from the original on 25 April 2016. Retrieved 8 April 2016.