An extreme cold warning is a

weather warning A weather warning or weather alert is issued by a meteorological agency to warn citizens of approaching dangerous weather. A weather watch, on the other hand, typically refers to an alert issued to indicate that conditions are favorable for the d ...

issued by

Environment and Climate Change Canada Environment and Climate Change Canada (ECCC; )Environment and Climate Change Canada is the applied title under the Federal Identity Program; the legal title is Department of the Environment (). is the department of the Government of Canada res ...

(ECCC) and by the United States'

National Weather Service The National Weather Service (NWS) is an Government agency, agency of the Federal government of the United States, United States federal government that is tasked with providing weather forecasts, warnings of hazardous weather, and other weathe ...

(NWS) to inform the public about active or imminent severe cold temperatures in their local region. In April 2014, ECCC replaced the " wind chill warning" with an "extreme cold warning." In the older system a

wind chill Wind chill (popularly wind chill factor) is the sensation of cold produced by the wind for a given ambient air temperature on exposed skin as the air motion accelerates the rate of heat transfer from the body to the surrounding atmosphere. Its va ...

warning for

Southern Ontario Southern Ontario is a Region, primary region of the Canadian Provinces and territories of Canada, province of Ontario. It is the most densely populated and southernmost region in Canada, with approximately 13.5 million people, approximately 36% o ...

and

Atlantic Canada Atlantic Canada, also called the Atlantic provinces (), is the list of regions of Canada, region of Eastern Canada comprising four provinces: New Brunswick, Newfoundland and Labrador, Nova Scotia, and Prince Edward Island. As of 2021, the landma ...

was issued when the wind chill dropped to -35. Thus a temperature of with no winds would not require a warning be issued. Under the new system the extreme cold warning is issued based on either the temperature or the wind chill being a certain value for at least two hours. The values range from temperatures to in parts of the

Arctic The Arctic (; . ) is the polar regions of Earth, polar region of Earth that surrounds the North Pole, lying within the Arctic Circle. The Arctic region, from the IERS Reference Meridian travelling east, consists of parts of northern Norway ( ...

.Extreme Cold Warning
/ref> On October 1, 2024, the NWS replaced the "wind chill warning" with the "extreme cold warning." The standards governing issuance are set by local NWS offices. The step below an extreme cold warning is an " extreme cold watch," which itself replaced the " wind chill watch" in October 2024.

Canada

An extreme cold warning is issued when the following temperatures are expected to last for at least two hours, which different regions have different criteria for: *

South South is one of the cardinal directions or compass points. The direction is the opposite of north and is perpendicular to both west and east. Etymology The word ''south'' comes from Old English ''sūþ'', from earlier Proto-Germanic ''*sunþa ...

Central Ontario Central Ontario is a secondary region of Southern Ontario in the Canadian province of Ontario that lies between Georgian Bay and the eastern end of Lake Ontario. The population of the region was 1,123,307 in 2016; however, this number does not in ...

and

Southwestern Ontario Southwestern Ontario (census population 2,796,367 in 2021) is a secondary region of Southern Ontario in the Provinces and territories of Canada, Canadian province of Ontario. It occupies most of the Ontario Peninsula, bounded by Lake Huron (includ ...

issued at *

Southeastern Ontario Eastern Ontario (census population 1,892,332 in 2021) () is a secondary region of Southern Ontario in the Canadian province of Ontario. It occupies a wedge-shaped area bounded by the Ottawa River and Quebec to the northeast and east, the St. Lawr ...

, the Southern Interior of British Columbia, the

British Columbia Coast The British Columbia Coast, popularly referred to as the BC Coast or simply the Coast, is a geographic region of the Provinces and territories of Canada, Canadian province of British Columbia. As the entire western continental coastline of Canada ...

and

(excluding Labrador) issued at *

Quebec Quebec is Canada's List of Canadian provinces and territories by area, largest province by area. Located in Central Canada, the province shares borders with the provinces of Ontario to the west, Newfoundland and Labrador to the northeast, ...

(excluding northern Quebec) issued at *

Northern Ontario Northern Ontario is a primary geographic and quasi-administrative region of the Provinces and territories of Canada, Canadian province of Ontario, the other primary region being Southern Ontario. Most of the core geographic region is located on p ...

(excluding the far north),

Central Interior of British Columbia Central is an adjective usually referring to being in the center of some place or (mathematical) object. Central may also refer to: Directions and generalised locations * Central Africa, a region in the centre of Africa continent, also known as ...

and the

Prairies Prairies are ecosystems considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and a composition of grasses, herbs, and shrubs, rather than trees, as the ...

(

Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...

southern Manitoba Southern Manitoba is the southernmost area of the Canadian province of Manitoba. Southern Manitoba encompasses the Winnipeg Metropolitan Region, Westman Region, Central Plains Region, Eastman Region, and Pembina Valley Region, as well as the Man ...

, southern

Saskatchewan Saskatchewan is a Provinces and territories of Canada, province in Western Canada. It is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and to the south by the ...

) issued at *Far northern Ontario,

northern Manitoba Northern Manitoba (also known as NorMan or Nor-Man) is a geographic and cultural region of the Canadian province of Manitoba. Manitoba originally encompassed only a small square around the Red River Colony, but it was extended north to the 60th ...

(excluding northeastern Manitoba), northern Saskatchewan,

Northern Interior of British Columbia Northern may refer to the following: Geography * North, a point in direction * Northern Europe, the northern part or region of Europe * Northern Highland, a region of Wisconsin, United States * Northern Province, Sri Lanka * Northern Range, a ra ...

and

Labrador Labrador () is a geographic and cultural region within the Canadian province of Newfoundland and Labrador. It is the primarily continental portion of the province and constitutes 71% of the province's area but is home to only 6% of its populatio ...

issued at *

Northern Quebec Northern Quebec () is a geographic term denoting the northerly, more remote and less populated parts of the Canada, Canadian province of Quebec.Alexandre Robaey"Charity group works with Indigenous communities to feed Northern Quebec's 'wandering dog ...

(excluding Nunavik) issued at *

Yukon Yukon () is a Provinces and territories of Canada, territory of Canada, bordering British Columbia to the south, the Northwest Territories to the east, the Beaufort Sea to the north, and the U.S. state of Alaska to the west. It is Canada’s we ...

Northwest Territories The Northwest Territories is a federal Provinces and territories of Canada, territory of Canada. At a land area of approximately and a 2021 census population of 41,070, it is the second-largest and the most populous of Provinces and territorie ...

(excluding Paulatuk, Sachs Harbour, Ulukhaktok),

Baffin Island Baffin Island (formerly Baffin Land), in the Canadian territory of Nunavut, is the largest island in Canada, the second-largest island in the Americas (behind Greenland), and the fifth-largest island in the world. Its area is (slightly smal ...

, and northeastern

Manitoba Manitoba is a Provinces and territories of Canada, province of Canada at the Centre of Canada, longitudinal centre of the country. It is Canada's Population of Canada by province and territory, fifth-most populous province, with a population ...

issued at *

Nunavik Nunavik (; ; ) is an area in Canada which comprises the northern third of the province of Quebec, part of the Nord-du-Québec region and nearly coterminous with Kativik. Covering a land area of north of the 55th parallel, it is the homelan ...

issued at *Northwest Territories ( Paulatuk,

Sachs Harbour Sachs Harbour ( ; ) is a Hamlet (place)#Canada, hamlet located in the Inuvik Region of the Northwest Territories, Canada. Situated on the southwestern coast of Banks Island in the Inuvialuit Settlement Region, the population according to the 202 ...

, Ulukhaktok only) and

Nunavut Nunavut is the largest and northernmost Provinces and territories of Canada#Territories, territory of Canada. It was separated officially from the Northwest Territories on April 1, 1999, via the ''Nunavut Act'' and the Nunavut Land Claims Agr ...

(excluding Baffin Island) issued at

United States

In the United States an extreme cold warning was an experimental weather warning issued by the

North Dakota North Dakota ( ) is a U.S. state in the Upper Midwest, named after the indigenous Dakota people, Dakota and Sioux peoples. It is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minneso ...

South Dakota South Dakota (; Sioux language, Sioux: , ) is a U.S. state, state in the West North Central states, North Central region of the United States. It is also part of the Great Plains. South Dakota is named after the Dakota people, Dakota Sioux ...

, and

Minnesota Minnesota ( ) is a U.S. state, state in the Upper Midwestern region of the United States. It is bordered by the Canadian provinces of Manitoba and Ontario to the north and east and by the U.S. states of Wisconsin to the east, Iowa to the so ...

. The warning was issued if the temperature fell to or colder with a wind of less than . It was an experimental advisory for when the air temperature was dangerously cold, but the wind was too little to warrant a Wind Chill Watch or Warning. The Extreme Cold Warning was used from January 10, 2011 to April 15, 2011. It was discontinued beginning with the 2011-12 winter storm season. Only five Extreme Cold Warnings were issued in that period: one for Burleigh County, three for areas outside of the

Bismarck–Mandan Bismarck–Mandan, colloquially referred to as BisMan, is the metropolitan area composed of Burleigh, Morton, and Oliver counties in the state of North Dakota. Its core cities, Bismarck and Mandan, are located on opposite sides of the upper ...

metropolitan area, and one for

West Glacier, Montana West Glacier is an unincorporated community and census-designated place (CDP) in eastern Flathead County, Montana, United States. As of the 2020 census it had a population of 221. The town is at the west entrance to Glacier National Park and i ...

In a partner webinar on October 30, 2018, the National Weather Service announced that based on survey feedback, the Extreme Cold Warning and the Wind Chill Warning will be consolidated into the Extreme Cold Warning, meaning that this product would once again be issued on a regular basis. This change was hinted to take effect sometime in 2021, accounting for NWS software upgrades. This was confirmed at the AMS 2024 meeting in January 2024. In October 2024, the NWS officially implemented these changes to its wind chill and hard freeze warnings, watches, and advisories (WWAs) as part of its "Hazard Simplification initiative." The goal of these WWA name changes, per the NWS, is "simplifying a suite of cold weather forecast products to improve messaging of winter hazards and provide better decision support." The changes include: Extreme Cold Consolidation and Renaming *Wind Chill Watch was renamed to Extreme Cold Watch *Wind Chill Warning was renamed to Extreme Cold Warning *Wind Chill Advisory was renamed to Cold Weather Advisory Freeze Consolidation *Hard Freeze Watch was renamed to Freeze Watch *Hard Freeze Warning was consolidated to Freeze Warning
^{''Local NWS offices will still determine the standards governing the issuance of such WWAs.''}

Example of an Extreme Cold Warning (United States)

URGENT - WEATHER MESSAGE
National Weather Service Twin Cities/Chanhassen MN
451 PM CST Mon Jan 20 2025

MNZ054-056>060-062-064>070-073>077-082>085-091>093-210700-
/O.UPG.KMPX.CW.Y.0002.000000T0000Z-250121T1800Z/
/O.EXA.KMPX.EC.W.0001.000000T0000Z-250121T1800Z/
Lac Qui Parle-Chippewa-Kandiyohi-Meeker-Wright-Hennepin-Ramsey-
Yellow Medicine-Renville-McLeod-Sibley-Carver-Scott-Dakota-
Redwood-Brown-Nicollet-Le Sueur-Rice-Watonwan-Blue Earth-Waseca-
Steele-Martin-Faribault-Freeborn-
Including the cities of Chanhassen, Waseca, Mankato, Fairmont,
Victoria, Albert Lea, Olivia, St James, Hastings, Owatonna,
Gaylord, Minneapolis, Granite Falls, Willmar, Monticello,
Madison, Litchfield, Hutchinson, Montevideo, Faribault, Chaska,
St Peter, Le Sueur, New Ulm, Redwood Falls, St Paul, Shakopee,
and Blue Earth
451 PM CST Mon Jan 20 2025

...EXTREME COLD WARNING IN EFFECT UNTIL NOON CST TUESDAY...

* WHAT...Dangerously cold wind chills as low as 37 below.

* WHERE...Portions of central, east central, south central,
  southwest, and west central Minnesota.

* WHEN...Until noon CST Tuesday.

* IMPACTS...The dangerously cold wind chills could cause frostbite
  on exposed skin in as little as 10 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Persons are urged to stay indoors until conditions improve. If you
must go outside, dress in layers. Several layers of clothes will
keep you warmer than a single heavy coat. Cover exposed skin to
reduce your risk of frostbite or hypothermia. Gloves, a scarf, and a
hat will keep you from losing your body heat.

Keep pets indoors as much as possible.

Make frequent checks on older family, friends, and neighbors. Ensure
portable heaters are used correctly. Do not use generators or grills
inside.

&&

$$

Example of an Extreme Cold Warning (Canada)

3:15 PM CST Monday 3 February 2025
Extreme Cold Warning in effect for:

City of Regina

A multi-day episode of very cold wind chills is expected.

Dangerous wind chill values of minus 40 or colder continue.

Overnight low temperatures approaching minus 30 coupled with winds of 10 to 15 km/h will produce extremely cold wind chill values of minus 40 to minus 45 over the coming days.

Snow moving in from the United States will likely push regions between the international border and the Transcanada Highway above extreme cold thresholds by Tuesday morning. However, areas to the north, in the vicinity of the Yellowhead, will continue with the bitterly cold temperatures into Wednesday morning.

Temperatures are expected to moderate for most by Thursday.

Extreme cold puts everyone at risk.

Risks are greater for young children, older adults, people with chronic illnesses, people working or exercising outdoors, and those without proper shelter.

Watch for cold related symptoms: shortness of breath, chest pain, muscle pain and weakness, numbness and colour change in fingers and toes.

Cover up. Frostbite can develop within minutes on exposed skin, especially with wind chill.

If it’s too cold for you to stay outside, it’s too cold for your pet to stay outside.

Outdoor workers should take regularly scheduled breaks to warm up.

Extreme cold warnings are issued when very cold temperatures or wind chill creates an elevated risk to health such as frost bite and hypothermia.

Please continue to monitor alerts and forecasts issued by Environment Canada. To report severe weather, send an email to [email protected] or tweet reports using #SKStorm.

References

{{SevWea nav, state=collapsed Weather warnings and advisories Meteorological Service of Canada Climate of Canada

Canada

United States

Example of an Extreme Cold Warning (United States)

Example of an Extreme Cold Warning (Canada)

See also

References