Government of Canada
Symbol of the Government of Canada
Welcome to the
Canadian Atmospheric Hazards Network
A portal to five regional Hazards sites across Canada:
Pacific and Yukon Prairie and Northern Ontario Quebec Atlantic

Hazards Regions

Every year, Canadians are impacted by severe weather events such as snowstorms, severe thunderstorms, wind storms, heat waves and tornadoes. Damage to or loss of homes, properties and businesses as well as disruption and damage to electrical, communication and transportation systems can result from these storms. Heat waves and cold spells can be hazardous to human health.

The numbers and costs of extreme weather events, particularly the more infrequent weather-related disasters, are on the rise globally and in Canada. The social and economic toll from the weather disasters can be staggering. During the 1st week of January, 1998, a crippling Ice Storm impacted about 25% of Canada's population in Ontario, Quebec, New Brunswick and Nova Scotia as well as 7 states in the Northeastern U.S. In 2010, it remains Canada's costliest weather disaster with total insured damages estimated at over $5 billion and 28 human fatalities in Canada. Ontario's most expensive weather disaster occurred on August 19, 2005 when extreme rainfall resulted in destructive flash flooding in Toronto and 2 tornadoes struck northwest of the City. Damages exceeded $500 million in insured losses, also marking this as the second most expensive insurance storm event in Canada's history.

Major weather disasters have occurred from coast to coast in Canada and are etched in Canadians' memories due to their devastating impacts. The Pine Lake tornado that struck central Alberta in July 2000 tragically took the lives of 12 people when it struck a campground and trailer park. On August 20, 2009, 18 tornadoes crossed southern Ontario, a record number of tornadoes observed on one day in Canada. The tornadoes left one boy dead and a trail of destruction that included extensive damage to 600 homes in the City of Vaughn, just north of Toronto, with 38 of these homes declared unsafe and demolished.

Torrential rains in the Saguenay region in July 1996 resulted in the worst flooding in Quebec's history with thousands of evacuations and 2 deaths. The following year flooding on the Red River resulted in the largest mass evacuation in Canadian history, over 100,000 people, and damage losses in excess of $500 million.

The devastating windstorms that struck Stanley Park, Vancouver in December 2006 levelled over 1000 trees in the Park and did extensive damage to the seawall. In September 2003, Hurricane Juan made landfall near Halifax, Nova Scotia as one of the most powerful and damaging hurricanes to ever affect the region.


Environment Canada, working with Emergency Management Ontario, recently conducted a survey of over 400 Ontario municipal Emergency Management Coordinators; 86% of Ontario municipalities ranked weather and weather-related hazards (e.g. power outages) as priority risks to their communities and the safety of their residents. This underscores the need for Canadians to have readily-available comprehensive atmospheric hazards information. The Canadian Atmospheric Hazards Network was developed by Environment Canada to help individuals, municipalities and provincial/territorial governments identify and assess their risks to atmospheric hazards for planning and decision-making activities, including the development of community and provincial emergency management plans. The site provides information on the types of atmospheric hazards common to each of the 5 Canadian regions and the climatology of these hazardous events. The hazards information is available through a series of maps and graphics with supplementary hazards datasets and documentation.