Recent severe weather incidents have had area residents joining people across the country in seeking weather updates through online, broadcast and print media.
Severe weather such as last December’s ice storm on the early January blizzard and steep temperature plunge can create dangerous, even life-threatening conditions. On it’s website, Environment Canada notes that in an average year, more Canadians die from exposure to winter cold than from lightning, wind storms and tornadoes combined.
When severe winter weather threatens, Environment Canada issues special alerts that notify Canadians in affected areas so they can take steps to protect themselves and their property from harm. These weather alert bulletins are issued through the media, as well as through the Weatheradio service, and the Government of Canada’s weather.gc.ca website.
Canada experiences a wide variety of dangerous weather conditions, including extreme cold, blinding blizzards and treacherous ice storms. And it’s not just the weather itself that can have serious consequences, the agency notes, but also the rapid transitions between weather types or the long durations of any one particular type that occur from time to time. It’s one thing to be prepared for the cold, snow and ice, but Canadians also have to be ready for those times when the weather changes in the blink of an eye or when nasty conditions seem to go on forever?
This is why it’s important to be aware of the various weather alerts available from Environment Canada, which are issued to help citizens make informed decisions. The type of alert used depends on the severity and timing of the event:
– “special weather statements” are the least urgent type of alert. These are issued when conditions are unusual and could cause concern. They provide a heads up of what weather may be coming;
– “watches” alert citizens about weather conditions where there is potential for a significant storm or severe weather to occur. As certainty increases about the path and strength of a storm system, a Watch could be upgraded to a Warning; and
– “warnings” are urgent messages that severe weather is either occurring or will occur. These alerts are updated regularly so residents can stay informed and take appropriate action.
Of the above types of alerts, different weather patterns can bring different types of threats/hazards.
These can generally be defined as precipitation events (snow, freezing rain, etc.), extreme cold and wind chill, and reduced visibility. Any of the three threats can arrive alone or in combination of two or more.
Environment Canada issues over 20 different types of alerts for the various weather hazards that are possible across the country.
But to simplify, winter alerts can be categorized into three basic categories (each of which can occur in combination with another). Precipitation alerts include:
– snowfall, significant snowfall;
– snow squall, when cold air moves across larger open bodies of water (such as the Great Lakes) creating nearly stationary bands of cloud and snow;
– freezing rain/drizzle, when rain or drizzle falls onto sub-zero surfaces and freezes on contact forming a layer of ice;
– rainfall, significant rainfall; and
– winter storm, issued when multiple types of severe winter weather are expected to occur together.
Cold alerts include:
– wind chill, wind or cold on their own may not be hazardous, but the combination of the two may warrant issuing this type of alert; and
– flash freeze, issued when a rapid drop in temperature causes water from rain or melted snow on streets, sidewalks etc. to quickly freeze.
Poor visibility alerts include:
– blizzard, issued when winds are expected to create blowing snow giving widespread reduced visibility of 400 metres or less; and
– blowing snow, issued when winds are expected to create blowing snow giving poor visibility of 800 metres or less.
There is also a rarely-issued generic alert simply called a “weather” warning. It may be issued for extreme weather events for which there is no suitable warning type, because they rarely occur (e.g. a major fog event).
The federal government is currently working on a new system under which Canadians will no longer see separate wind chill warnings in Environment Canada forecasts or on its website. Wind chill and cold temperatures will be included together in the “extreme cold warnings.”
