Guide to understanding Canadian tornadoes, and the history

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Monday, May 7, 2018, 4:30 PM - We are inundated with videos and images of tornadoes in the United States. We’re watching them live on Periscope and viewing them through 360 cameras showing us their destruction and beauty like never before. More and more, now, we are seeing these same videos and images from all around the world. 

The world has never been smaller from an information standpoint and it’s making it that much easier to see that large tornadoes occur elsewhere around the globe, including our beautiful homeland of Canada.

The Database

We know Canada gets tornadoes and a couple of years ago we compiled some key information of where tornadoes occur in Canada. We’d like to take the opportunity to update that with new information about tornado-prone areas in Canada. In the early spring of 2016, the Government of Canada published its Tornado Database for events 1980-2009. This database was compiled and studied by a group of scientists, researchers and meteorologists led by Dr. David Sills at Environment Canada (full accreditation at the end of the article).

Below is an image of tornadoes from 1980-2009 in Canada with the colours representing the various tornado ratings. Followed by the high-end tornadoes (F3 and higher) from 1980-2009.

How are tornadoes rated? Tornadoes are rated based on a damage scale, called the “Fujita Scale” (F-scale) first compiled by Dr. Tetsuya Fujita in the 1970’s based on extensive research of tornado damage. The scale was later changed to the “Enhanced Fujita Scale” (EF-scale) in 2007 where new research was able to better discern wind speeds based on damage. The scale ranges from 0 (least destructive) to 5 (most destructive) and the associated wind speeds are listed below.

As you can see from the map of confirmed tornadoes across Canada (1980-2009), it’s clear that tornadoes can happen all over our country from Newfoundland’s rocky coasts to the Rocky Mountains of British Columbia. What is also clear is that tornadoes occur with more frequency in certain provinces compared to others. Saskatchewan is the province with the highest frequency, on average, of tornadoes per year. Based on confirmed tornadoes, Canada’s average number of tornadoes per year was found to be about 62.

That doesn’t seem like a lot when comparing to the U.S.’s 1200+ average tornado count per year but the research didn’t stop there. As mentioned in a previous article, the research team used the database to help model tornado incidence. Items such as lightning flash density climatology and a population density mask were used to correct for population bias. Canada is a large country and certain regions are very sparse for population so if someone isn’t there to see the tornado, it becomes difficult to know if one occurred. After applying this modelling technique, the research team was able to conclude that it is possible that 230 tornadoes occur across Canada each year! 

Big Tornado Events 

It has been some time since a major tornado event has occurred in Canada. August 20, 2009 had 19 tornadoes touch down across Ontario. On June 22, 2007, Canada first and only (to date) F5 tornado touched down in Elie, Manitoba followed by the Pipestone tornado on June 23. July 31, 1987, 27 people lost their lives, 300 injured during the Edmonton tornado. Not in the database (because the data ends for now at 2009), were the devastating F3 Goderich tornado of 2011 and the powerful EF2 Tilston, Manitoba tornado of 2015.

Just over 20 tornadoes were confirmed in Canada in 2015 compared to the 62 average. Some years are slower than others but some are also much busier than others like the 2012 tornado season which saw over 40 tornadoes confirmed that year, many of them in Saskatchewan. It does not need to be a busy tornado year for a devastating tornado to occur. In fact, it is very difficult to know ahead of time whether or not it will be a busy tornado season. Tornadoes are meteorological phenomenon that are very difficult to predict let alone weeks or months ahead of time. Tornadoes come down to days, hours, minutes as they happen on such a small scale in comparison to our atmosphere.

Goderich tornado

The growing concern is for a significant tornado to impact a major city in Canada. It’s no secret that many of Canada’s urban areas are growing, sprawling into new geographical locations to make up for our growing population. A good example is the continuing expansion of the southern Ontario population. Many live outside Toronto in what’s known as the Greater Toronto Area or north of that area. Areas that were once farm land or open fields are now being developed for homes and subdivisions. These homes are being built through southern Ontario’s most tornado-prone areas. If we overlay the track of the 1985 Barrie tornado to the map now, it’s scary to see that the tornado would have caused a lot more damage and injuries had it happened today.

We cannot predict now when the next big tornado will happen or what town it will hit. What we can say is that we need to educate ourselves and plan accordingly. Ask yourself if you have a severe weather plan. Do you and your family know what to do in case of a tornado? Where should you go in your house? What if you’re driving? Summer severe weather can give very little notice so it’s important we educate ourselves and prepare. Canada does get tornadoes and every province and territory has the opportunity to see a tornado; we can see it in the research. Stay up to date on your forecasts throughout the summer months and ensure you have a way to stay informed. Several ways you can do this including Canada’s new Alert Ready system. If you’re away from a radio or television though, here are some tools to keep you informed and safe:

• Push alerts from The Weather Network app
• Follow reliable sources on social media 
• Weather radio

Canadian Tornado Facts 

Strongest tornado: F5, Elie Manitoba on June 22, 2007

Most tornadoes in a single day: 19 tornadoes in southern Ontario on August 20, 2009

Longest tornado path: 115 km path of F4 tornado from Grand Valley to Tottenham, Ontario on May 31, 1985

Widest tornado path: 1,800 m (1.8 km!) wide Pipestone, Manitoba F3 tornado on June 23, 2007 

Most fatalities and injuries: 28 fatalities during F4 tornado in Regina, Saskatchewan on June 30, 1912

Resources 

Sills, D., V. Cheng, P. McCarthy, B. Rousseau, J. Waller, L. Elliott, J. Klaassen and H. Auld, 2012: Using tornado, lightning and population data to identify tornado prone areas in Canada. Extended Abstracts, 26th AMS Conference on Severe Local Storms, Nashville, TN, American Meteorological Society, Paper P59. 

Cheng, V. Y. S., G. B. Arhonditsis, D. M. L. Sills, H. Auld, M. W. Shephard, W. A. Gough, and J. Klaassen, 2013: Probability of tornado occurrence across Canada. Journal of Climate, 26, 9415-9428. 

Cheng, V. Y. S., G. B. Arhonditsis, D. M. L. Sills, W. A. Gough and H. Auld, 2015: A Bayesian modeling framework for tornado occurrences in North America. Nature Communications, 6, 6599.