Tornadoes

A tornado is a violently rotating column of extremely high winds that typically extend from a thunderstorm to the ground. They can appear after a heavy rain or hail in a sky that is green, yellow or black and can last from a few minutes to hours. With potential wind speeds ranging from 90km/hr to greater than 315km/hr on the Enhanced Fujita scale, the impact from a tornado can range from minor property damage to wide-scale devastation.

Tornadoes have been recorded in every province and territory in Canada however they typically occur in the southern areas of the prairies and Alberta as well as southern Ontario and across southern Quebec to New Brunswick. Tornado season is usually from May to September with July accounting for approximately a third of all activity. While they can occur at any time of day, data collected by the Northern Tornadoes Project suggests about half of all Canadian tornadoes accounted for occur between 4pm and 8 pm.

Stay Informed
Environment and Climate Change Canada issues Tornado Watches and Warnings for Ontario based on the following criteria:
  • Tornado Watch: When conditions are favourable for the development of severe thunderstorms with one or more tornadoes.
  • Tornado Warning: When a tornado has been reported; or when there is evidence based on radar, or from a reliable spotter that a tornado is imminent.

Environment and Climate Change Canada can issue a “broadcast immediate” alert through Alert Ready for all tornado warnings. Check if your cell phone is compatible with the Alert Ready system.

You may also receive local weather alert information by downloading the WeatherCAN app or you can check local weather and forecasts online at www.weather.gc.ca

Before
  • Know the potential signs of a tornado including:
    • severe thunderstorms, with frequent thunder and lightning
    • an extremely dark sky sometimes with green or yellow clouds
    • a rotating, funnel-shaped cloud,
    • an approaching cloud of debris,
    • a loud roar like a freight train or a whistling sound.
  • Consider purchasing a weather radio or using a weather alerting service available to the public (e.g. WeatherCAN app).
  • Remove dead or rotting trees and branches that could fall and cause injury or damage. Ensure items outside are stored away or tied down when high winds are in the forecast.
  • Consult the building department regarding wind-resistant construction for your home or business (e.g. bracing, anchorage, wind-rated garage doors).
  • Consider installing storm shutters to protect windows from airborne debris.
  • Ensure loose objects outdoors are put away or secured when not in use. Securely anchor outdoor appliances (e.g. air conditioner) and utility sheds.
  • Create an emergency plan and ensure you identify an interior location within a sturdy building that has no or very few windows in the basement or lowest level where you can shelter. Mobile, manufactured, trailer homes, and recreational vehicles (RVs) are not safe in high winds. If you are in one of these structures, you need to identify a sturdy building nearby that you can get to quickly.
  • Plan for power outages as they are often associated with severe weather including tornadoes. Charge devices (e.g. cell phones, laptops, tablets) prior to forecasted storms and consider installing an alternate power source (e.g. generator).
  • Build an emergency kit for your home and vehicle. Tornadoes can disrupt utilities and roadways (e.g. fallen trees, debris) for extended periods of time.
  • Review your homeowners or renters insurance to ensure you have adequate insurance for your property and personal belongings. Know what is covered, the level of coverage, and the deductible.
  • When the sky looks threatening, turn on your radio and monitor weather reports, or go to the WeatherCAN app or online at www.weather.gc.ca for more information.
  • Immediately before the storm hits and provided it is still safe to so,
    • disconnect electrical appliances such as computers, television sets, appliances and electronics that are charging if there is the potential for lightning
    • put your vehicle in the garage
    • bring pets and livestock to shelter unless there is an immediate risk of flooding
    • close outside windows and doors including garage doors
During
  • Seek suitable shelter immediately if a warning has been issued or if you believe a tornado could occur. Regardless of where you are when a tornado strikes, you should get as close to the ground as possible and protect your head, watch out for flying debris and avoid windows.
    • Within a home, go to the basement or lowest level and use the most interior room with the least amount of windows or other potential openings.
    • If in an office or apartment, take shelter in an inner hallway or room in the basement or lowest level. Do not use the elevator.
    • If in a large building with widespan roofing (e.g. gymnasium, auditorium, mall, arena, barn), look for more suitable shelter elsewhere as these buildings are more prone to collapse. If you are unable to do so, take cover under a sturdy object (e.g. table).
    • Mobile, manufactured, trailer homes, and recreational vehicles (RVs) are not safe in high winds. If you are in one of these structures, you need to identify a sturdy building nearby that you can get to quickly.
    • If you are driving, try to find suitable shelter. However, if the tornado is near you, get out of your vehicle and take cover in a low-lying area (e.g. ditch). Avoid taking shelter under bridges or overpasses.
  • Avoid unnecessary travel and do not chase tornadoes- they may be closer than they appear and can change directions quickly. Flying debris poses a significant risk to your safety.
  • Pay attention to local media and alerting systems for current emergency information and instructions.
After
  • Check with authorities and weather forecasts for information on whether it’s safe to go outside.
  • Watch for fallen power lines, trees and other debris.
  • If there has been heavy rainfall, avoid low-lying areas in case of flash flooding.
  • Check on vulnerable family members, friends and neighbours who may require assistance.
  • If your home or business appear to have significant structural damage, do not enter unless you are sure it is safe to do so. Rely on professionals to clear your home or business for re-entry if you are unsure. Take photos of the building and its contents for insurance claims.
  • Check with authorities on how to dispose of damaged items from your home.
  • Evaluate your emergency plan and restock your emergency kit.
Additional Resources