Tornadoes are violent windstorms characterized by a twisting, funnel-shaped cloud. Tornadoes usually move over the ground at anywhere from 20 to 90 kilometres per hour and often travel from the southwest to the northeast. It is not a good idea to chase tornadoes — they are unpredictable and can change course abruptly.
Tornadoes form suddenly, often preceded by warm, humid weather.
Warning signs include:
- Severe thunderstorms, with frequent thunder and lightning.
- An extremely dark sky, sometimes highlighted by green or yellow clouds.
- A rumbling sound, such as a freight train might make, or a whistling sound such as a jet aircraft might make. A funnel cloud at the rear base of a thundercloud, often behind a curtain of heavy rain or hail.
May to September are prime tornado months. Tornadoes usually hit in the afternoon and early evening but they have been known to strike at night too.
During a tornado
If you are at home:
- Go to the basement or take shelter in a small interior ground floor room such as a bathroom, closet or hallway.
- Failing that, protect yourself by taking shelter under a heavy table or desk.
- In all cases, stay away from windows, outside walls and doors.
If you are in an office or an apartment building:
- Take shelter in an inner hallway or room, ideally in the basement or on the ground floor.
- Do not use the elevator and stay away from windows.
Avoid buildings such as gymnasiums, churches and auditoriums with wide-span roofs. These roofs do not have supports in the middle and may collapse if a tornado hits them. If you are in one of these buildings, take cover under a sturdy structure.
Avoid cars and mobile homes. More than 50 per cent of all deaths from tornadoes happen in mobile homes. Take shelter elsewhere, preferably in a building with a strong foundation. If no shelter is available, lie down in a ditch away from the car or mobile home. However, beware of flooding from downpours and be prepared to move.
If you are driving and spot a tornado in the distance, try to get to a nearby shelter. If the tornado is close, get out of your car and take cover in a low-lying area.
In all cases, get as close to the ground as possible, protect your head and watch for flying debris. Small objects such as sticks and straws can become lethal weapons when thrown by a tornado's winds
*Keep in mind that if a tornado is heading straight for you, it may appear to be standing still.