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1970 Sudbury tornado

A tornado is the stuff of nightmares. Amid heavy rain and hail, huge thunderclouds roll in and the skies turn greenish-black. And then a rope-like funnel cloud punches down, smashing everything in its path. Tornadoes can be the most violent storms on earth, and Canada averages 80 of them each year. From scientists and storm chasers obsessed with their destructive power to the victims left in a twister's wake, we look at Canada's deadliest tornadoes of the past century.

Tornadoes rarely hit northern Ontario, so the city of Sudbury is ill-prepared for the freak storm that rips through town on Aug. 20, 1970. Scores of smashed homes are only the beginning of Sudbury's problems. As we hear from eyewitnesses in this report, the Inco copper smelter is trashed, pumping stations are out and raw sewage is polluting the drinking water. Yet the city's mayor is proud of the relief efforts already underway and the resilience of the townsfolk, who he says are "a very hardy species." 
. Tornadoes occur when warm, humid air encounters cool, dry air. The cool air traps the warm air, preventing it from rising. The trapped air is further warmed by the earth, and begins to rotate, eventually punching through the cold air above. That cold air falls quickly, creating a "downburst" that forces even more warm air upward. The system spins and creates a funnel cloud.

. In general, tornadoes become less common the further north you go. As temperatures decrease further north, hot and cold air masses mix less frequently. Tornadoes seldom occur as far north as Sudbury.
. A TV clip about this tornado can be found in our "On This Day..." section.

. Canada has a few "tornado alleys" where twisters occur most frequently. According to Environment Canada these include southern Ontario, Alberta, southeastern Quebec, and a band that stretches from southern Saskatchewan to Thunder Bay. The British Columbia interior and western New Brunswick are also considered tornado zones.

. According to Environment Canada's website, here's what to do if you are caught in a tornado:
- If you are indoors, head to the basement. If there isn't one, find a closet or small room near the centre of the building, away from doors and windows. Some sources recommend getting into a bathtub and covering yourself with a mattress, or hiding under a table or sturdy piece of furniture. Leave windows shut and stay away from them.

- If you are in a car, get out and go to a place where the car can't roll on top of you. A car may offer some protection against a weak tornado, and allow you to drive to a better shelter. But don't count on being able to outrun a tornado - they travel as fast as a car and don't have to follow roads. If you see a tornado in the distance and can tell which way it is moving, attempt to drive perpendicularly away from it.

- If you are outdoors, find a ditch or low-lying area and lie down, shielding your head with your arms.
- If you are in a mobile home, get out and find better shelter in a permanent building or ditch. More than half of all tornado deaths occur in mobile homes. There's a myth that tornadoes are attracted to mobile homes and trailer parks, but the reality is that the dwellings are simply more vulnerable to damage due to their flimsy construction.

. Environment Canada advises that no matter where you are, you should always watch the weather and listen to a radio station that broadcasts weather bulletins. Have a plan in place, know the location of the nearest best shelter, and keep an emergency kit with first aid supplies, food, clothing, blankets, batteries and tools.
Medium: Radio
Program: Sunday Magazine
Broadcast Date: Aug. 23, 1970
Guest(s): Herb Akers, Robert Andras, Blanchard Bell, Joe Fabbro, Darcy McKeough, Jim Samble, Dennis Semechenko, Thomas Thompson
Host: John O'Leary, Bruce Rogers
Duration: 12:55

Last updated: August 21, 2012

Page consulted on December 6, 2013

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