The definition of a tornado is a violently rotating column of air, in contact with the ground surface, either pendant from a cumuliform cloud or underneath a cumuliform cloud, and often visible as a funnel cloud.
Environment Canada has confirmed that 15 of these violently rotating columns of the air have touched down in the province so far this summer.
Though none have been reported in the Moose Jaw area so far this summer, the possibility is there for one to come through the city.
On average the province records approximately 17 tornadoes each year. Environment Canada says Saskatchewan is prone to more tornadoes each year than any other province in Canada – the question is why?
“It is a hotspot for tornadoes, we’re sort of the extension of the Tornado Alley that goes through the United States, we are on the northern extent,” says Environment Canada Meteorologist, Terri Lang.
Tornadoes can be formed from a number of storm types which include supercells, bow echoes and squall lines, pulse storms, and many more. Tornadoes need certain elements such as heat, moisture, wind, and trigger to come together to form a tornado.
“Heat is definitely one of the ingredients. When the heat starts to breakdown that’s when we get the storms and that’s when we tend to get the tornadoes.”
“The other thing we need is moisture, and this year we happen to have an abundance of moisture. One of the biggest contributing factors to moisture in the atmosphere is growing crops. We’re at peak growing time right now with the crops and they’re giving off tremendous amounts of moisture, it’s called evapotranspiration.”
Another element needed to form a tornado is winds in the upper atmospheres to be changing, which Saskatchewan has in spades.
“That allows the clouds to rotate, and when that happens the storms can get themselves more organized, and when the storms get more organized that’s when they’re more capable of producing tornadoes.”
The last thing needed for a tornado to form is a trigger – something to set things off.
“A cold front, an upper cold front, a trough, a dry line, something like that, that comes along to kick things off. Sometimes rain or lake breezes can do that, but those are the things that we need to set off the thunderstorms that are capable of producing tornadoes.”
If enough speed is created, tornadoes can create a lot of force that can do some serious damage. Data provided by Environment Canada says that tornadoes can generate wind speeds anywhere from 90-315 km/h, which can travel on average between 50 m and 100 plus kilometres.
With that generation of force comes severe damage to property, which is how tornadoes are measured by the Enhanced Fujita Scale (EF).
“They are rated based on the damage that they do. If we see a big tornado in a field and it doesn’t do any damage, we can’t give it a rating, because it doesn't do any damage. It had to hit something to be given a rating.”
In Canada, tornadoes are rated from EF0 with winds of 40-72 mph and light damage, all the way up to EF5 which has wind speeds ranging from 261-318 mph and creates catastrophic damage. Lang notes that the EF scale is used to rate a number of different types of winds.
Out of the 15 tornadoes that have touched down in the province this year, Lang says the most severe one so far was an EF1 tornado that tore through Foam Lake in late June. Environment Canada is investigating the severity of a tornado that touched down near Blaine Lake last weekend.
On June 29, Environment Canada confirmed three tornadoes on the same day. One each was confirmed near Manitou Beach, Margo, and Cymric.
Tornadoes come in various shapes and sizes, with some more severe than others. First, there are Supercells that tend to produce the most violent and long-tracked tornadoes due to sustained, intense updrafts.
Bow echoes are another form of a tornado that is likely prodigious tornado producers, and unlike supercells, they form out front of the storm.
Moving onto, Landspout tornadoes, they get their name from their formation and appearance are similar to waterspouts. Their damage is rarely greater than an EF1 and is very brief in its appearance.
Lastly, there is a Waterspout tornado, that is created over a body of water.
Though no tornadoes have touched down in the Moose Jaw area, a study by Dr. David Sills, who formally worked at the Cloud Physics and Severe Research Section for Environment Canada, showed that the area is the most susceptible to a tornado strike than anywhere else in Canada. The study showed that the Moose Jaw area has the potential to have three or more tornadoes per 10,000 kilometres squared a year.
The data also showed that due to the climate of southern Saskatchewan, EF2-EF5 tornadoes are more likely in the region.
In Canada’ there has only been one confirmed EF5 tornado, since adopting the EF Scale, which was back on June 22, 2007, that touched down in Elie, MB, just west of Winnipeg. It had winds in excess of 420 km/h, causing $39 million in damage, was on the ground for 40 min and travelled about six kilometres.
Though there’s never been an EF5 tornado in Saskatchewan, there have been five EF3s between 1980-2009.
In the event of a tornado, or even plough winds that can be common in the area, Environment Canada provides protocols for different situations, however, in all cases: get as close to the ground as possible, protect your head and watch for flying debris• do not chase tornadoes – they are unpredictable and can change course abruptly a tornado is deceptive. It may appear to be standing still but is, in fact, moving towards you. Tornado season on the prairies starts in April and can last until September.
In conclusion, Saskatchewan is a breeding ground for tornadoes due to its location being an extension of the USA’s Tornado Alley, its extreme heat, winds, and moisture levels due to crops.