Storm chasers flock to Alberta as weather worsens

Storms chasers are flocking to Alberta and Saskatchewan, where they say weather conditions have created a perfect storm for tornadoes and thunderstorms.

• Tornado warnings for Claresholm, High River, Okotoks as weather warnings expand

A severe thunderstorm bore down on Okotoks, High River and Claresholm around 5 p.m. Saturday. Meteorologists with Environment Canada used radar to detect a possible tornado in that storm, south of Longview.

"This is a dangerous and potentially life-threatening situation," they warned in a release.

"If you hear a roaring sound or see a funnel cloud, swirling debris near the ground, flying debris, or any threatening weather approaching, take shelter immediately."

The organization also issued severe thunderstorm warnings for another eleven communities in southern Alberta.

In late June, teams of storm chasers descended on Alberta and Saskatchewan, brandishing cameras for the tornado season ahead.

"The last five years have been an absolute tornado recession," said Greg Johnson about weather patterns in both provinces. "It's just nice for us to not have to drive 3,000 kilometres to see something."

The Alberta-Saskatchewan border rebounded as prime territory for tornadoes last month, said the photographer for the Tornado Hunters storm-chasing team. In fact, Johnson said he's unused to seeing tornadoes this early in the year.

"Tornadoes are a different animal," he said. "I always liken it to baking a cake. You have to have four ingredients and if you don't have one of those ingredients you're just not going to have any chance of a tornado."

Not quite as photogenic as the Alberta storms today but I will take this shot from Chamberlain, SK this evening <a href="https://t.co/C5OzcSIVRu">pic.twitter.com/C5OzcSIVRu</a>

&mdash;@TornadoGreg

Johnson uses the acronym SLIM to track storms and predict tornadoes: shear, lift, instability and moisture.

He explains 'shear' as "different heights in the atmosphere having different winds travelling at different speeds," which creates a swirling storm. Lift is required to mix warm moist air with cold dry air, he said, and weather instability results from a build-up of heat.

The final ingredient Johnson looks for is moisture, which he said is rare in Alberta and Saskatchewan.

"If you're missing one ingredient, you got no cake. You can still have a mess going on in the oven, but you're not going to have a cake."

Others left behind the promise of 'Tornado Alley' in the United States to chase storms across Alberta instead.

Oklahoma-based photographer Ben Holcomb watched a supercell cloud and tornado unfurl west of Didsbury, about 80 km north of Calgary, on Friday.

"It was extremely photogenic and was a nice little welcome to Canada for me," Holcomb said.

Ronnie Rabena watched the same storm from a different field.

"We've been pretty busy," said the founder of Alberta's Twisted Chasers team. "It's good for us storm chasers. 

"I mean obviously we would never want to see a tornado go through a city or damage any farms, we want to see it out in the open field."

Rabena warns amateur chasers not to take storms lightly and recommends they find someone experienced to work with. 

"You have to be able to read a storm," he said.

If you captured photographs of Alberta storms worth sharing, send them to webedmonton@cbc.ca.

@ZoeHTodd