YouTube video courtesy of Michelle Wiebe, who believes this could be the tornado near Taber

Southern Alberta was shaken by tornadoes late Tuesday, downing trees and cutting power in at least one town, with the same weather system bringing thunderstorms to Calgary.

Environment Canada confirmed one tornado near Taber and was investigating reports of three others late Tuesday.

The first twister was seen eight kilometres south of Taber at approximately 8:30 p.m. MT.

There were also reports of tornadoes near Brooks, Vulcan and Bow Island from 10:30 p.m. to 11 p.m. MT.

Taber Mayor Ray Bryant told CBC News that the tornado touched down south of the community, which is three hours southeast of Calgary, leaving much of the town without power.

Taber police said they were being overloaded with calls, but they asked people not to call 911 unless it was life-threatening or a crime was in progress.

Environment Canada is advising people in the area to be on the lookout and take the necessary safety precautions.

The Alberta Emergency Alert system categorized their critical alerts for the areas of Taber and Lethbridge as "imminent life-threatening danger."

'My truck was rocking'

Leah Moore, a Taber resident, said she was on her way home from work, between Taber and Barnwell, when she had to pull over.

Moore said that the sky was black for about 15 minutes.

"My truck was rocking," Moore told CBC News.

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"I thought for a bit it might tip over."

The storm quickly tracked north, said CBC Calgary meteorologist Danielle Savoni.

"Warnings are changing every minute, because there are a number of severe cells in Alberta right now, and at least five more tracking towards the province from Montana," said Savoni.

"All of southern Alberta should take this seriously and stay indoors."

The warning also extends into a portion of Saskatchewan, according to Environment Canada.