There was no immediate word whether the twister touched down, but Environment Canada said at 11:30 a.m. CST, storm spotters reported a tornado between Yorkton and Bredenbury near Saltcoats.
Micheal Lam, a project engineer who was on a job near Bredenbury, told CBC News he saw the tornado about 15 kilometres away, moving southeast.
"It was my first tornado — ever — that I've ever seen with my own two eyes," he said. "It was kind of startling ... kind of a surreal experience."
The funnel cloud took five to 10 minutes to form, then touched down, possibly in a field, Lam said.
"Just a very narrow funnel cloud to start with, and it eventually worked its way to the ground," he said. "Then it was just a thin, ropey-type tornado."
After about 10 minutes, the tornado dissipated, he said.
Environment Canada is telling people that if threatening weather approaches, they should seek shelter in a sturdy permanent building or underground.
If there are tornadoes, vehicles, mobile homes, cottages, boats, tents and trailers are considered unsafe, the weather agency says.
As the day progressed, Environment Canada said the severe weather was moving eastward through Saskatchewan.
Severe thunderstorm warnings were issued for Kamsack, Moosomin and Yorkton. Those areas were also under a tornado watch.
According to emergency planning officials, Saskatchewan records — on average — about 15 confirmed tornadoes in a typical season, which runs from May to August. In 2012, there were 33. Most of those were noted from mid-June to the end of July.
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