Several tornado sightings were reported as wild weather ripped through Alberta and Saskatchewan Tuesday.

There was at least one confirmed report of a tornado touching down west of Didsbury, Alta., Calgary's 660 News radio station reported. Witnesses described swirling clouds and a pitch-black sky, with heavy wind, rain, lightning and hail.

Twitter users reported other twisters. Self-described tornado hunter Greg Johnston (@canadogreg) spent the day chasing storms and posted live streaming video of a touchdown near Outlook, Sask.

Parts of south and central Saskatchewan, including Regina and Saskatoon, had been under weather warnings all day as meteorologists feared some storms they observed had the potential to develop into tornadoes.

Environment Canada warnings and watches remained in effect Wednesday morning for many parts of Alberta, as an "intense weather system" was expected to move through the central part of the province and into western Saskatchewan, bringing winds up to 100 km/h and severe thunderstorms.

High winds and rain were also expected in the northern and southern parts of Alberta.