You weren't dreaming.

There was a brief tornado northwest of the Calgary airport Monday night, Environment Canada confirmed Tuesday.

"At approximately 8:20 p.m. on July 10, 2017 a brief tornado was observed 13 kilometres northwest of the Calgary International Airport," the agency reported.

"This was considered a non-mesocyclonic tornado that was generated by weak rotation under a rapidly developing thunderstorm. These types of tornados do not usually cause significant damage but can still be dangerous as they can topple trees, damage roofs, or toss debris a short distance."

The agency is looking for images or video of the tornado and any damage caused. Environment Canada can be reached at 1-800-239-0484, by email to ec.storm.ec@canada.ca or by tweeting with the hashtag #abstorm.