By CBC News Ottawa, July 24, 2018
Environment Canada has confirmed that a supercell passed over the eastern Ontario village of Bourget on Monday night.
Meteorologist Peter Kimbell examined an image of a large cloud hovering above church spires in Bourget — about 50 kilometres east of Ottawa — and then analyzed Doppler radar to determine the storm system's velocity and to categorize it.
"It's a pretty good, classic photograph of a wall cloud… the rotating part of a supercell thunderstorm," he said. "It's a fairly classic image of one. We don't see these that often, certainly not in eastern Ontario."
http://www.cbc.ca/news/canada/ottawa/supercell-bourget-storm-cloud-july-23-1.4738996