Mystery ‘twister’ cloud caused by burning, meteorologist says

A rotating cloud column rising into the sky near Hirsch was caused by a similar process that produces “dust devils” in the summer.

Joel Fortin shot video of the mystery cloud, set against a mostly clear blue sky, with onlookers describing it as a “twister.”

Brad Vrolijk, a meteorologist for Environment Canada, noted there was some burning in the field.

“What the fire would be doing is heating up the air near the surface very quickly which will cause it to rise and as it rises, air from the sides comes in to take its place and that area gets heated up quickly,” Vrolijk said.

“So as this happens, we develop this column of rising air that will start to spin a little bit. So as it rises, the water in the air condenses and you get this nice big smooth-looking column of rotating air lifting up.”

Dust devils occur during the peak summer when the sun is high and hot, Vrolijk said.

The sun heats the ground which in turn heats the air, causing it to rise. Cooler air takes its place, heats up and rises as well.

“They can make a bit of a mess of things and very strong ones have been known to lift some small objects like tents and things like that. But typically, they don’t do much damage,” Vrolijk said.

He found Fortin’s video an interesting spectacle.

“(It’s) unusual to see but if you have a decent enough fire at this time of year, (it’s) certainly possible,” he said.

Hirsch is about 30 kilometres east of Estevan.