A powerful storm tore through southern Ontario Saturday, toppling trees, cutting electricity and prompting multiple afternoon tornado warnings.

Environment Canada issued more than 20 severe thunderstorm watches for cities across southern Ontario, including Toronto, Hamilton, Kingston, London, Niagara and Waterloo. The risk of thunderstorms was expected to last late into Saturday night.

The weather system arrived in Toronto in the early afternoon and pummeled the city with sheets of rain, which helped break the city’s dense, humid heat. At least 6,800 Toronto Hydro customers were without power in the city’s west end Saturday afternoon, and there were multiple reports of downed trees.

Residents across southern Ontario reported serious damage to their homes and vehicles amid the intense winds. Environment Canada sent a worker to survey damage and assess whether a tornado touched down in the Oshawa area.

A woman living in Brampton told CTV Toronto that she ran to her basement to seek cover when the powerful winds hit.

“It was a very scary experience,” she said.

A Brampton man said part of his roof was torn up by the winds and that his patio set is now gone.

“Right now my house is completely flooded inside with rain,” he said.

The intense weather activity was captured online by Twitter users:

Fun storm we are having in #Toronto. pic.twitter.com/61AjeMdEhC — Mike Boers (@mikeboers) August 13, 2016

Lots of trees down in Leaside with at least one road closed @CP24 #storm #toronto pic.twitter.com/cxChf0EGoU — Allyson Scott (@snaphappychick) August 13, 2016

Took this a few min ago storm moving into Trenton, streets are flooding with torrential rain now. #onstorm #onwx pic.twitter.com/oxJCAdOQMf — Chris Partridge (@Hype3R) August 13, 2016