Stormy weather to usher in cool relief for Ontario, Quebec

Residents of Ontario and Quebec experienced some of the worst heat and humidity of the week on Friday, but relief has come for the weekend, as cold front has been ushered in by a line of thunderstorms that produced torrential downpours, hail, strong winds and possibly a few tornadoes.

In cities across southern Ontario the mercury climbed into the low 30s during the day, with Windsor and Toronto reaching highs of 34°C. The humidity made those temperatures feel about 10 degrees warmer, though, approaching the danger zone for people to suffer from heat exhaustion and possibly heat stroke.

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Temperatures elsewhere in the province, and in southern Quebec, didn't reach quite that high, but they only missed by a degree or two, and conditions were just as hot, muggy, and potentially dangerous for those stuck in the heat without relief.

A Humidex Advisory was in effect for all of southwestern, south-central and eastern Ontario, due to humidex values in the low-to-mid 40s across the southern half of the province. Southwestern Quebec continued under a Heat and Humidity Warning, due to humidex values near 40.

Cities such as Windsor, London, Hamilton, and Ottawa had Heat Alerts in effect, and the City of Toronto extended their Extreme Heat Alert for yet another day. Cooling stations were set up in communities to help people get out of the heat.

As the approaching weather system swept through Ontario, thunderstorms kicked up ahead the system's cold front. With all of the heat and moisture around from this week, many of these storms developed into severe thunderstorms, with torrential rainfall, hail, powerful wind gusts, and there may have been a few tornadoes.

Environment Canada issued severe thunderstorm watches and warnings throughout southern Ontario and southern Quebec. Tornado watches were also in effect for all regions of Ontario around Georgian Bay, and into eastern Ontario, and tornado warnings were issued periodically as meteorologists detect rotation in storm cells on radar, or storm spotters see funnel clouds forming from especially strong storms.

There were reports of funnel clouds near Barrie, Innisfil and Brantford, but there were many more reports of storm damage — branches and trees down, damaged roofs, and power outages from downed lines. There were even reports of overturned cars in Gravenhurst and flipped trailers in Petawawa and Pembrooke. Wind gusts in excess of 100 km/h were reported in Waterloo and Hamilton, but given the damages suffered, these powerful wind gusts were likely experienced in many areas along the line of storms.

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After the muggy, stormy day on Friday, the cold front is bringing cooler, drier weather for Ontario and Quebec for the weekend. This should last well into next week giving everyone who was in the heat wave some much-needed relief after what they've endured over the past week.

(Photo courtesy: Canadian Press/Dave Chidley)

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