Thunderstorm watches, warnings across GTA

Environment Canada has issued rainfall warnings and thunderstorm watches for the GTA as another day of hot and humid conditions brings a risk of storms and heavy downpours for the region on Tuesday.

A rainfall warning and a thunderstorm watch are in effect for Toronto, Mississauga, Brampton, Vaughan, Richmond Hill, and Markham. These areas were previously under a thunderstorm warning earlier in the morning.

“Heavy rain is expected this morning with showers and thunderstorms. Total rainfall amounts of 50 to 75 mm are possible with rainfall rates of 40 mm within an hour,” the National Weather Agency states in its rainfall warning.

Environment Canada warns that heavy downpours can cause flash floods and water pooling on roads.

In Toronto, traffic cameras show flooding on the Gardiner Expressway west of Jarvis Street, as well as Lake Shore Boulevard in the eastern and western sections of the roadway.

The Toronto and Region Conservation Authority (TRCA ) has issued a flood watch, warning of increasing water levels in water bodies and watercourses within its jurisdiction.

“Current weather forecast suggests flooding from river systems is possible in TRCA watersheds due to heavy rain and thunderstorm risk that could lead to high runoff, flooding or erosion.”

Other areas of the GTA are just under a thunderstorm watch, which was downgraded from an earlier warning.

“Thunderstorms are tracking eastward over southern Ontario and may produce isolated damaging wind gusts, torrential downpours and large hail. Thunderstorms will move east of the area by midday, however, the threat of heavy rain will persist for much of the day,” Environment Canada says.

The storms, which arrived in the morning and could continue into the afternoon, could bring heavy rain and produce wind gusts of up to 90 km/h, accompanied by nickel-sized hail.

680 NewsRadio Toronto meteorologist Jill Taylor says the risk of thunderstorms will last until around 2 p.m.

On Monday, downpours and thunderstorms led to flooding in some areas across the GTA.

Environment Canada had previously issued a heat warning for most of southern Ontario over the weekend. That alert ended Monday but could be reissued on Tuesday, as temperatures are expected to reach 28 C but feel more like 38 with the humidity.

Taylor says refreshing air is on the way for Wednesday and the rest of the week with temperatures ranging from the mid- to high-20s.

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