Heavy rain, thunder gives a soggy start to Ontario's long weekend

With the Canada Day long weekend about to kick off, many folks in southern and eastern Ontario were probably hoping Wednesday's stormy afternoon would be the last bout of gloomy weather until next week. Unfortunately, as folks on the Prairies and in parts of northern Ontario can attest, there's more to come.

A low-pressure system has been drenching the Prairies since Thursday, causing localized flooding in some areas.

The system will crawl into northwestern Ontario on Friday, bringing a risk for thunderstorms across the region.

The system will continue to across northern Ontario throughout Friday, dragging the soggy weather to the rest of Ontario by Saturday. Don't be surprised to see some showers and hear a few rumbles of thunder overnight Friday.

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Multiple rounds of rain could soak Saturday plans

Southwestern Ontario will be the first to see widespread rain on Saturday morning.

Multiple rounds of showers and thunderstorms will track behind the morning's initial rainfall.

The rounds of rain will then reach the Greater Toronto Area (GTA) by midday and reach eastern Ontario by the afternoon.

The 401 corridor will be especially impacted by the rain, with 20-40 mm expected to fall. This could cause pooling on the major highway and reduce visibility in times of heavy rainfall. Be sure to exercise caution when travelling and drive accordingly.

Areas south of the 401, such as London and Niagara, will also see a thorough soaking of rain on Saturday.

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Moving farther north into cottage country, rain totals will begin to taper off, with just 5-20 mm expected through the weekend.

While the thunderstorms tracking behind the rain should stay non-severe in nature, there is a chance for stronger storms to develop towards the northeastern regions of the province. The main risks for any strong storms that develop will be strong winds and large hail.

Sunday will see drier weather across southwestern Ontario and the GTA, although showers will linger a bit longer in the province's eastern region.

Stay with The Weather Network for more forecast updates and information on your weather across Ontario.

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