UPDATE: Due to additional information sources this afternoon and tornado watches from Environment Canada, we have updated our Manitoba and Northwestern Ontario forecasts. The updated forecast for these regions can be found here: https://www.weatherwatch.space/post/update-tornado-watch-issued-severe-thunderstorms-expected-across-ontario-manitoba
We are watching the risk for severe thunderstorms across portions of Southern Ontario and Southern Quebec this afternoon and evening. Alongside this, we are also watching a second region in Southern Manitoba and Northwestern Ontario. Damaging winds, large hail and heavy rain are the main threats, although, an isolated tornado or two may be possible in these regions.
Southern Ontario/Southern Quebec:
Areas in orange and marked with a '4' can expect a strong risk for severe thunderstorms. In Ontario, this region extends from Tamworth and Kaladar eastward through to Renfrew and Hawkesbury including Perth and Ottawa. In Quebec, this region extends from Mont-Tremblant Park southwestward towards Duhamel and Gatineau. The main threats in this region include heavy rain over 40mm, damaging winds between 80 and 110km/h and moderate to large-sized hail between 1.5 and 2.5cm. An isolated tornado is also possible in this region.
Areas in yellow and marked with a '3' can expect a moderate risk for severe thunderstorms. In Ontario, this region extends from Oshawa through to Fenelon Falls, Madawaska and Deep River, including everything south of this line such as Bancroft, Pembroke, Peterborough, Belleville, Kingston, Brockville and Cornwall. In Quebec, this region extends from Fort-Coulonge through to Lac McLennan, Timbrell, La Tuque and Shawinigan, including Montreal and Huntingdon. The main threats in this region include heavy rain over 40mm, damaging winds between 70 and 100km/h, locally 110km/h and moderate to large-sized hail between 1 and 2cm. An isolated tornado is also possible in this region, although the best risk is near the Ontario/Quebec border extending into Quebec towards Obedjiwan.
Areas in green and marked with a '2' can expect a low risk for severe thunderstorms. In Ontario, this includes everything east of a line which extends from Delhi through to Brantford, Orillia and Stonecliffe. This includes Haliburton, Niagara Falls, Toronto and Hamilton. In Quebec, this includes areas between Dorval-Lodge, Obedjiwan, Portneuf, Quebec City, and Sherbrooke, including Stanstead. A pocket of isolated strong to severe thunderstorms may be possible around Lake Nipissing including West Nipissing and North Bay. The main threats in this region include heavy rain over 40mm, damaging winds between 70 and 90km/h, locally 100km/h and moderate sized hail near 1 to 1.5cm. An isolated tornado may be possible slightly further east in Quebec towards Sherbrooke and Portneuf, as well as further west in Ontario to include Stonecliffe, and Haliburton, although, due to the low risk of severe thunderstorm development, we have not included this in a higher level on our scale.
Elsewhere, areas in blue and marked with a '1' can expect non-severe thunderstorms.
Widespread severe thunderstorm watches have been issued across Southern Ontario and Southern Quebec including a few which states the potential for tornado development.
Storms will develop across this region in the morning, although, it's the afternoon storms which are of most concern.
Northern Ontario/Southern Manitoba:
Areas in yellow and marked with a '3' can expect a moderate risk for severe thunderstorms. In Ontario, this region includes Woodland Caribou Park through to Kenora and Nestor Falls. In Manitoba, this region extends from Atikaki Park through to Loon Straits and Riverton, continuing south towards Portage la Prairie and Cartwright. This region includes Winnipeg. The main threats in this region include heavy rain over 50mm, damaging winds between 70 and 100km/h, locally 110km/h and moderate to large-sized hail between 1 and 3cm. An isolated tornado is also possible in this region, mainly near the Ontario/Manitoba. The strongest tornado risk extends from Nopiming Park and Werner Lake through to Winnipeg and Ste. Anne, including Morris and Badger.
Areas in green and marked with a '2' can expect a low risk for severe thunderstorms. In Ontario, this includes an area extending from Pikganikum inland towards Uchi Lake and Sioux Lookout, extending to Fort Frances. This region includes Red Lake, Grassy Narrows and Dryden. It is questionable whether thunderstorms, especially severe storms, will even make it this far into Northern Ontario, although, the risk is there. A pocket of isolated strong to severe thunderstorms may be possible around Lake Nipissing including West Nipissing, North Bay and Temagami. In Manitoba, this risk extends south of a line which runs from Charron Lake through to Jackhead, Skownan and Benito. The main threats in this region include heavy rain over 40mm, damaging winds between 70 and 90km/h, locally 100km/h and moderate to large sized hail between 1 and 2cm. An isolated tornado is possible in this region, especially from Pikangikum through to Perrault Falls, including Red Lake. Despite the threats, due to the low development risk, we have not included this region in a higher level on our scale. Much of Southern Manitoba, especially southwestern Manitoba, will not likely see any storms due to how localized the thunderstorms are. Either way, we have still highlighted the area for the risk of one or two isolated severe thunderstorms.
Elsewhere, areas in blue and marked with a '1' can expect non-severe thunderstorms.
These thunderstorms will mainly affect this region from the late afternoon into the evening. We will be monitoring the risks and alerts issued today.
If conditions warrant an upgrade, we will upgrade to level 4 or 'strong' risk for severe thunderstorms later in the day for portions of Manitoba and Northwestern Ontario.
Southern Alberta/Southern Saskatchewan:
Isolated thunderstorms are expected across Southern Saskatchewan. An isolated severe thunderstorm or two can't be ruled out. Due to the low risk, we have not made a map for that region.
Across Alberta, isolated non-severe thunderstorms are expected. An isolated severe thunderstorm or two can't be ruled out. Due to the low risk, we have not highlighted an area of a low risk for severe thunderstorm development. Across portions of Central Alberta extending from Whitecourt and Fort Assiniboine through to Dapp, Viking, Killam, Donalda and Drayton Valley, including Edmonton, we are watching the risk for some cold core funnel clouds. On rare occasions, these funnels will briefly touch the ground creating a landspout tornado.
Tornado Threat Regions: please read the writeup for each region for exact locations and details about the threats.
- Central Ontario (Afternoon)
- Central Alberta (Afternoon and Evening)
- Eastern Ontario and Southern Quebec (Afternoon and Evening)
- Southern Manitoba/Northwestern Ontario (Evening)
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