A potent system has begun to filter onto the eastern Prairies Friday, bringing with it a good soaking for the drought- and wildfire-stricken region. Some areas could receive 50-75 mm, or even higher amounts, by the time it eases, so it will give a good dousing for the wildfires and dry conditions. However, the low-pressure system is also bringing the threat for severe weather, which includes damaging wind and supercell potential in Manitoba and northwestern Ontario, and a non-zero tornado risk Friday. The storm threat will push into northwestern Ontario Saturday. More this storm, below.
FRIDAY AND BEYOND: HELPFUL RAINS FOR THE EASTERN PRAIRIES, SEVERE STORM POTENTIAL
It's been a long time coming, but beneficial rains have started to infiltrate the eastern Prairies and will continue into Saturday.
A stateside low-pressure system has slide up the boundary into Manitoba, bringing some fairly heavy downpours into the province.
Heavy rain will continue to spread in Manitoba Friday through the morning and in northwestern Ontario in the afternoon, continuing into Saturday. Most of the rain will end by Saturday in Manitoba as the low pushes into northwestern Ontario.
This storm will produce widespread, drenching rains along its path. A large swath of southern Manitoba could see 50-75 mm of rain by the end of the storm. Some areas could see exceed 75 mm, aided by thunderstorms.
As well, there could be severe thunderstorms on Friday afternoon and evening across southern Manitoba and northwestern Ontario, potentially damaging wind gusts, small hail and heavy rainfall, of course. There is also the potential for supercells, away from populated centres, and a non-zero tornado risk.
The rains will bring significant relief to areas hit hard by the devastating drought that’s developed on the Prairies this summer. Much of southern Manitoba was in an “exceptional drought” as of the July 31, 2021, update of the Canadian Drought Monitor.
SATURDAY AND BEYOND: STORM RISK MOVES TO NORTHWESTERN ONTARIO, COOLER PATTERN EMERGES
Come Saturday, the system will regenerate north of Lake Superior in northwestern Ontario. Winds will be the main concern, with strong gusts expected, with a slight tornado risk but should remain north of Highway 17. Central Manitoba can expect to see some lingering showers as temperatures cool off in behind the system. The much cooler pattern will linger through next week.
The next system will bring another round of widespread rain to southern Saskatchewan and Manitoba Sunday through early Monday, as low-pressure system tracks from Montana to southern Manitoba and then into northwestern Ontario.
Another low is expected to develop over Alberta on Sunday and then move east across the Prairies Monday and Tuesday with widespread rain. Additional unsettled weather is possible late week.
Check back for the latest conditions across the eastern Prairies.