We are currently watching the risk for some severe thunderstorms across portions of Saskatchewan and Eastern Alberta as well as Southern Manitoba and Northwestern Ontario.
Southern Manitoba:
We are watching the risk for widespread severe thunderstorms across portions of Southern Manitoba as a bowing segment of storms will likely pass from Saskatchewan into Manitoba. Alongside this risk, some isolated severe thunderstorms are possible further north in the province.
Areas north of a line which extends from Little Grand Rapids through to Gunisao, Norway House and Clearwater Lake Park can expect some scattered showers and non-severe thunderstorms. Heavy rain is the main threat. This is highlighted in the non-severe thunderstorm region in blue or marked with a '1'.
Areas between a line which extends from The Pas through to Warren Landing and Atikaki Park, as well as a line from Big Whiteshell Lake through to Princess Harbour and Lake Winnipegosis, can expect a low risk for severe thunderstorms. Most of these thunderstorms should remain non-severe with heavy rain and gusty winds between 50 and 70km/h. Small hail is possible. An isolated severe thunderstorm or two may develop in this region with gusty winds although, the risk is low. This is highlighted in the low severe thunderstorm region in green or marked with a '2'.
Areas between a line which extends from Swan River through to Reindeer Lake and Bloodvein down towards Big Whiteshell Lake and a line which extends from Buffalo Point over to O'Hanly, Oakview and Shoal Lake can expect a moderate risk for severe thunderstorms. These thunderstorms will mainly be isolated severe although a few areas could be impacted by some scattered severe thunderstorms. The main threats are heavy rain over 50mm, moderate hail between 1 and 2cm and gusty winds between 80 and 110km/h. This is highlighted in the moderate severe thunderstorm region in yellow or marked with a '3'.
Areas south of a line which extends from Shoal Lake through to Oakview, Riverton and Buffalo Point can expect a strong risk for severe thunderstorms. This includes Brandon and Winnipeg. The main threats with these storms are 50mm of rain or more, large hail between 2 and 5cm, locally higher in isolated cells and gusty winds between 90 and 120km/h. The hail sizes will decrease the further east as a wind threat will become more dominant. An isolated tornado or two can't be ruled out in this region, especially south of Brandon near the Saskatchewan and United States border. This is highlighted in the strong severe thunderstorm region in orange or marked with a '4'.
There is a notable amount of 'CIN' which is a severe thunderstorm parameter which can limit storm development. This could reduce the severe risk across Southern Manitoba.
Southern Saskatchewan:
=We are watching the risk for scattered thunderstorms, some severe, across portions of Southern Saskatchewan alongside some isolated severe thunderstorms further north.
Areas between Sturgeon Landing and Mountain Cabin extending south towards Melford, Moose Jaw, Coronach, Tisdale, and Lanigan can expect some non-severe thunderstorms. Heavy rain is the main threat. Small hail and at times, gusty winds, are also possible. This is highlighted in the non-severe thunderstorm region in blue or marked with a '1'.
Areas between a line which extends from Wildcat Hill Park over to Warson and Coronach, as well as a line from Coronach through to Milestone, Springside and to the south of Elbow Lake, can expect a low risk for severe thunderstorms. This region includes Regina. Most of these thunderstorms should remain non-severe with heavy rain and gusty winds between 50 and 70km/h. Small hail is possible. An isolated severe thunderstorm or two may develop in this region with gusty winds and marginally large hail although, the risk is low. This is highlighted in the low severe thunderstorm region in green or marked with a '2'.
Areas between a line which extends from areas south of Elbow Lake over towards Springside and Indian Head down towards Minton and a line which extends from Whitewood over to Estevan can expect a moderate risk for severe thunderstorms. This region includes Yorkton. These thunderstorms will mainly be isolated severe although a few areas could be impacted by some scattered severe thunderstorms as a line of severe thunderstorms forms and begins to 'bow'. The main threats are heavy rain over 50mm, moderate sized hail between 1 and 2cm and gusty winds between 80 and 110km/h. Briefly larger hail towards 3cm may be possible. This is highlighted in the moderate-severe thunderstorm region in yellow or marked with a '3'.
Areas south of a line which extends from Estevan over to Moosonmin can expect a strong risk for severe thunderstorms. The main threats with these storms are 50mm of rain or more, large hail between 2 and 5cm, locally higher in isolated cells and gusty winds between 90 and 110km/h. Stronger wind gusts are possible as these storms begin to merge and 'bow'. An isolated tornado or two can't be ruled out in this region, especially south of near the United States and Manitoba borders. This is highlighted in the strong severe thunderstorm region in orange or marked with a '4'.
The Saskatchewan forecast map attached DOES NOT include the severe thunderstorms forecasted towards the northern portion of the province.
Northern Ontario:
We are watching the risk for isolated thunderstorms, some severe, across portions of Northwestern Ontario as storms move from Manitoba into Ontario.
Much of Northern Ontario can expect some non-severe thunderstorm during the evening/overnight between Saturday and Sunday and into the day on Sunday. The main threats would include heavy rain and small hail. Gusty winds between 30 and 60km/h are also possible. This is highlighted in the non-severe thunderstorm region in blue or marked with a '1'.
Areas between a line which extends from Woodland Caribou Park over towards Dryden and Atikokan, as well as a line from Kenora through Sioux Narrows and Mine Centre, can expect a low risk for severe thunderstorms. Most of these thunderstorms should remain non-severe and sub-severe with heavy rain and gusty winds between 60 and 80km/h. Small to moderate sized hail is possible in the range of 0.5 to 1.5cm. An isolated severe thunderstorm or two may develop in this region with gusty winds and marginally large hail although, the risk is low. This is highlighted in the low severe thunderstorm region in green or marked with a '2'.
Areas south of a line which extends from Kenora through to Mine Centre and the United States border in Quetico Park can expect a moderate risk for severe thunderstorms. This region includes Fort Frances. These thunderstorms will mainly be isolated severe following the much larger severe threat from Manitoba although a few areas could be impacted by some isolated severe thunderstorms as a lingering cluster of sub-severe or severe thunderstorms pushes from Manitoba into Ontario. The main threats are heavy rain over 50mm, moderate sized hail between 1 and 2cm and gusty winds between 80 and 100km/h. Briefly larger hail towards 2.5cm may be possible although unlikely. This is highlighted in the moderate-severe thunderstorm region in yellow or marked with a '3'. An isolated tornado may be possible as these storms begin to isolate themselves as the storm line weakens. The best risk will be around Lake of the Woods.
There is a notable amount of 'CIN' which is a severe thunderstorm parameter which can limit storm development. This could reduce the severe risk across Northwestern Ontario from the Manitoba storms.