Northern Ontario: Thunderstorm Outlook for Sunday, September 19, 2021

Forecast Discussion

Thunderstorms are expected to develop over Minnesota and track into Northwestern Ontario late in the day on Sunday. There is some uncertainty about the timing of when these storms will reach our side of the border which will determine the exact risk they will pose to the region. If they show up earlier, the environment would be favourable for a few of these storms to bring some severe threats including strong wind gusts, large hail and heavy rainfall. The tornado risk is fairly low, but can’t be completely ruled out. Storms will continue late in the evening and overnight with the isolated severe risk still present mainly due to some flash flooding concerns. More storms are possible on Monday across Northern Ontario.