Southern Ontario: Thunderstorm Outlook for Thursday, August 12, 2021

Forecast Discussion

A line of nocturnal storms over Michigan could bring some isolated severe risk to Deep Southwestern Ontario during the early morning on Thursday. The main threat will be damaging wind gusts up to 90km/h along with lots of lightning. Later in the day, there could be some popup isolated thunderstorms through parts of Eastern Ontario although it’s very questionable. It’s possible that we see no storm activity on Thursday besides the morning storms. If we do see some storm development in Eastern Ontario then we can’t rule out the potential for one or two storms to briefly reach severe levels with moderate-sized hail and strong wind gusts. The tornado risk is pretty low, but as usual, we can’t rule it out with any severe weather. There could be some more storms early Friday morning and later in the day, but the exact location is unclear at this point.