Southern Ontario: Thunderstorm Outlook for Wednesday, June 9, 2021

Forecast Discussion

A cluster of slow-moving thunderstorms could develop through parts of Southwestern Ontario during the afternoon and early evening on Wednesday. These storms will be similar to what we’ve seen over the past few days so they should be the typical garden variety non-severe storms. However, due to the slow-moving nature of these storms, it could produce some localized flooding if a region gets stuck under one of these cells for a few hours. The main area of concern for this flooding potential is through the London, K/W and Brantford area along with Huron and Perth counties. This is where the latest data indicates most of the storms will develop although this zone may shift around depending on how the environment materializes. Storms will quickly fizzle out after sunset once the daylight heating that was fuelling them disappears.