Message: Possible thunderstorms may cause flash flooding and pooling on roads
Environment and Climate Change Canada has issued a Special Weather Statement due to a risk of thunderstorms this evening, with further thunderstorms forecast for tomorrow. Thunderstorms are capable of producing heavy downpours that could cause flash flooding, water pooling on roads, and localized flooding in low-lying areas.
Forecasts are showing rainfall amounts of 15 mm to 60 mm possible tonight, with the potential for peak rainfall rates of 30 mm to 50 mm per hour. Risk of severe thunderstorms continues through tomorrow, with rainfall amounts of up to 80 mm and peak rainfall rates of 40 mm per hour possible. By late Friday night. some areas could see more than 100 mm of rain accumulation, especially if hit by multiple thunderstorms. Due to the isolated and sporadic nature of these thunderstorms, the ability to predict the amount of rainfall for specific locations is low.
Water levels may elevate into natural floodplain areas and low-lying roadways may be impacted. Soils could be saturated from the rain and may contribute to ponding, increased runoff into watercourses, and possible increased erosion and seepage issues. High amounts of rainfall in a short period of time can lead to increased runoff and flash flooding, particularly in urban areas. Local rainfall amounts could be higher due to the isolated nature of thunderstorms.
Individuals are reminded to avoid watercourses and flooded areas due to dangerous conditions, slippery banks and swift moving water. Children and pets should be kept away from the water.
The Conservation Authority continues to monitor watershed conditions and will issue advisories to municipalities and media should flood issues arise. Municipal emergency response staff and road superintendents should monitor local conditions closely. Please continue to monitor active weather alerts from Environment Canada.
This message will remain in effect until 12 p.m. on June 28th, 2025, unless otherwise updated.
