A tropical storm that has already caused significant damage in parts of South Carolina and the Gulf Coast of Florida is now moving northward, bringing heavy rainfall to eastern Ontario and western Quebec starting Thursday night.
Environment Canada has issued rainfall warnings for nearly all areas within this region, as the storm merges with a low-pressure system.
As of early Thursday afternoon, five specific warnings have been issued related to the remnants of Tropical Storm Debby:
- Gatineau Region: Rainfall is expected to be between 80 to 120 millimetres on Friday and early Saturday, with the possibility of reaching up to 140 millimetres.
- Western Quebec: Areas to the west of the Gatineau warning should expect 50 to 70 millimetres of rain.
- Northern Western Quebec: Communities north of Gatineau could see between 50 to 80 millimetres, with some spots possibly reaching 100 millimetres.
- Ottawa-Gatineau and East of Highway 416: Rainfall totals are expected to range from 50 to 100 millimetres Thursday night and Friday.
- Eastern Ontario: Areas including Brockville, Smiths Falls, and Renfrew may receive 50 to 75 millimetres of rain starting Thursday night.
No alerts have been issued for western Renfrew County. For instance, Deep River is only forecasted to experience showers with a risk of thunderstorms.
There is a potential for flash flooding and water pooling on roads, particularly in low-lying areas. Environment Canada also warns of a risk of thunderstorms accompanying the heavy rain Thursday night and into Friday.
While no local conservation areas have issued flood watches or warnings, the situation remains dynamic.
In Ottawa, the record for rainfall on August 9th stands at 41.4 millimetres, set in 1959. The all-time daily rainfall record for August is 71.1 millimetres, recorded on August 11, 1887.
Friday’s forecasted high is 22°C in Ottawa, though the humidity could make it feel closer to 30°C at its peak. The overnight low is expected to be around 16°C, with Saturday shaping up to be a sunny day with temperatures in the mid-20s.