Torrential rain to hit Montreal as Quebec gets remnants of tropical storm Debby

Heavy rain is expected in Montreal on Friday, as the remnants of tropical storm Debby reach Canada.

Showers and possibly thunderstorms are expected to develop overnight Thursday and will pick up in intensity throughout Friday, says Jennifer Smith, a national warning preparedness meteorologist with Environment Canada. 

“It does taper through the night so that it’s clear of the Montreal region by Saturday morning,” she said.

In total, Montreal is expected to see between 60 and 80 millimetres of rain over this period. The city’s rainfall average for the whole month of August stands at 94.1 millimetres.

Other regions in Quebec can expect close to 100 millimetres such as the Outaouais, Lanaudière, Laurentians, Mauricie and Charlevoix. 

Environment Canada has issued a rainfall warning for most of southern Quebec.

Heavy showers in a short period of time combined with the already rain-water saturated soil means there are risks of localized flooding depending on the environment and drainage conditions, says Smith. 

She says people need to be “weather-aware” and mindful of low visibility and pooling on the roads, for example, given the combination of rain and winds of 20 to 30 km/h. 

Tropical storm Debby is currently above South Carolina and climbing up eastern United States. Six people have died in the storm so far.

Research scientist with Environment Canada Nathan Gillett says extreme precipitation events in North America have intensified this summer and are projected to increase in the future with climate change. 

“As the atmosphere gets warmer it can hold more moisture,” he said.

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