Why Environment Canada got Montreal’s snowstorm forecast wrong

Montreal didn't have to wait long for its first major snowfall as it began on Nov. 10, 2025 and continued overnight.

Environment Canada says it didn’t expect a snow band to shift as far west as it did overnight Monday, dumping up to 20 centimetres of snow on Montreal — nearly four times what forecasters had predicted.

“We were caught off guard by the amount of snow in Montreal, which was greater than expected across the greater Montreal area,” said Julien Pellerin, meteorologist with Environment Canada, in an interview with CJAD 800 Radio.

“Initially, we expected the 15-to-20-centimetre band to be much farther east, over the Eastern Townships region,” he said. “However, that band shifted a little bit more west over the Montreal area.”

READ MORE: Heavy snow causes widespread power outages, school closures across Quebec

As a result, downtown Montreal saw about 20 centimetres of snow, compared with the five centimetres originally forecast. At Trudeau airport, eight centimetres were recorded. Meanwhile, areas such as Coaticook in the Eastern Townships — which had been expected to receive the heaviest snowfall — saw less than 10 centimetres.

The heavier-than-expected snow led to widespread power outages, school closures, and treacherous driving conditions across southern Quebec. Hydro-Québec reported more than 200,000 customers without electricity at the height of the storm, as wet, heavy snow weighed down tree branches and power lines.

Snow continued through Tuesday afternoon, with Pellerin saying Montreal could see another five centimetres before it tapers off.

“Fortunately, it’s not going to be the same wet, heavy snow we had during the previous night which put a lot of stress on the electric infrastructure,” he said. “It’s going to be a lighter snow, but we’re still expecting slushy conditions on the roads.”

The storm forced schools to close in several regions, including the Eastern Townships, Montérégie, the Laurentians and Montreal.

By late afternoon, some 1,000 Hydro-Québec workers were on the ground to restore service, a job that’s especially difficult because there are still some leaves on the trees that make the snow even heavier.