MONTREAL — A major storm that arrived in northern Ontario on Wednesday is forecast to bring significant snow to the province and to northern Quebec over the coming days — just in time for Environment Canada’s new colour-coded weather alert system.
The storm, which originated in the United States, will bring heavy snow, strong winds and lake effect snow activity, which occurs when cold air moves over warmer water, Environment Canada meteorologist Gerald Cheng said Wednesday.
Cheng, a warning preparedness meteorologist, said between 30 and 60 centimetres of snow is forecast in northeastern Ontario through Friday, while 10-20 cm is expected in northwestern Ontario, before the system moves through a large swath of northern Quebec.
The area of Quebec expected to be affected stretches from Waskaganish, a Cree community on the southeastern shore of James Bay, to Chibougamau. As well, Quebec’s North Shore, between the Manicouagan to Minganie regions, is also expected to be hit by inclement weather.
“This winter storm is already wreaking havoc in northern Ontario, already snow is falling for many parts and some routes are already closed,” Cheng told a briefing.
Strong winds up to 90 kilometres an hour are expected for Lake Erie and the northeastern shore of Lake Ontario.
The Greater Toronto Area could see strong winds up to 80 km/h through Friday morning and perhaps some flurries from lake effect snow.
No alerts are noted for southern Quebec, including the Montreal region.
The storm coincides with a change in Environment Canada’s national weather alert program, which is now using a colour-coded system of yellow, orange and red alerts to indicate risk level.
Cheng said the shift came after years of planning.
“We want to implement colour-coded weather alerts because we know it works and it’s recommended by the World Meteorological Organization,” Cheng said.
“Many other countries use it such as the United Kingdom, France, Switzerland, South Africa, New Zealand just to name a few, and for them it’s very effective in communicating risks to the population.”
For example, yellow alerts will be most common for hazardous, short-term weather events. Orange alerts are less common and likely to cause significant damage. A red alert is reserved for rare, dangerous and life-threatening events.
Northern Ontario, where up to 60 cm is expected, is on orange alert; the rest of the storm’s path is on yellow.
The agency says some examples of red alert weather events are the 1998 ice storm in Quebec and Ontario; an epic, record-breaking snowstorm in St. John’s, N.L., in January 2020; and the November 2021 atmospheric river in British Columbia that brought heavy rain and flooding, destroying roads and highways.
“We’re trying to communicate clearly to Canadians,” Cheng said, “but behind the scenes there’s a lot of work on the data to ensure that everything is running smoothly and showing correctly.”
Environment and Climate Change Minister Julie Dabrusin said in a statement, “We continue to experience more frequent and extreme weather in Canada, which makes it more important than ever for Canadians to have access to clear, accurate and easy-to-understand weather alerts.”
This report by The Canadian Press was first published Nov. 26, 2025.
Sidhartha Banerjee, The Canadian Press
