Some parts of the Ottawa-Gatineau region could see as much as 35 centimetres of blowing snow from Monday night to Wednesday morning, causing Environment Canada to issue a winter storm warning.
The temperature in Ottawa is expected to drop to as low as -10 C as the wind gusts between 30 and 50 kilometres per hour.
The snow, at times heavy and blowing, is expected to begin falling around midnight.
The City of Ottawa said in a statement that snowplows will focus overnight on clearing and salt application on Highway 174, the Transitway and other major routes and collectors.
Plowing on gravel roads is expected to begin early Tuesday morning, and "priority sidewalk units" will also be deployed, the city said.
Check the City of Ottawa's online "Where is my plow" tracker for the latest.
Warnings for Outaouais, Brockville, Kingston
The warning issued for the Outaouais Monday morning said a storm coming from Texas will bring snow and blowing snow in some areas starting Monday night, with 20 to 35 centimetres of snow expected by Wednesday morning.
Gatineau and much of eastern Ontario's warning gives notice of "adverse weather conditions", with the forecast calling for five to 10 centimetres of snow overnight and another 15 to 25 centimetres on Tuesday, with gusts of up to 50 kilometres an hour.
The Brockville and Kingston areas are under a special weather statement instead of a winter storm warning, with a forecasted 10 centimetres of snow overnight before changing to ice pellets, then likely rain on Tuesday.
This is forecasted to be the first major winter storm of the season, with only trace amounts of snow falling in Ottawa-Gatineau until this past weekend — and warm weather records being broken up until Christmas Eve.