Significant freezing rain possible across the Montreal region by Wednesday

Forecasters are watching a storm system that could bring significant freezing rain to the Montreal region on Wednesday. The event may be similar to the April 2023 Ice Storm. (Valley Weather)

Special Weather Statement for significant freezing rain on Wednesday.

By now many of you may have read on social media of the possibility of a significant ice storm on Wednesday for portions of southern Quebec and the Ottawa Valley. The possibility does exist, but it is a rather complicated forecast. The event is shaping up similar to the April ice storm of 2023. 

Very warm air will prevail for the Montreal region to start the week, with highs surging into the teens for Monday and Tuesday. Strong southwest winds will develop on Monday, gusting up to 70km/h at times. The warm temperatures will rapidly melt the snow and ice pack, contributing to the ongoing flooding occurring along portions of the Châteauguay River as well as other locations. Flood warnings have been issued for several municipalities in southern Quebec, Ontario and northern New York. Pay close attention to what your local municipal officials are telling you regarding ice jams and rising water.

Ice jam flooding along the Châteauguay River in Châteauguay on Sunday. Flooding was also occurring in Huntingdon and points south as rapid snowmelt continues due to the very warm temperatures. (Ville de Châteuguay) 

By Wednesday, deepening low pressure over the central Unites States will move northeast towards the Great Lakes, while Arctic high pressure to the north will begin to drain cold air into the St. Lawrence Valley. Temperatures will fall towards the freezing point by early Wednesday morning, as precipitation begins to overspread the region from the south.

At this time a very pronounced thermal boundary will traverse the region close to the US border, with freezing rain and snow to the north and plain rain falling to the south. Where that boundary establishes itself will determine who receives the freezing rain. Precipitation amounts will be significant from eastern Ontario across southern Quebec into northern New Brunswick, with 20-40mm of rain possible. If just half of that fell as freezing rain, we would have significant impacts. Further north heavy snow and blowing snow are likely.

Stay tuned to future forecasts and weather warnings that will be issued as the event unfolds. Prepare now for what could be a significant weather event in Montreal, with perhaps tree damage and prolonged power outages. Travel may be greatly impacted on the road and in the air through Thursday.

Behind this storm, more wintry weather is possible, as temperatures drop below freezing through the weekend, with snow possible by Sunday.