US, Canada: Storm system to bring heavy snowfall, strong winds to interior New England, US, and southeastern Canada, December 5-7

Event

A strengthening, low-pressure system will bring heavy snowfall and strong winds to portions of the New England region of the US, as well as southeastern Canada, Dec. 5-7. The affected areas include New York's eastern Adirondack Mountains, Vermont, New Hampshire, northern and western Maine, and western and central Massachusetts in the US, as well as southeastern Quebec and northern New Brunswick in Canada. Forecast models indicate the precipitation will initially begin in western Massachusetts around midday on Dec. 5 before spreading across the rest of New England by that late evening while becoming steadier throughout the day. Precipitation will then arrive in Quebec and New Brunswick, Dec. 6. The storm system should depart New England by the evening of Dec. 6 and Canada by midday Dec. 7. Snowfall rates may exceed 2.5 cm (1 inch) per hour in the hardest-hit areas. There is still significant uncertainty in the forecast at this time, as computer guidance is highly varied on the track; a track farther east will extend the swath of heavy snow to the south and east in the US and Canada, while a track farther west will allow the snow to mix with or change over to freezing rain or rain in some locations, limiting accumulations. Changes to the forecast are possible over the coming days depending on the track of the system.

Government Advisories
As of the afternoon of Dec. 3, the US National Weather Service (NWS) has issued winter storm watches for western Maine, all of New Hampshire, southern Vermont, and northern and western Massachusetts. Additionally, Environment Canada has issued special weather statements for heavy snow, strong winds, and freezing rain across southeastern Quebec. Authorities may issue new alerts or update/rescind existing advisories as the winter storm transits the region over the coming days.

Hazardous Conditions
The latest forecast guidance indicates the most snow will fall in western Maine and northern New Hampshire, where 25-45 cm (10-18 inches) are expected. 15-25 cm (6-10 inches) are expected in Vermont, the Berkshire Mountains of Massachusetts, northern New Brunswick, and southeastern Quebec. Between 7.5-15 cm (3-6 inches) are forecast in New York's Adirondack Mountains, southern New Hampshire, central New Brunswick, and interior southeastern Quebec. Lower amounts are expected farther south and east in Maine and Massachusetts in the US, and New Brunswick, Canada where the snow will likely mix with or change over to rain or freezing rain. Strong wind gusts could lead to periods of blowing and drifting snow. Blizzard conditions are possible. Sporadic power outages are possible throughout the affected area.

Transport
The inclement weather will likely cause widespread ground and air transport disruptions across the affected area through at least Dec. 7. Traffic and commercial trucking delays are possible along regional highways, including portions of the I-87, I-89, I-90, I-91, I-93, and I-95 corridors in the US, as well as the Trans-Canada Highway, the Autoroute Jean-Lesage, and the Autoroute Felix-Leclerc in Canada, Difficult and potentially dangerous driving conditions are also likely on secondary and rural roadways as maintenance crews prioritize clearing major routes. Authorities could close stretches of highway if driving conditions become too hazardous. Gusty winds may threaten to topple high-profile vehicles. Heavy wet snow and strong winds could bring down power lines and trees with foliage. Flight delays and cancellations are likely due to ground stops and deicing operations at regional airports, including those serving Montreal (YUL), Quebec City (YQB), and Burlington (BTV).

Advice

Monitor local media for updated weather information. Verify road conditions before driving in areas where heavy snowfall is forecast. Allow extra time to reach destinations in these areas and carry an emergency kit and warm clothes if driving is necessary, especially on secondary or rural routes that could become impassable. Plan accordingly for delivery delays if routing shipments by truck through the affected area through at least Dec. 3. Confirm flights. Charge battery-powered devices in the case of prolonged electricity outages.

Resources

National Weather Service
US Road Conditions
Meteorological Service of Canada