US, Canada: Adverse winter weather likely across parts of western regions through March 2

Event

Adverse winter weather, including heavy snow and heavy rainfall, is forecast across parts of the West North Central and Northwest regions, US, and far southwestern Canada through at least March 2.

Government Advisories
As of late Feb. 27, the US National Weather Service has issued winter weather advisories over far northern Idaho, far northwestern Montana, and far northeastern Washington. Flood watches and warnings are in place across far northwestern Oregon and western and south-central Washington. Avalanche warnings are in effect for portions of the Washington Cascades, including Stevens, Snoqualmie, and White passes as well as the I-90 corridor.

The US Weather Prediction Center (WPC) has issued a "Slight Risk" of excessive rainfall for portions of the Washington and northern Oregon coastal range and the Washington Cascades through early March 1. Authorities have also warned of heavy snow across the Pacific Northwest through March 2. 20-30 cm (8-12 inches) of snow is forecast over northern Idaho and northwest Montana. More than 20 cm (8 inches) of snow is likely in the Washington Cascades and more than 15 cm (6 inches) of snow is possible over the northern Rockies.

The Meteorological Service of Canada has issued red (the highest level on a three-tier scale) winter storm warnings across Boundary, East Columbia, Kootenay Lake, Shuswap, West Columbia, and West Kootenay; up to 50 cm (20 inches) of snow is likely through Feb. 28 with freezing rain possible the evening of Feb. 28. Red rainfall warnings are also in place for Fraser Valley, Howe Sound, and Metro Vancouver; 5-7 cm (2-3 inches) of rain is forecast. Officials could update and possibly extend the coverage of the relevant weather alerts over the coming days.

Hazardous Conditions
Snow accumulations are likely across the affected area. Lesser accumulations are possible where sleet and freezing rain mix with the snow, and precipitation are less intense. In addition to the heavy snow, strong wind gusts will likely lead to periods of blowing and drifting snow. Blizzard conditions are possible. Sporadic power outages are possible throughout the affected area.

Transport
The winter weather will likely cause ground and air transport disruptions across the affected area over the coming days. Traffic and commercial trucking delays are possible along regional highways. Difficult and dangerous driving conditions are also likely on secondary and rural roads in the affected states 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 throughout the affected area. Flight delays and cancellations are likely due to ground stops and deicing operations at regional airports.

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. If routing shipments by truck through the affected area, plan accordingly for delivery delays. Confirm flights. Charge battery-powered devices in the case of prolonged electricity outages.

Resources

US National Weather Service
US Road Conditions
Meteorological Service of Canada