20 Dec 2022 | 09:26 AM UTC
US: Adverse winter weather forecast over northwestern regions through at least Dec. 22
Adverse winter weather forecast across parts of the northwestern US through at least Dec. 22. Hazardous travel conditions likely.
Event
Adverse winter weather is forecast across parts of the northwestern through at least Dec. 22. A winter storm system will move eastward over the Pacific Northwest and into the Northern High Plains Dec. 20-21, bringing heavy snowfall especially over mountainous regions. Snowfall accumulations of more than 30 cm (12 inches) are possible in elevated parts of the affected area. The heavy snow is expected to be accompanied by strong winds and will likely lead to hazardous driving conditions due to icy roads and reduced visibility. As the weather system moves through the area it will draw in extremely cold air behind it, leading to a significant drop in temperatures across the affected region. Another storm system is forecast to approach the northwest from Dec. 22.
Government Advisories
As of early Dec. 20, the National Weather Service (NWS) has issued winter storm warnings across parts of western, central, and eastern Washington, northern and southeastern Idaho, western Montana, and western Wyoming. Winter storm watches have been issued for parts of central and southeastern Idaho and winter weather advisories for parts of northern, western, northeastern, and southeastern Washington, western and northeastern Oregon, northern, central, and southeastern Idaho, and northwestern and western Wyoming. Wind chill warnings, watches, and advisories are also in effect across parts of the affected area. Officials could update and possibly extend the coverage of weather alerts over the coming days.
Hazardous Conditions
Snow accumulations are likely across the affected area, especially at higher elevations. 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 in some areas. Blizzard conditions are possible. Sporadic power outages could occur throughout the affected area.
Transport
The winter weather will likely cause ground and air transport disruptions over the coming days. Traffic and commercial trucking delays are possible along regional highways. Dangerous and challenging 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 highways if driving conditions become too hazardous. 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.
