US: Winter storm forecast over Southwest, West North Central, and Upper Midwest regions through at least Feb. 23

Event

A significant and long-duration winter storm is forecast to impact parts of the Southwest, West North Central, and Upper Midwest regions through at least Feb. 23. Forecast models indicate that the storm is likely to impact areas of the Plains into the Great Lakes with a mixture of snow, sleet, and freezing rain that may come in two waves. Heavy snowfall and the increasing wind are likely to lead to significant blowing and drifting of snow. Near blizzard conditions are possible over parts of North Dakota and South Dakota. Authorities are discouraging travel through Feb. 22. Snowfall totals of more than 15 cm (6 inches) are forecast from the Dakotas into the western Great Lakes, with more than 30 cm (12 inches) possible in some areas. Significant ice accumulations of more than 0.6 cm (0.25 inches) are possible across the Upper Midwest and Great Lakes from the evening of Feb. 21. Very cold air is likely through at least Feb. 25, with temperatures near record low values and dangerously cold wind chills in the Plains.

Government Advisories
As of late Feb. 20, the US National Weather Service (NWS) has issued winter storm warnings for parts of western Colorado, central Minnesota, western and southern Montana, southern North Dakota, northern South Dakota, northwestern Wisconsin, and south-central Wyoming. Winter weather advisories are in place for northern Idaho, the rest of Minnesota, the rest of Montana, the rest of South Dakota, much of Utah, the rest of Wisconsin, and the rest of Wyoming. Officials have issued winter storm watches for much of Michigan. Authorities will likely issue new alerts or update/rescind existing advisories as the winter storm transits the region over the coming days.

The NWS's Weather Prediction Center has warned of two waves of heavy snowfall across the Northern Plains through the Great Lakes through Feb. 23. Heavy snow is likely from southwestern Montana to the Upper Peninsula of Michigan while significant icing is forecast from the mid-Mississippi Valley to northern Lower Michigan. Snow accumulations of more than 10 cm (4 inches) are forecast over southern South Dakota and the northern tier counties of North Dakota, through central Minnesota, and into northwestern Wisconsin and the western Upper Peninsula of Michigan, with locally heavier totals of more than 20 cm (8 inches) along the eastern North and South Dakota border into central Minnesota through early Feb. 22. Additional heavy snow is likely from the northern South Dakota-Minnesota border across central Minnesota into northwestern Wisconsin and the western Upper Peninsula of Michigan through early Feb. 23 while ice accumulations of more than 0.25 cm (0.1 inches) are likely across parts of southern Wisconsin and central Lower Michigan over the same period.

Heavy snow is also forecast across the Southwest region through Feb. 23. Snow accumulations of more than 20 cm (8 inches) are likely across the Elk and San Juan mountains from late Feb. 21 through Feb. 22. From late Feb. 23 through Feb. 24, heavy snow of more than 20 cm (8 inches) is likely to continue over the western Colorado ranges, especially across the San Juan and Elk mountains as well as over the southern Utah mountains and Mogollon Rim in Arizona.

In addition to the precipitation, strong wind gusts could lead to periods of blowing and drifting snow. Sporadic power outages are likely throughout the affected area.

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. Confirm flights. Charge battery-powered devices in the case of prolonged electricity outages.

Resources

US National Weather Service
US Road Conditions
Weather Prediction Center