Colorado Low to impact the Northern Plains with snow, rain and wind: what you need to know
BISMARCK, N.D. (KFYR) - A Colorado Low is taking shape in the Rockies on Tuesday evening and will quickly move north and impact North Dakota and eastern Montana Tuesday night through early Thursday morning, with the greatest impacts during the day on Wednesday.
The latest forecast information suggests that temperatures will be slightly cooler Tuesday night through Wednesday, allowing for more of the precipitation in extreme western North Dakota and eastern Montana to fall as snow.
However, a cold rain will be the predominant precipitation type for most of North Dakota, with a widespread swath of one to two inches and some locally higher amounts of rain possible.
In terms of total moisture from this system, the greatest amounts will fall in southwest North Dakota. However, some of this moisture will be in the form of snow in that specific region.
Now, focusing on the winter weather aspect of this Colorado Low. Temperatures will be crucial to monitor as they will determine exactly where the rain/snow line sets up. A few miles will be the difference between rain and snow, which will lead to a sharp gradient in snow amounts.
Ground surfaces are still rather warm, but with periods of higher snowfall rates and cold air funneling in from the north, accumulation is likely, especially on grassy surfaces, with roads possibly becoming slushy to treacherous at times.
A winter storm warning has been issued in North Dakota for Golden Valley, Slope and Bowman counties for snow accumulations of five to nine inches, with locally higher amounts possible across elevated terrain along the Montana border. This warning lasts until 9 p.m. MDT Wednesday.
A winter storm warning is also in effect for all of southeast Montana for snow accumulations of six to 12 inches, with locally higher amounts possible. This warning lasts until 6 p.m. MDT Wednesday.
Additionally, winter weather advisories are in effect for Daniels, Sheridan and Roosevelt counties in Montana as well as Divide, Williams, McKenzie and Billings counties in North Dakota for two to four inches of wet snow expected.
Here’s the First Warn weather team’s latest thinking with the snow forecast, which will be highly dependent on how much cold air moves into the western side of this system. A swath of 4-6″ of snow is likely in southwest North Dakota and southeast Montana, with up to 10″+ possible in some localized regions.
Lesser snowfall amounts of 1-3″ are more likely in northwest North Dakota and northeast Montana, with the greatest uncertainty being how far east the snow can accumulate. The circled region on the map indicates where this uncertainty exists, but updates to the forecast Tuesday night will provide some more clarity as to if these regions will see accumulating snow.
Another major component of this Colorado Low is the strong winds. A wind advisory is in effect for practically all of central and western North Dakota due to 45 mph wind gusts throughout Wednesday. Sustained winds will also be between 20-30 mph throughout the day.
There have already been power outages in the Sheridan, Wyoming and Miles City, Montana areas as of Tuesday evening due to the snow that has fallen there combined with the fact that leaves are still on many trees downing more branches.
Power outages are possible throughout central and western North Dakota due to the strong winds, but they will be more likely in regions where snow accumulates.
This system will wrap-up quickly on Thursday morning with possibly a few lingering showers early on, while the winds will remain strong, gusting up to 35 mph during the day.
Stay tuned to Your News Leader and your First Warn weather team for updates throughout the week.
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