BOZEMAN – One of the strongest winter storms of the season arrives this weekend and big weather pattern changes. Near record highs on Saturday in the 50’s to lower 60’s and accumulating snow with hazardous travel by Sunday.
Saturday will be a high wind event across the state. Both sides of the divide will likely see strong to extreme winds with gusts between 50 to 80 mph. High wind prone areas along the Rocky mountain front will likely see the strongest peak wind gusts along with the upper Yellowstone region near Livingston.
SW Montana will see surface winds increasing by late afternoon 20 to 40 mph and with a strong cold front there could be peak gusts 40 to 50 mph. High wind prone areas like: Whitehall, Ennis, Twin Bridges, Three Forks, and Norris Hill will be favored for the strongest peak gusts. Ridge tops locally could also see gusts between 50 to 60 mph above 6,000’. This will produce considerable blowing snow in the backcountry and wind loading along ridge lines.
The National Weather Service has a WIND ADVISORY up for the Butte/Blackfoot region Saturday 1 pm to 8 pm. This is the window for a strong cold front to punch through this region.
Sustained winds will be increasing by late afternoon 30 to 40 mph and at times gusting to nearly 60 mph.
The National Weather Service has a HIGH WIND WARNING up for Jefferson and Meagher counties from 9 am to 11 pm Saturday.
SW Winds will increase to 35 – 45 mph and gusts to 65 mph are possible in Jefferson and Meagher counties.
The National Weather Service has a HIGH WIND WARNING up for upper Yellowstone region near Livingston, Big Timber, and Harlowton now through 6 am Sunday.
Sustained wind 30 to 50 mph and gusts up to 75 mph are possible. Strong crosswinds will produce hazardous travel on I-90 near Livingston for high profile vehicles. Power outages are also possible.
SATURDAY NIGHT INTO SUNDAY
A strong cold front will sweep across Montana from NW to SE Saturday afternoon into Sunday morning. Ahead of this front extreme wind will impact Montana Saturday morning into Saturday night. The front will produce increasing snow and wind Saturday evening into Sunday morning.
Southern Montana will see a longer duration snow event beginning Saturday evening through most of Sunday and may not end until Monday morning. This means areas of moderate to heavy snow is possible for the southern half of Montana.
The National Weather Service did issue a WINTER STORM WATCH for Beaverhead, Madison, Gallatin counties and the backcountry region near Cooke City Saturday night through Sunday night. This watch means conditions look favorable for significant impact to our region. This watch will be upgraded by Saturday morning to either a winter weather advisory or a winter storm warning.
NWS snowfall forecast is around 4” – 8” for most valleys and 8” – 12” over most mountains and passes. Around Cooke City there could be 1 to 2 feet of mountain snow.
Snow and gusty winds will produce localized blowing snow and reduced visibility Sunday into Monday morning.
Total snowfall will be highly varied across SW Montana. Forecast models show lower accumulations west of the divide near Butte and Anaconda. Heaviest snowfall should be east of the divide, especially in the Bozeman, Big Sky, West Yellowstone, Cooke City areas. Dillon to Ennis could see several inches of snow.
All forecast models show widespread areas of snow across SW Montana Saturday night through Monday. Regardless of who gets more or less, there will be enough snow and wind to produce difficult to hazardous travel conditions at all levels Sunday into Monday.