Sep 23, 2013 4:43 PM by Meteorologist Mike Heard
Fall officially began Sunday, however, our first good winter type storm event will impact Montana beginning Tuesday night.
A digging trough of Low pressure will usher in much colder air and moisture into the Northern Rockies Tuesday through Friday of this week and that means snow levels will start out very high Tuesday (above 7,000') but will fall quickly into Wednesday and Thursday down to valley floors but accumulations likely to stay above 5,000' for much of western and southwestern Montana.
Moderate to heavy rain will hit the lower elevations with .50" to 1.50" likely and possibly more in a few localized areas by the end of the week.
Winter Storm Watch has been issued for ALL of SW Montana beginning Wednesday morning through Thursday afternoon.
Timing: Rain changing to snow will begin Wednesday morning with heaviest snowfall likely above 5,000'.
Snow accumulations: 16"-24" of snow is possible above 7,000' and 5,000'-7,000' foot levels 6"-14" of snow is possible.
Winds & Visibilities: Northerly winds will be gusty at times and may reduce visibilities with blowing snow.
Locations affected: Battle Ridge pass, Targhee pass, West Yellowstone, Boulder Hill, Elk Park pass, Homestake pass, Big Hole pass, Chief Joseph pass, Monida pass, Kings Hill pass, Raynolds pass, Lost Trail pass, MacDonald pass, Lolo pass.
Winter Storm Watch means there is potential for significant snow accumulations that may impact travel. Continue to monitor the latest forecast.
Chief Meteorologist Mike Heard warned us last week of a powerful storm to arrive this week and forecast models are still in line with that forecast. Updates on this storm are coming up at 5:30pm and 10pm on KXLF and KBZK.