Mar 16, 2013 1:22 AM by Meteorologist Mike Rawlins
UPDATED - 8:59PM FRIDAY
New model guidance suggests Sunday's winter storm will still bring heavy snow for parts of the Treasure State, but less for others.
Using the NAM model, I'm coming up with a general 0.5-1.5" snowfall for the lower elevations of north central Montana.
I still expect as much as 6-12" in the mountainous areas, so traveling the passes will be slow and treacherous.
We'll continue analyzing new data and will post updates as needed.
We got spoiled this week with unseasonably warm temperatures, but the St. Patrick's Day weekend will be quite different.
A cold front will continue pushing south across central Montana through the evening hours.
Overnight, temperatures will drop into the 20s/30s with areas of dense fog along and north of Highway 2.
Sunday's winter storm is still sitting off the Pacific Coast right now, but will arrive in Big Sky Country by Sunday morning.
As the surface low and cold front approach Saturday night, snow will start developing in the mountains of western Montana.
Most of the snow with this system will fall in the mountains, but I'm still expecting a couple inches of accumulation at lower elevations.
The ECMWF model has a pretty good handle on snowfall amounts for this event and is the preferred model at this time.
Right now, our forecast continues to call for 1-3" at lower elevations and in valleys, with 6-11" in the mountains.
Strong winds will also develop as the surface low moves southeast across the state.
Gusts up to 40 mph will be possible on Sunday across the plains of central and north central Montana.
Travelers should expect deteriorating driving conditions Saturday night and into Sunday.
Roads will become icy and snow-covered as temperatures drop below freezing and the snow starts to accumulate.
This system will also stress young livestock due to freezing temperatures, snow and gusty winds.
There is also the potential for some freezing rain and heavier snow to fall in northeast Montana.
A Winter Storm Watch has been issued and folks living on the Hi-Line should keep a close eye on the forecast.
Sunday's high temperatures will struggle to get out of the 20s up north, with areas farther south reaching into the 30s.
Stay with STORMTracker Weather for continuous coverage of this winter storm.