Northwest Montana Regional Forecast
Includes Lincoln and Sanders Counties ( Libby, Troy, Eureka, Yaak, Bull Lake, Noxon, Heron, Trout Creek, Thompson Falls, and The Cabinet Mountains)
Issued Saturday March 23, 2019 - 5:50 p.m.
Saturday night…Partly cloudy then increasing clouds after midnight. Lows in the upper 20s to mid 30s with near 30 around 5000 feet. Light wind with ridge top winds southeast 5 to 15 mph.
Sunday…Mostly cloudy with scattered rain and snow showers. Snow level near 5000 feet. Local snow accumulations of up to 1 inch possible above 5000 feet. Highs in the 50s to near 60 with mid 30s around 5000 feet. Light east wind with ridge top winds east 5 to 15 mph.
Sunday night…Mostly cloudy with scattered rain and snow showers. Snow level near 4000 feet. Local snow accumulations of up to 1 inch possible above 4500 feet. Lows in the upper 20s to mid 30s with upper 20s around 5000 feet. Light wind with ridge top winds south 5 to 15 mph.
Monday…Variable cloudiness. A slight chance of mountain snow showers. Snow level near 4500 to 5000 feet. Highs in the lower 50s to near 60 with near 40 around 5000 feet. Light southwest wind.
Extended Outlook (Tuesday through Saturday)
Tuesday and Wednesday…Unsettled with a chance of rain and snow showers at night in the valleys with a chance of rain showers during the day. A chance of snow showers in the higher elevations. Lows in the mid 20s to lower 30s with mid 20s around 5000 feet. Highs in the mid 40s to mid 50s with lower 30s around 5000 feet.
Thursday…Cooler with a chance of rain and snow showers in the valleys and a chance of snow showers in the higher elevations. Lows in the 20s with mid 20s around 5000 feet. Highs in the lower 40s to lower 50s with near 30 around 5000 feet.
Friday and Saturday…A slight chance of rain and snow showers in the valleys and snow showers in the higher terrain. Lows in the upper teens to mid 20s with near 20 around 5000 feet. Highs in the lower 40s to lower 50s with near 30 around 5000 feet.
In-Depth Weather Discussion for Northwest Montana/Rockies
Issued 03/23/2019 6:05 p.m.
Yet another day of above average temperatures for late March with most valley locations across Lincoln and Sanders Counties rising into the upper 50s to lower 60s. These temperatures are anywhere from 5 to 10 degrees above the normal for March 23. Forecasting at the end of this week has been challenging at best with several busts concerning temperatures and sky conditions. It does appear that cloud cover will increase overnight tonight which should help to hold temperatures up with mainly the colder valleys and those valleys near the British Columbia border dropping down to freezing or below while higher terrain begins to cool off as well as the atmosphere undergoes cooling as well. Sunday will see the next shortwave rotate up into the region from the south and southwest with more cloud cover and scattered showers with snow levels running near 5000 feet. It will likely be cooler with the added cloud cover helping to limit incoming solar heating. Showers will gradually taper off Sunday night from south to north as that shortwave lifts northward into Canada. Some patchy valley fog will be possible Monday morning across any valleys that clear out in time overnight. Shortwave upper level ridge will build in for Monday providing generally dry and stable conditions with the next shortwave beginning to approach from the west late in the day. From Tuesday through the rest of the week look for generally unsettled conditions with at least chances for showers each day with some days having better odds than others. Cooler conditions are also becoming increasingly likely though just how cool is still not well resolved amongst models. Colder models would imply good chances for accumulating valley snowfall whereas warmer models would keep snow levels above most valley floors with the exceptions being McGinnis Meadows and perhaps Yaak and Trego. With so much uncertainty have simply labeled the extended portion of the outlook with chances of valley rain or snow and snow in the higher elevations. Cooler conditions along with mountain snowfall look to have higher confidence. The main challenges revolve around how a west coast upper level trough will phase with the western portion of the Hudson Bay low which looks to re-intensify once again next week and send more very cold air southward into the United States. This is supported by a strong closed upper level ridge over far Northwest British Columbia and Southeast Alaska. Needless to say this appears to be a rather complex pattern so keep checking back for the latest updates.