Northwest Montana

Issued: 07/07/2026 6:55 p.m. MDT

Tonight...Increasing clouds with areas of smoke haze. Isolated showers and thunderstorms developing towards morning west of the Cabinet Mountains. Very mild with lows in the 50s except upper 60s in thermal belts on slopes and hillsides with near 60 around 5000 feet. Light wind except local south to southwest wind 10 to 15 mph along portions of Lake Koocanusa. Ridge top winds southwest 10 to 20 mph.

Wednesday…Variable cloudiness in the morning with isolated to scattered showers and thunderstorms then becoming mostly sunny and breezy in the afternoon. Areas of smoke haze. Highs in the mid 80s to mid 90s with near 70 around 5000 feet. Afternoon south to southwest wind 15 to 25 mph with gusts to 30 mph through favored canyons and along portions of Lake Koocanusa. Ridge top winds west to southwest 15 to 30 mph with gusts to 40 mph.

Wednesday night…Increasing high cloudiness with areas of smoke haze. Lows in the upper 40s to upper 50s except lower 60s in thermal belts on slopes and hillsides with mid 50s around 5000 feet. Evening west to southwest wind 10 to 20 mph with gusts to 30 mph through favored canyons and along portions of Lake Koocanusa decreasing overnight. Ridge top winds west 15 to 30 mph with gusts to 40 mph.

Thursday...Considerable high cloudiness in the morning then becoming mostly sunny in the afternoon and a little cooler. Highs in the 80s with upper 60s around 5000 feet. West to southwest wind 10 to 20 mph with gusts to 30 mph through favored canyons, along portions of Lake Koocanusa and across ridge tops.

Extended Outlook(Friday through Tuesday):

Friday through Tuesday...Dry and unseasonably warm. Lows in the mid 40s to mid 50s Friday and Saturday warming to the 50s Sunday through Tuesday with thermal belts on slopes and hillsides warming to the upper 60s to near 70 by Sunday through Tuesday. Highs in the mid 80s to lower 90s Friday and Saturday warming to the upper 80s to upper 90s by Monday and Tuesday. Around 5000 feet lows in the mid 50s Friday and Saturday warming to the lower 60s by Sunday through Tuesday. Highs in the lower 70s Friday through Sunday warming to the mid 70s by Monday and Tuesday.

In-Depth Weather Discussion for Northwest Montana/North Idaho/Northern Rockies 

Issued 07/04/2026 8:00 p.m. MDT / 7:00 p.m. PDT

SHORT TERM (SATURDAY NIGHT THROUGH MONDAY):       

      Fairly quiet conditions for the short-term portion of the forecast. A passing shortwave to the north of our region along with surface pressure falls across Montana has resulted in elevated afternoon west to southwest winds across our region but these will largely be decreasing by sunset and should make for a wonderful evening for everyone that will be out enjoying Independence Day celebrations. Warm conditions will return for Sunday with slightly less breezy conditions but the atmosphere will remain stable. By Monday a surface high is projected to slide southeast along the front range of the Northern Rockies into southern Alberta/northern Montana. This will create a tightening surface gradient as a thermal trough begins to deepen in the Columbia Basin of Washington so expect some increase of northeast winds after midnight on Sunday into Monday morning in the areas that are exposed to these winds (ie: portions of Lake Koocanusa, Noxon, Sandpoint and the Purcell Trench from Sandpoint south) as well as across ridge tops. Where these winds surface temperatures will remain very much elevated and uncomfortable for sleeping as the atmosphere will be further drying and warming. Winds won't be too strong but could see some gusts around 20 to 25 mph in the late night/early morning hours of Monday especially along portions of Lake Koocanusa and in those favored canyons across Northwest Montana. Temperatures will remain around 5 to 10 degrees above early July seasonal averages.   

LONG TERM (TUESDAY NIGHT THROUGH SUNDAY): 

     Will be watching a weak upper level low that is currently spinning off the Southern California coastline as of this writing on Saturday evening. This feature is anticipated to begin moving northwest parallel to the California coastline before moving inland across Central Oregon during the day on Monday. Instability will be increasing with thunderstorms anticipated to break out across much of Central and Northeast Oregon. As this feature moves northeast Monday night into early Tuesday morning we could see some elevated, forced convection break out across the Northern Rockies although at this time it looks more likely that the upper level low and it's associated instability and jet dynamics may remain too far south to bring us much more than perhaps a few clouds. Still with as dry as conditions are have included mention of a slight chance of showers/thunder for Monday night into Tuesday morning to bring attention to this possibility. By Wednesday an approaching shortwave will pass by the region knocking temperatures back down close to seasonal averages, increasing winds and possibly bringing a few showers mainly to North Idaho and more likely across Boundary County. This will not be a big rain maker but any rainfall we can get at this point would be very beneficial given how dry May and June were across the Northern Rockies and all areas with the exception of the Eureka and Rexford areas were well below their normal May and June rainfalls. Wednesday also is looking rather breezy if not windy as gusty winds will accompany the airmass change as surface pressures rise in the cooler air west of the Cascades and surface pressures fall east across Montana where hot weather will be more prevalent. Some uncertainty in the end of this forecast period. All models show a strengthening continental ridge setting up across the Intermountain West which is typical for this time of year. The uncertainty lies in how much this ridge will amplify and where it's axis will set up. This is also due in part to an equally strong Gulf of Alaska upper level low that will also be amplifying offshore. If the ridge axis lines up more north/south then our region can anticipate a major warm up with hot conditions developing with 90s becoming widespread across valley locations with our typical hot spots in Northwest Montana likely seeing 100 degrees or hotter. If the ridge axis remains more positively tilted and anchored across eastern Montana and the Dakotas then our temperatures will be close to seasonal averages in the 80s but with breezy to possibly windy conditions each day. Overall conditions do look to remain dry through the period although if the more north/south ridge axis does indeed occur then it is also likely that we will need to watch for shortwaves rotating around the ridge along with any vort maxes as these would bring increased threats of mainly elevated, forced convection across our region. Stay tuned!