Weather WorldUpper Lake, MT Weather Forecast
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| TONIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | WEDNESDAY NIGHT | THURSDAY |
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| Partly Cloudy | Mostly Sunny | Partly Cloudy | Sunny | Clear | Mostly Sunny | Mostly Clear | Mostly Sunny | Partly Cloudy | Partly Cloudy | Partly Cloudy | Partly Cloudy |
| Lo: 46°FLo: 8°C | Hi: 76°FHi: 24°C | Lo: 46°FLo: 8°C | Hi: 76°FHi: 24°C | Lo: 46°FLo: 8°C | Hi: 80°FHi: 27°C | Lo: 46°FLo: 8°C | Hi: 76°FHi: 24°C | Lo: 46°FLo: 8°C | Hi: 75°FHi: 24°C | Lo: 46°FLo: 8°C | Hi: 76°FHi: 24°C |
POP = Probability of Precipitation.
Weather Outlook Updated: 1222 PM MDT Fri Sep 18 2026 
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Issued: 1228 PM MDT Fri Sep 18 2026
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KEY MESSAGES:- Thunderstorms this afternoon/evening with locally heavy rain, minor runoff concerns near burn scars and susceptible terrain.
- Steady precipitation tonight into Saturday south of I-90.
- Warming and drying trend Sunday into the first part of next week.
This afternoon through Saturday afternoon: Broad-scale lift and partial clearing north of an upper low over southwest Idaho will trigger rounds of showers and thunderstorms this afternoon and evening, primarily from I-90 sout...