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Halfmoon Lake Weather Forecast
| TONIGHT | THURSDAY | THURSDAY NIGHT | FRIDAY | FRIDAY NIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | MONDAY NIGHT | TUESDAY |
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| Patchy Fog | Mostly Sunny | Chance of Rain | Chance of Rain | Partly Cloudy | Chance of T-Storm | Mostly Clear | Mostly Sunny | Mostly Clear | Mostly Sunny | Mostly Clear | Partly Cloudy |
| Lo: 45°FLo: 7°C | Hi: 70°FHi: 21°C | Lo: 46°FLo: 8°C | Hi: 66°FHi: 19°C | Lo: 46°FLo: 8°C | Hi: 65°FHi: 18°C | Lo: 46°FLo: 8°C | Hi: 66°FHi: 19°C | Lo: 46°FLo: 8°C | Hi: 66°FHi: 19°C | Lo: 46°FLo: 8°C | Hi: 65°FHi: 18°C |
| POP: 20% | POP: 30% | POP: 20% |
POP = Probability of Precipitation.
Weather Outlook Updated: 1223 PM MDT Wed Sep 16 2026 
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Issued: 1133 AM MDT Wed Sep 16 2026
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KEY MESSAGES:- Warm and dry today with sunny skies; breezy easterly winds developing this evening.
- Showers and thunderstorms Thursday into Friday, generally south of Highway 12 and I-90. Storms will be capable of brief heavy rain, small hail, and sudden wind gusts up to 45 mph.
- Another warming and drying trend Sunday through early next week.
A brief area of high pressure over the region today will bring pleasant, sunny, and near-normal temperatures, with highs reaching the 70s in west...