Weather WorldWestby, MT Weather Forecast
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Westby Weather Forecast
| TONIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | WEDNESDAY NIGHT | THURSDAY | FRIDAY | SATURDAY |
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| Partly Cloudy | Sunny | Showers | Chance of T-Storm | Chance of Showers | Mostly Sunny | Chance of Showers | Chance of Showers | Mostly Clear | Mostly Clear | Mostly Clear | Mostly Clear |
| Lo: 39°FLo: 4°C | Hi: 69°FHi: 21°C | Lo: 50°FLo: 10°C | Hi: 61°FHi: 16°C | Lo: 41°FLo: 5°C | Hi: 65°FHi: 18°C | Hi: 69°FHi: 21°C Lo: 45°FLo: 7°C | Hi: 69°FHi: 21°C Lo: 45°FLo: 7°C | Hi: 75°FHi: 24°C Lo: 45°FLo: 7°C | Hi: 75°FHi: 24°C Lo: 45°FLo: 7°C | Hi: 75°FHi: 24°C Lo: 45°FLo: 7°C | Hi: 75°FHi: 24°C Lo: 45°FLo: 7°C |
| POP: 80% | POP: 90% | POP: 30% |
POP = Probability of Precipitation.
Weather Outlook Updated: 641 PM MDT Sat Sep 12 2026 
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Issued: 211 PM MDT Sat Sep 12 2026
Key Messages
- Rain will be likely across northeast portions of Montana Sunday afternoon through Monday morning. Precipitation totals will range between 0.01" and 0.25".
- A Lake Wind Advisory has been issued due to wind speeds being expected to reach 20 to 25 mph sustained Sunday afternoon. Wave heights have the potential to reach 3 ft.
- Winds will likely reach Lake Wind Advisory criteria again Monday afternoon. Wave heights have the potential to reach 4.5 ft.
Discussion
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Zonal westerly flow aloft so...