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Fall River County Weather Forecast
| TODAY | TONIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | WEDNESDAY NIGHT |
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| Patchy Fog | Chance of T-Storm | Chance of T-Storm | Chance of T-Storm | Chance of T-Storm | Chance of T-Storm | Chance of Showers | Chance of Showers | Chance of Showers | Chance of T-Storm | Clearing | Mostly Clear |
| Hi: 79°FHi: 26°C | Lo: 55°FLo: 13°C | Hi: 70°FHi: 21°C | Lo: 51°FLo: 11°C | Hi: 65°FHi: 18°C | Lo: 49°FLo: 9°C | Hi: 69°FHi: 21°C | Lo: 50°FLo: 10°C | Hi: 75°FHi: 24°C | Lo: 51°FLo: 11°C | Hi: 79°FHi: 26°C | Lo: 51°FLo: 11°C |
| POP: 70% | POP: 70% | POP: 90% | POP: 20% | POP: 20% | POP: 20% | POP: 40% | POP: 20% |
POP = Probability of Precipitation.
Weather Outlook Updated: 647 AM MDT Fri Sep 18 2026 
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Issued: 524 AM MDT Fri Sep 18 2026
Key Messages
- Cooler and wet conditions will persist through the weekend.
- Gradual warmup early next week.
Discussion
...(This Evening Through Thursday) Issued at 110 PM MDT Thu Sep 17 2026
Water Vapor and upper air models show southwest flow aloft, as ridging sits over the northern and central plains. Upper low currently sits over the west coast, while a shortwave currently sits over WY riding the southwest flow into the Dakotas. 18Z surface analysis shows associated surface low over the CO/WY border...