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Keystone Weather Forecast
| TODAY | TONIGHT | LABOR DAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | WEDNESDAY NIGHT | THURSDAY | THURSDAY NIGHT | FRIDAY | FRIDAY NIGHT |
 |  |  |  |  | | | | | | | |
| Chance of T-Storm | Chance of T-Storm | Clearing | Mostly Clear | Sunny | Clear | Mostly Sunny | Mostly Clear | Mostly Sunny | Clear | Sunny | Mostly Clear |
| Hi: 89°FHi: 32°C | Lo: 61°FLo: 16°C | Hi: 81°FHi: 27°C | Lo: 55°FLo: 13°C | Hi: 75°FHi: 24°C | Lo: 49°FLo: 9°C | Hi: 75°FHi: 24°C | Lo: 51°FLo: 11°C | Hi: 81°FHi: 27°C | Lo: 55°FLo: 13°C | Hi: 79°FHi: 26°C | Lo: 51°FLo: 11°C |
| POP: 20% | POP: 50% |
POP = Probability of Precipitation.
Weather Outlook Updated: 622 AM MDT Sun Sep 06 2026 
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Issued: 529 AM MDT Sun Sep 6 2026
Key Messages
- Above average temperatures remain in the forecast. The hottest day will be today with highs in the mid to upper 90s with 80s and 90s expected Sunday and Monday.
- Elevated fire weather conditions are expected through the weekend.
- Isolated to scattered thunderstorms are expected through Sunday, focusing on this evening and Sunday afternoon/evening
Discussion
...(This Afternoon Through Friday) Issued at 1139 AM MDT Sat Sep 5 2026
For the rest of today, isolated storms are drifting northward...