Weather WorldCastle Lake, MT Weather Forecast
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Castle Lake Weather Forecast
| TONIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | WEDNESDAY NIGHT | THURSDAY | THURSDAY NIGHT | FRIDAY |
 |  |  |  |  | |  | | | | |  |
| Thunderstorms | Chance of T-Storm | Mostly Clear | Sunny | Partly Cloudy | Chance of T-Storm | Chance of T-Storm | Chance of T-Storm | Partly Cloudy | Mostly Sunny | Partly Cloudy | Rain Showers |
| Lo: 39°FLo: 4°C | Hi: 61°FHi: 16°C | Lo: 31°FLo: -1°C | Hi: 70°FHi: 21°C | Lo: 39°FLo: 4°C | Hi: 71°FHi: 22°C | Lo: 39°FLo: 4°C | Hi: 69°FHi: 21°C | Lo: 35°FLo: 2°C | Hi: 69°FHi: 21°C | Lo: 35°FLo: 2°C | Hi: 70°FHi: 21°C |
| POP: 90% | POP: 90% | POP: 40% | POP: 40% | POP: 40% | POP: 20% |
POP = Probability of Precipitation.
Weather Outlook Updated: 614 PM MDT Sat Aug 29 2026 
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Issued: 1255 PM MDT Sat Aug 29 2026
Key Messages
- Scattered showers and thunderstorms through Sunday.
- West winds gusting 25-40 mph Sunday afternoon-evening.
- Below normal temperatures Sunday(70s) warming into the 80s-lower 90s by mid-week.
- Chances for showers and thunderstorms increase late week.
Discussion
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Rest of Today through Friday...
Unsettled pattern over the next 36 hours as a Fall like upper system approaches from the west and slides just to the north of the area Sunday into Monday. This close approach will keep a chance of s...