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Flat Lake Weather Forecast
| THIS AFTERNOON | TONIGHT | THURSDAY | THURSDAY NIGHT | FRIDAY | FRIDAY NIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | MONDAY NIGHT |
 |  | | |  |  | |  |  |  | | |
| Sunny | Clearing | Mostly Sunny | Partly Cloudy | Chance of Rain | Windy | Chance of Rain | Mostly Cloudy | Chance of Rain | Chance of Rain | Chance of Rain | Chance of Rain |
| Hi: 65°FHi: 18°C | Lo: 41°FLo: 5°C | Hi: 79°FHi: 26°C | Lo: 59°FLo: 15°C | Hi: 75°FHi: 24°C | Lo: 55°FLo: 13°C | Hi: 61°FHi: 16°C | Lo: 39°FLo: 4°C | Hi: 49°FHi: 9°C | Hi: 45°FHi: 7°C Lo: 35°FLo: 2°C | Hi: 45°FHi: 7°C Lo: 35°FLo: 2°C | Lo: 31°FLo: -1°C |
| POP: 20% | POP: 40% | POP: 20% | POP: 40% | POP: 40% | POP: 20% |
POP = Probability of Precipitation.
Weather Outlook Updated: 221 PM CDT Wed Oct 21 2026 
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Issued: 239 PM CDT Wed Oct 21 2026
Key Messages
- Thursday and Friday, highs will reach the upper 70s to low 80s. These temperatures are 20-25 degrees above normal, and will approach record highs.
- Rain chances return Friday with a 20-40% chance of light showers over northeastern SD and western MN. Additional chances for showers come Saturday along a cold front, where there is a 10-40% chance to see a tenth of an inch of rain over northeastern SD and western MN.
- Southerly winds increase Friday, with widespread 30-40 mile per hour gus...