Weather WorldBig Flat Lake, IL Weather Forecast
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Big Flat Lake Weather Forecast
| TONIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | WEDNESDAY NIGHT | THURSDAY | THURSDAY NIGHT | FRIDAY |
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| Chance of Rain | Chance of Rain | Patchy Fog | Cloudy | Mostly Cloudy | Showers Likely | Chance of T-Storm | Chance of T-Storm | Chance of T-Storm | Chance of Showers | Chance of Showers | Mostly Cloudy |
| Lo: 59°FLo: 15°C | Hi: 65°FHi: 18°C | Lo: 51°FLo: 11°C | Hi: 70°FHi: 21°C | Lo: 60°FLo: 16°C | Hi: 75°FHi: 24°C | Lo: 55°FLo: 13°C | Hi: 69°FHi: 21°C | Lo: 49°FLo: 9°C | Hi: 69°FHi: 21°C Lo: 45°FLo: 7°C | Hi: 69°FHi: 21°C Lo: 45°FLo: 7°C | Hi: 65°FHi: 18°C Lo: 41°FLo: 5°C |
| POP: 50% | POP: 50% | POP: 70% | POP: 70% | POP: 50% | POP: 20% | POP: 20% | POP: 20% |
POP = Probability of Precipitation.
Weather Outlook Updated: 809 PM CDT Sat Oct 31 2026 
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Issued: 656 PM CDT Sat Oct 31 2026
Key Messages
- Intermittent sprinkles/light rain showers are expected this evening with temperatures in the 60s.
- Another system will affect the region Monday night through Wednesday with intermittent rain and a few thunderstorms. Widespread beneficial rainfall is expected with this system. Hazardous weather is not expected at this time.
- Temperatures cool gradually through the end of the week, though highs are expected to remain near to above normal for early November.
Aviation
/00Z TAFS THROUGH 06Z M...