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Upper Flat Lake, IL Weather Forecast
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Upper Flat Lake Weather Forecast
| TONIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | VETERANS DAY | WEDNESDAY NIGHT | THURSDAY |
 |  |  | | | | | | |  | | |
| Partly Cloudy | Mostly Sunny | Mostly Clear | Sunny | Mostly Clear | Sunny | Clear | Clear | Partly Cloudy | Partly Cloudy | Partly Cloudy | Partly Cloudy |
| Lo: 29°FLo: -2°C | Hi: 55°FHi: 13°C | Lo: 31°FLo: -1°C | Hi: 61°FHi: 16°C | Lo: 35°FLo: 2°C | Hi: 69°FHi: 21°C | Hi: 69°FHi: 21°C Lo: 41°FLo: 5°C | Hi: 69°FHi: 21°C Lo: 41°FLo: 5°C | Lo: 39°FLo: 4°C | Hi: 61°FHi: 16°C Lo: 35°FLo: 2°C | Hi: 61°FHi: 16°C Lo: 35°FLo: 2°C | Hi: 59°FHi: 15°C Lo: 31°FLo: -1°C |
POP = Probability of Precipitation.
Weather Outlook Updated: 728 PM CST Fri Nov 06 2026 
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Issued: 527 PM CST Fri Nov 6 2026
Key Messages
- A Freeze Warning remains in effect area-wide tonight into Saturday morning.
- Hazardous weather is not anticipated through next Friday as dry conditions prevail and temperatures gradually warm to start the week.
Aviation
/00Z TAFS THROUGH 06Z SUNDAY/... Issued at 517 PM CST Fri Nov 6 2026
MVFR stratus continues to push south and erode as dry air filters in from the north. VFR conditions with light and variable winds will prevail after the deck exits. The exception to this will be in river...