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Foster Lake Weather Forecast
| THIS AFTERNOON | TONIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | SUNDAY NIGHT | COLUMBUS DAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | WEDNESDAY NIGHT |
 |  |  |  | | | | |  |  |  | |
| Sunny | Mostly Clear | Mostly Cloudy | Mostly Cloudy | Sunny | Mostly Clear | Mostly Clear | Mostly Clear | Chance of T-Storm | Chance of T-Storm | Chance of Showers | Chance of T-Storm |
| Hi: 89°FHi: 32°C | Lo: 59°FLo: 15°C | Hi: 81°FHi: 27°C | Lo: 59°FLo: 15°C | Hi: 81°FHi: 27°C | Hi: 91°FHi: 33°C Lo: 59°FLo: 15°C | Hi: 91°FHi: 33°C Lo: 59°FLo: 15°C | Lo: 65°FLo: 18°C | Hi: 89°FHi: 32°C | Lo: 60°FLo: 16°C | Hi: 81°FHi: 27°C | Hi: 80°FHi: 27°C Lo: 61°FLo: 16°C |
| POP: 20% | POP: 20% | POP: 50% | POP: 50% |
POP = Probability of Precipitation.
Weather Outlook Updated: 1138 AM CDT Fri Oct 09 2026 
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Issued: 1204 PM CDT Fri Oct 9 2026
Key Messages
- Near-record temperatures are forecast this afternoon and Monday.
- The remnants of Tropical Cyclone Isaias will bring slightly "cooler" temperatures over the weekend due to clouds, as well as chances of light rain in southeast Missouri and southwest Illinois on Saturday and Saturday night.
Aviation
/18Z TAFS THROUGH 00Z SUNDAY/... Issued at 1203 PM CDT Fri Oct 9 2026
Dry/VFR conditions with a mostly clear sky are forecast through this evening. Increasing high-level clouds are expected ove...