Weather WorldO'Fallon, IL 7-Day Weather Forecast
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O'Fallon Weather Forecast
O'Fallon, IL Weather Forecast Date: 454 PM CST Tue Nov 03 2026
Weather forecast for O'Fallon, IL
Tonight Lo: 51°F Lo: 11°C |
Tonight... Rain with a slight chance of thunderstorms this evening, then a chance of rain after midnight. Cooler with lows in the lower 50s. South winds 10 to 15 mph with gusts up to 30 mph. Chance of rain near 100%. |
Wed Hi: 61°FHi: 16°C Lo: 41°F Lo: 5°C |
Wednesday... Mostly cloudy. Cooler with highs in the lower 60s. West winds 10 to 15 mph. |
Thu Hi: 65°FHi: 18°C Lo: 45°F Lo: 7°C |
Thursday... Sunny. Highs in the mid 60s. West winds 5 to 10 mph. |
| Fri Hi: 59°FHi: 15°C Lo: 39°F Lo: 4°C |
Friday... Mostly cloudy in the morning, then becoming partly sunny. Highs in the upper 50s. |
| Sat Hi: 55°FHi: 13°C Lo: 35°F Lo: 2°C |
Saturday... Partly sunny. Highs in the mid 50s. |
| Sun Hi: 65°FHi: 18°C Lo: 35°F Lo: 2°C |
Sunday... Mostly clear. Highs in the mid 60s. Lows in the mid 30s. |
| Mon Hi: 65°FHi: 18°C Lo: 35°F Lo: 2°C |
Monday... Mostly clear. Highs in the mid 60s. Lows in the mid 30s. |
| Mon Hi: 65°FHi: 18°C Lo: 41°F Lo: 5°C |
Monday... Mostly clear. Highs in the mid 60s. Lows in the mid 30s. |
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