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| REST OF TONIGHT | WEDNESDAY | WEDNESDAY NIGHT | THURSDAY | THURSDAY NIGHT | FRIDAY | FRIDAY NIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | MONDAY | MONDAY NIGHT |
 |  |  |  |  | | |  | | | | |
| Chance of T-Storm | Chance of T-Storm | Chance of Showers | Mostly Sunny | Clear | Sunny | Mostly Clear | Chance of Showers | Chance of Showers | Chance of Showers | Chance of Showers | Chance of T-Storm |
| Lo: 71°FLo: 22°C | Hi: 81°FHi: 27°C | Lo: 65°FLo: 18°C | Hi: 81°FHi: 27°C | Lo: 55°FLo: 13°C | Hi: 85°FHi: 29°C | Lo: 65°FLo: 18°C | Hi: 85°FHi: 29°C | Lo: 61°FLo: 16°C | Hi: 81°FHi: 27°C Lo: 61°FLo: 16°C | Hi: 81°FHi: 27°C Lo: 61°FLo: 16°C | Lo: 65°FLo: 18°C |
| POP: 50% | POP: 70% | POP: 40% | POP: 50% | POP: 50% | POP: 40% | POP: 40% | POP: 60% |
POP = Probability of Precipitation.
Weather Outlook Updated: 1239 AM CDT Wed Sep 09 2026 
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Issued: 1219 AM CDT Wed Sep 9 2026
Key Messages
- Heat indices will top out around 100 degrees Wednesday afternoon south of I-72 due to high temperatures in the 90s and rising humidity levels.
- Scattered thunderstorms are forecast Wednesday afternoon, becoming more widespread Wednesday night along a stalled front; localized heavy rainfall of 1 to 3 inches could cause localized flooding, particularly south of I-70. There is a marginal risk (level 1 of 5) for severe thunderstorms for much of central and southeast Illinois.
Discussion
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