Weather WorldJefferson County, IL Weather Forecast
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Jefferson County Weather Forecast
| OVERNIGHT | THURSDAY | THURSDAY NIGHT | FRIDAY | FRIDAY NIGHT | SATURDAY | SUNDAY | SUNDAY NIGHT | MONDAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT |
 | |  |  |  |  | | | | | | |
| Patchy Fog | Patchy Fog | Partly Cloudy | Clearing | Mostly Clear | Mostly Clear | Mostly Clear | Clear | Sunny | Clear | Mostly Clear | Mostly Clear |
| Lo: 49°FLo: 9°C | Hi: 65°FHi: 18°C | Lo: 41°FLo: 5°C | Hi: 55°FHi: 13°C | Lo: 31°FLo: -1°C | Hi: 59°FHi: 15°C Lo: 31°FLo: -1°C | Hi: 59°FHi: 15°C Lo: 31°FLo: -1°C | Lo: 35°FLo: 2°C | Hi: 65°FHi: 18°C | Lo: 39°FLo: 4°C | Hi: 65°FHi: 18°C Lo: 39°FLo: 4°C | Hi: 65°FHi: 18°C Lo: 39°FLo: 4°C |
POP = Probability of Precipitation.
Weather Outlook Updated: 142 AM CST Thu Nov 05 2026 
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Issued: 1259 AM CST Thu Nov 5 2026
Key Messages
- Another mild day is in store today with highs in the mid to upper 60s and sunny skies.
- A cold front will pass through Thursday night and Friday morning bringing some of the coolest temperatures we have seen yet this Fall. Highs in the 50s are forecast this weekend with lows in the low to mid 30s.
- Dry conditions will persist for the next several days with a warm-up into the 60s expected to begin Monday and continuing through midweek.
Discussion
... Issued at 1258 PM CST Wed Nov 4 2026
Pa...