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Potomac, IL Weather Forecast
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Potomac Weather Forecast
| REST OF TONIGHT | FRIDAY | FRIDAY NIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | MONDAY | TUESDAY | WEDNESDAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT |
 |  |  | |  | | | | | |  | |
| Mostly Clear | Sunny | Chance of T-Storm | Sunny | Partly Cloudy | Mostly Clear | Mostly Clear | Mostly Clear | Mostly Clear | Partly Cloudy | Partly Cloudy | Mostly Clear |
| Lo: 71°FLo: 22°C | Hi: 95°FHi: 35°C | Lo: 71°FLo: 22°C | Hi: 91°FHi: 33°C | Lo: 65°FLo: 18°C | Hi: 85°FHi: 29°C Lo: 60°FLo: 16°C | Hi: 85°FHi: 29°C Lo: 60°FLo: 16°C | Hi: 85°FHi: 29°C Lo: 60°FLo: 16°C | Hi: 85°FHi: 29°C Lo: 60°FLo: 16°C | Hi: 90°FHi: 32°C Lo: 61°FLo: 16°C | Hi: 90°FHi: 32°C Lo: 61°FLo: 16°C | Lo: 71°FLo: 22°C |
| POP: 30% |
POP = Probability of Precipitation.
Weather Outlook Updated: 1037 PM CDT Thu Sep 03 2026 
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Issued: 627 PM CDT Thu Sep 3 2026
Key Messages
- An Extreme Heat Warning remains in effect areawide through Friday and for parts of the area Saturday with dangerous heat index values between 100 and 109 degrees.
- There is a very low chance (10-15%) for an isolated severe thunderstorm late this afternoon and evening and again Friday afternoon and evening. The primary threat will be damaging wind gusts. A marginal severe risk lingers over portions of east central Illinois Saturday.
Discussion
... Issued at 142 PM CDT Thu Sep 3 2026
Exces...