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Longcommon Park, IL Weather Forecast
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Longcommon Park Weather Forecast
| LATE THIS AFTERNOON | TONIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | WEDNESDAY NIGHT |
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| Chance of Showers | Chance of T-Storm | Chance of T-Storm | Thunderstorms | Chance of T-Storm | Chance of Showers | Chance of Showers | Chance of Showers | Mostly Cloudy | Mostly Cloudy | Mostly Cloudy | Mostly Cloudy |
| Hi: 70°FHi: 21°C | Lo: 61°FLo: 16°C | Hi: 79°FHi: 26°C | Lo: 65°FLo: 18°C | Hi: 69°FHi: 21°C | Lo: 59°FLo: 15°C | Hi: 65°FHi: 18°C | Lo: 55°FLo: 13°C | Hi: 65°FHi: 18°C | Lo: 55°FLo: 13°C | Hi: 65°FHi: 18°C | Lo: 55°FLo: 13°C |
| POP: 50% | POP: 50% | POP: 90% | POP: 80% | POP: 70% | POP: 50% | POP: 50% | POP: 20% |
POP = Probability of Precipitation.
Weather Outlook Updated: 251 PM CDT Fri Sep 18 2026 
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Issued: 257 PM CDT Fri Sep 18 2026
Key Messages
- Periods of heavy rain and scattered thunderstorms late tonight through Sunday night. Localized flash flooding will be possible where the heaviest rains occur over the same areas. A Flood Watch for flash flooding is in effect for much of northern Illinois and far northwest Indiana late tonight through Saturday morning.
- Below normal temps early next week then dry weather expected mid/late next week.
Discussion
... Issued at 257 PM CDT Fri Sep 18 2026
An unseasonably strong mid-level ridge...