Weather WorldGrant Park Decatur, IL 7-Day Weather Forecast
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Grant Park Decatur Weather Forecast
Grant Park Decatur, IL Weather Forecast Date: 1237 AM CDT Mon Aug 24 2026
Weather forecast for Grant Park Decatur, IL
Tonight Lo: 55°F Lo: 13°C |
Tonight... Mostly clear. Patchy fog. Lows in the mid 50s. Light and variable winds. |
| Mon Hi: 81°FHi: 27°C Lo: 59°F Lo: 15°C |
Monday... Patchy fog in the morning. Mostly sunny. Highs in the lower 80s. Southwest winds around 5 mph, becoming northwest around 5 mph in the afternoon. |
Tue Hi: 85°FHi: 29°C Lo: 61°F Lo: 16°C |
Tuesday... Mostly sunny. Highs in the mid 80s. Southeast winds around 5 mph. |
| Wed Hi: 89°FHi: 32°C Lo: 65°F Lo: 18°C |
Wednesday... Mostly sunny. Highs in the upper 80s. |
| Thu Hi: 85°FHi: 29°C Lo: 61°F Lo: 16°C |
Thursday... Mostly clear. Highs in the mid 80s. Lows in the lower 60s. |
| Fri Hi: 85°FHi: 29°C Lo: 61°F Lo: 16°C |
Friday... Mostly clear. Highs in the mid 80s. Lows in the lower 60s. |
| Fri Hi: 85°FHi: 29°C Lo: 61°F Lo: 16°C |
Friday... Mostly clear. Highs in the mid 80s. Lows in the lower 60s. |
Sat Hi: 85°FHi: 29°C Lo: 69°F Lo: 21°C |
Saturday... Partly cloudy. Lows in the lower 60s. Highs in the mid 80s. |
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