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Flat Lake, IL Weather Forecast
Flat Lake, IL Weather Forecast Date: 453 PM CST Thu Nov 12 2026
The area/counties/county of: Greene County Il, Jersey County Il.or toggle through each period.
Tonight... Partly cloudy this evening, then clearing. Cooler with lows around 30. Northwest winds 10 to 15 mph.
Friday... Mostly sunny. Highs in the mid 40s. North winds 10 to 15 mph.
Friday Night... Mostly clear. Lows in the mid 20s. North winds around 5 mph.
Saturday... Sunny. Highs in the upper 40s. North winds around 5 mph.
Saturday Night... Clear. Lows in the mid 20s. Light and variable winds.
Sunday... Mostly clear. Highs around 50. Lows in the upper 20s.
Sunday Night... Mostly clear. Highs around 50. Lows in the upper 20s.
Monday... Clear. Highs in the lower 50s. Lows in the upper 20s.
Tuesday... Clear. Highs in the lower 50s. Lows in the upper 20s.
Wednesday... Sunny. Highs in the upper 50s.
Wednesday Night... Partly cloudy. Lows in the upper 30s.
POP = Probability of Precipitation
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