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City of Waterloo, IllinoisWaterloo, IL 7-Day Night Weather Forecast
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Waterloo, IL Weather Forecast
Waterloo, IL Weather Forecast Date: 128 AM CDT Mon Oct 26 2026
The area/counties/county of: Monroe County Il, Jefferson County Mo.or toggle through each period.
Rest of Tonight... Partly cloudy. Near steady temperature in the mid 50s. Light and variable winds.
Monday... Partly sunny. Highs in the mid 70s. Southwest winds around 5 mph.
Monday Night... Partly cloudy. Lows in the upper 40s. South winds around 5 mph.
Tuesday... Partly sunny in the morning, then becoming mostly cloudy. Highs in the mid 70s. South winds around 5 mph.
Tuesday Night... Mostly cloudy in the evening, then becoming partly cloudy. Lows in the lower 50s. South winds around 5 mph.
Wednesday... Sunny. Highs in the upper 70s.
Wednesday Night... Clear. Lows in the lower 50s.
Thursday... Sunny. Highs in the lower 80s.
Thursday Night... Partly cloudy in the evening, then becoming mostly cloudy. Lows in the mid 50s.
Friday... Partly sunny. Highs around 80.
Friday Night... Mostly cloudy. A slight chance of showers in the evening. Lows in the mid 50s. Chance of rain 20%.
Saturday... Mostly cloudy in the morning, then becoming partly sunny. A 40% chance of showers. Highs in the mid 70s.
Saturday Night... Mostly cloudy. A 50% chance of showers. Lows in the mid 50s. Highs in the mid 70s.
POP = Probability of Precipitation
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