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Number 2 Portal Lake, IL 7-Day Night Weather Forecast
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Number 2 Portal Lake, IL Weather Forecast
Number 2 Portal Lake, IL Weather Forecast Date: 913 PM CDT Tue Sep 01 2026
The area/counties/county of: Jefferson, including the city of Mount Vernon.or toggle through each period.
Tonight... Clear. Lows in the mid 70s. South winds around 5 mph.
Wednesday... Sunny, hot with highs around 100. Southwest winds 5 to 10 mph.
Wednesday Night... Clear. Lows in the upper 70s. South winds around 5 mph.
Thursday... Sunny, hot with highs around 100. Southwest winds around 5 mph.
Thursday Night... Clear. Lows in the mid 70s. South winds around 5 mph in the evening, becoming light and variable.
Friday... Mostly clear. Hot. Highs around 100. Lows in the mid 70s.
Saturday... Mostly clear. Hot. Highs around 100. Lows in the mid 70s.
Saturday Night... Partly cloudy. Hot. Lows in the lower 70s. Highs in the mid 90s.
Sunday... Partly cloudy. Hot. Lows in the lower 70s. Highs in the mid 90s.
Sunday Night... Mostly clear. Lows in the upper 60s. Highs in the lower 90s.
Labor Day... Mostly clear. Lows in the upper 60s. Highs in the lower 90s.
Monday Night... Partly cloudy. Lows in the upper 60s. Highs in the lower 90s.
POP = Probability of Precipitation
Number 2 Portal Lake Radar Loop
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