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Lake Jaycee, IL 7-Day Night Weather Forecast
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Lake Jaycee, IL Weather Forecast
Lake Jaycee, IL Weather Forecast Date: 127 AM CDT Thu Sep 03 2026
The area/counties/county of: Jefferson, including the city of Mount Vernon.or toggle through each period.
Overnight... Clear. Near steady temperature in the mid 70s. Calm winds.
Thursday... Sunny, hot with highs in the upper 90s. 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... Sunny, hot with highs in the upper 90s. Southwest winds around 5 mph. Highest heat index readings heat index readings up to 105 in the afternoon.
Friday Night... Mostly clear. Lows in the mid 70s. Southwest winds around 5 mph in the evening, becoming light and variable.
Saturday... Mostly clear. Hot. Highs in the mid 90s. Lows in the lower 70s.
Sunday... Mostly clear. Hot. Highs in the mid 90s. Lows in the lower 70s.
Sunday Night... Mostly clear. Lows in the upper 60s. Highs in the mid 90s.
Monday... Mostly clear. Lows in the upper 60s. Highs in the mid 90s.
Tuesday... Mostly clear. Lows in the upper 60s. Highs in the mid 90s.
Tuesday Night... Mostly clear. Hot. Lows in the mid 70s. Highs in the upper 90s.
POP = Probability of Precipitation
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