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New Castle, IL Weather Forecast
New Castle, IL Weather Forecast Date: 903 PM CST Tue Mar 03 2026
The area/counties/county of: Williamson, including the city of Herrin.or toggle through each period.
Tonight... Mostly cloudy. A chance of showers and thunderstorms after midnight. Not as cool with lows in the upper 50s. South winds 10 to 15 mph. Chance of rain 50%.
Wednesday... Showers likely with a chance of thunderstorms in the morning, then showers with a slight chance of thunderstorms in the afternoon. Highs in the lower 70s. Southwest winds 5 to 10 mph. Chance of rain 80%.
Wednesday Night... A chance of thunderstorms. Showers. Lows in the upper 50s. South winds 5 to 10 mph. Chance of rain 90%.
Thursday... Showers in the morning, then showers likely with a chance of thunderstorms in the afternoon. Highs in the lower 70s. Southwest winds 5 to 10 mph. Chance of rain 90%.
Thursday Night... Mostly cloudy with a chance of showers. Lows in the upper 50s. South winds 5 to 10 mph. Chance of rain 40%.
Friday... Partly sunny. Highs in the upper 70s.
Friday Night... Mostly cloudy. Showers likely with a chance of thunderstorms after midnight. Lows in the lower 60s. Chance of rain 70%.
Saturday... Mostly cloudy. Showers, mainly in the morning. Highs in the lower 70s. Chance of rain 90%.
Saturday Night... Partly cloudy. Lows in the upper 40s. Highs in the upper 60s.
Sunday... Partly cloudy. Lows in the upper 40s. Highs in the upper 60s.
Sunday Night... Mostly clear. Lows in the lower 50s. Highs in the mid 70s.
Monday... Mostly clear. Lows in the lower 50s. Highs in the mid 70s.
Monday Night... Mostly clear with a chance of showers. Lows in the upper 50s. Chance of rain 30%.
POP = Probability of Precipitation
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