7-Day Zone Forecast for Grundy County (Text-Only)
NWS Forecast for: Grundy County
Issued by: National Weather Service Chicago, IL
Last Update: 120 PM CDT Sun Jul 26 2026




This Afternoon: Mostly cloudy. Warmer. Highs around 90. Southwest winds 5 to 10 mph. Heat index values up to 102.

Tonight: Partly cloudy in the evening, then becoming mostly cloudy. A slight chance of showers and thunderstorms late in the evening. A chance of showers and thunderstorms after midnight. Humid with lows in the mid 70s. South winds 5 to 10 mph. Chance of precipitation 50 percent. Heat index values up to 102 early in the evening.

Monday: Mostly cloudy in the morning, then becoming partly cloudy. A chance of showers and thunderstorms in the morning. A slight chance of showers and thunderstorms in the afternoon. Humid with highs around 90. South winds 5 to 10 mph, increasing to southwest 10 to 15 mph in the afternoon. Chance of precipitation 50 percent. Heat index values up to 103.

Monday Night: Mostly cloudy in the evening, then becoming partly cloudy. A chance of showers and thunderstorms, mainly in the evening. Humid with lows in the lower 70s. West winds 5 to 10 mph, becoming north after midnight. Chance of precipitation 30 percent. Heat index values up to 101 early in the evening.

Tuesday: Partly cloudy in the morning, then clearing. Humid with highs in the mid 80s. North winds around 10 mph.

Tuesday Night: Clear. Lows in the lower 60s.

Wednesday: Sunny. Highs in the mid 80s.

Wednesday Night: Clear. Lows in the lower 60s.

Thursday: Mostly sunny in the morning, then becoming partly cloudy. Highs in the mid 80s.

Thursday Night: Partly cloudy in the evening, then becoming mostly cloudy. Lows in the upper 60s.

Friday: Mostly cloudy. A chance of showers in the afternoon. Highs in the mid 80s. Chance of precipitation 40 percent.

Friday Night: Mostly cloudy with a chance of showers. Lows in the upper 60s. Chance of precipitation 50 percent.

Saturday: Mostly cloudy in the morning, then becoming partly cloudy. A chance of showers. Highs in the mid 80s. Chance of precipitation 40 percent.







Zone Forecast: Grundy County

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