Weather WorldGrass Lake, IL 7-Day Night Weather Forecast
Quick Weather Clicks
Settings
Sun & Moon
Weather Quote O' the Day
Grass Lake, IL Weather Forecast
Grass Lake, IL Weather Forecast Date: 437 AM CDT Sun Oct 04 2026
The area/counties/county of: Mason, including the city of Havana.or toggle through each period.
Today... Sunny. Highs in the upper 70s. Northwest winds 5 to 10 mph.
Tonight... Mostly clear. Lows in the mid 40s. North winds around 5 mph.
Monday... Sunny. Highs in the lower 70s. Northeast winds around 5 mph.
Monday Night... Clear. Lows in the mid 40s. Light and variable winds, becoming southeast around 5 mph after midnight.
Tuesday... Sunny. Highs in the mid 70s. South winds 5 to 10 mph.
Tuesday Night... Clear. Not as cool with lows in the mid 50s.
Wednesday... Mostly clear. Highs in the upper 70s. Lows in the lower 50s.
Thursday... Mostly clear. Highs in the upper 70s. Lows in the lower 50s.
Friday... Mostly clear. Highs in the upper 70s. Lows in the lower 50s.
POP = Probability of Precipitation
Grass Lake Radar Loop
Use the map search tool if you want to place a location marker on the radar map...