Grass Lake, IL Weather Forecast
Local 7-day forecast
Rain Showers Likely
Track current conditions, temperature changes, wind, and the full daily outlook for Grass Lake, IL in one place.
Rain showers likely before 4pm, then showers and thunderstorms likely. Mostly cloudy, with a high near 72. Northeast wind 5 to 10 mph. Chance of precipitation is 70%.
Local Weather Overview
This forecast page for Grass Lake, IL is designed for quick trip planning, giving you a clean read on daytime highs, overnight lows, and changing conditions across the upcoming forecast window. Latest sync: Sep 14, 2026 2:46 PM CDT.
The active forecast window currently covers Sep 16 to Sep 20, 2026 for Grass Lake, IL.
Page Snapshot
- Page focus
- city weather
- Forecast window
- Sep 16 to Sep 20, 2026
- Latest sync
- Sep 14, 2026 2:46 PM CDT
- Forecast office
- LOT
- Source
- NOAA / NWS
Daily Outlook
This Week in Grass Lake
Thursday looks like the warmest upcoming period in Grass Lake at 77 degrees F.
Sunday Night is the coolest period ahead with temperatures near 58 degrees F.
The strongest winds are forecast for Wednesday at about 5 to 10 mph NE.
Precipitation is mentioned in 10 upcoming forecast periods.
Forecast Details
- Last updated
- Sep 14, 2026 2:46 PM CDT
- Coverage
- 5 days
- Time zone
- America/Chicago
- Forecast office
- LOT
- Radar station
- KMKX
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
Showers and thunderstorms likely before 7pm, then a chance of showers and thunderstorms between 7pm and 1am, then showers and thunderstorms. Cloudy, with a low around 62. Chance of precipitation is 80%.
Showers and thunderstorms before 1pm. Mostly cloudy, with a high near 77.
A chance of rain showers after 1am. Mostly cloudy, with a low around 60.
A chance of rain showers. Partly sunny, with a high near 76.
Rain showers likely. Mostly cloudy, with a low around 62.
Rain showers likely before 1pm, then showers and thunderstorms likely. Mostly cloudy, with a high near 75.
Showers and thunderstorms likely. Mostly cloudy, with a low around 59.
A chance of rain showers before 1pm, then a slight chance of showers and thunderstorms. Mostly cloudy, with a high near 72.
A chance of showers and thunderstorms. Mostly cloudy, with a low around 58.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Wednesday
Sep 16
|
Rain Showers Likely
|
72°F |
5 to 10 mph
NE
|
|
Wednesday Night
Sep 16
|
Showers And Thunderstorms Likely then Chance Showers And Thunderstorms
|
62°F |
5 to 10 mph
NE
|
|
Thursday
Sep 17
|
Showers And Thunderstorms
|
77°F |
5 to 10 mph
NNE
|
|
Thursday Night
Sep 17
|
Mostly Cloudy then Chance Rain Showers
|
60°F |
0 to 5 mph
NE
|
|
Friday
Sep 18
|
Chance Rain Showers
|
76°F |
0 to 5 mph
E
|
|
Friday Night
Sep 18
|
Rain Showers Likely
|
62°F |
5 mph
SE
|
|
Saturday
Sep 19
|
Rain Showers Likely
|
75°F |
5 to 10 mph
SW
|
|
Saturday Night
Sep 19
|
Showers And Thunderstorms Likely
|
59°F |
5 to 10 mph
NNE
|
|
Sunday
Sep 20
|
Chance Rain Showers then Slight Chance Showers And Thunderstorms
|
72°F |
5 to 10 mph
NE
|
|
Sunday Night
Sep 20
|
Chance Showers And Thunderstorms
|
58°F |
5 to 10 mph
E
|
Nearby Forecasts
Explore weather pages for nearby cities and major places around Grass Lake.