Updated
Grass Lake
Lake
Comfortable for a swim today
Good to swimComfortable for a swim today: water temperature is 74°F, within the comfortable 70–86°F range.
- Water temperature is 74°F, within the comfortable 70–86°F range.
- Heavy rain today can raise bacteria levels near outfalls and river mouths.
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Comfortable for a swim today
Good to swimComfortable for a swim today: water temperature is 74°F, within the comfortable 70–86°F range.
- Water temperature is 74°F, within the comfortable 70–86°F range. — NOAA buoy 45186, as of Aug 22, 2:40 AM UTC
- Heavy rain today can raise bacteria levels near outfalls and river mouths.
No official beach-advisory feed for Illinois yet — follow posted signs and local guidance.
Live data from NOAA buoy 45186 (19.4 mi away), as of Aug 22, 2:40 AM UTC.
Weather at Grass Lake
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Frequently asked questions
- Where is Grass Lake?
- Grass Lake is a lake in Illinois.
- What is the water temperature at Grass Lake?
- As of August 22, 2026, the water temperature at Grass Lake in Illinois is 74°F (23°C), measured by NOAA buoy 45186, 19.4 miles away.
- Can you swim at Grass Lake?
- Comfortable for a swim today: water temperature is 74°F, within the comfortable 70–86°F range. Checked August 22, 2026.
- What amenities does Grass Lake have?
- Visitor-listed amenities at Grass Lake include camping-nearby.
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- ›Obtain required fishing licenses before arrival
- ›Be aware of lake-specific regulations and restrictions
- ›Monitor water quality reports before swimming
Location & Contact
Illinois
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