Koonz Lake Water Temperature
Koonz Lake in Shawano County, Wisconsin typically sits around 66°F at the surface in October — warmest in Aug (~75°F) and coldest in May (~49°F). That is a typical value for the month, not a live reading.
Typical water temperature by month
Column height runs from this lake’s coldest month (49°F) to its warmest (75°F).
Typical surface water temperature by month, from 138 field readings (2025–2025) via the EPA Water Quality Portal. Months with too few readings are left blank.
Is Koonz Lake warm enough to swim?
Brisk but swimmable for short dips — most people acclimate after the first few minutes.
Want more than temperature? Koonz Lake water quality: clarity, algae, phosphorus, depth, fish species, and current advisories, all on one page.
Water temperatures at nearby Wisconsin lakes
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Where to stay near Koonz Lake
Planning a swim or lake trip? Compare cabins, lodges, and vacation rentals near Koonz Lake — live availability and prices. Switch the map to Satellite to see the lake and how close each stay is to the water.
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Frequently asked questions
What is the water temperature of Koonz Lake?
Koonz Lake typically sits around 66°F at the surface in October, from 138 EPA Water Quality Portal field readings (2025–2025). That is a typical value for the month, not a live reading.
When is Koonz Lake warmest?
Surface water at Koonz Lake is typically warmest in August, reaching about 75°F. Lake surface temperature lags air temperature by several weeks, so the warmest water usually arrives in mid-to-late summer even though the hottest air can come earlier.
Is Koonz Lake warm enough to swim?
At its typical summer peak of about 66°F, Koonz Lake rates as "cool" for swimming. Brisk but swimmable for short dips — most people acclimate after the first few minutes.
Where does this Koonz Lake water temperature data come from?
Every temperature on this page is a typical (climatological) value computed from real surface-water field readings collected by state and federal agencies and published through the EPA Water Quality Portal — 138 readings from 1 monitoring station between 2025 and 2025. They describe what is typical for each month, not the temperature right now.
About this data
Water temperatures are a climatology — the typical value for each month, averaged from real surface-water field readings collected by state and federal agencies and published through the EPA Water Quality Portal. They tell you what to expect, not the temperature at this moment. Actual conditions vary with recent weather, depth, and time of day.