South Twin Lake Water Temperature
South Twin Lake in Washington County, Minnesota typically sits around 53°F at the surface in October — warmest in Jul (~77°F) and coldest in Apr (~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 (77°F).
Typical surface water temperature by month, from 90 field readings (2010–2024) via the EPA Water Quality Portal. Months with too few readings are left blank.
Is South Twin Lake warm enough to swim?
Pleasant for swimming — the range most people find enjoyable without a wetsuit.
Want more than temperature? South Twin Lake water quality: clarity, algae, phosphorus, depth, fish species, and current advisories, all on one page.
Water temperatures at nearby Minnesota lakes
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Where to stay near South Twin Lake
Planning a swim or lake trip? Compare cabins, lodges, and vacation rentals near South Twin Lake — live availability and prices. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near South Twin Lake
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Frequently asked questions
What is the water temperature of South Twin Lake?
South Twin Lake typically sits around 53°F at the surface in October, from 90 EPA Water Quality Portal field readings (2010–2024). That is a typical value for the month, not a live reading.
When is South Twin Lake warmest?
Surface water at South Twin Lake is typically warmest in July, reaching about 77°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 South Twin Lake warm enough to swim?
At its typical summer peak of about 74°F, South Twin Lake rates as "comfortable" for swimming. Pleasant for swimming — the range most people find enjoyable without a wetsuit.
Where does this South Twin 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 — 90 readings from 3 monitoring stations between 2010 and 2024. 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.