Sweeney Lake Water Temperature
Sweeney Lake in Hennepin County, Minnesota averages about 68°F at the surface in summer — warmest in Aug (~71°F) and coldest in Jan (~36°F). These are typical values by month, not a live reading.
Typical water temperature by month
Typical surface water temperature by month, from 196 field readings (2011–2024) via the EPA Water Quality Portal. Months with too few readings are left blank.
Is Sweeney Lake warm enough to swim?
Brisk but swimmable for short dips — most people acclimate after the first few minutes.
Want more than temperature? Sweeney Lake scored B on water quality — clarity, algae, phosphorus, depth, fish species, and swimming safety, all on one report card.
Water temperatures at nearby Minnesota lakes
Explore water temperatures
Where to stay near Sweeney Lake
Planning a swim or lake trip? Compare cabins, lodges, and vacation rentals near Sweeney Lake — live availability and prices.
Top-rated places to stay near Sweeney Lake
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a trip to Sweeney Lake?
Get lake water-quality report cards plus the best cabin & lodging deals near Sweeney Lake — straight to your inbox. No spam, unsubscribe anytime.
Frequently asked questions
What is the water temperature of Sweeney Lake?
Sweeney Lake has a typical summer surface temperature of about 68°F. It is usually warmest in August (around 71°F) and coldest in January (around 36°F). These are typical values by month from 196 EPA Water Quality Portal field readings (2011–2024), not a live reading.
When is Sweeney Lake warmest?
Surface water at Sweeney Lake is typically warmest in August, reaching about 71°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 Sweeney Lake warm enough to swim?
At its typical summer peak of about 68°F, Sweeney Lake rates as "cool" for swimming. Brisk but swimmable for short dips — most people acclimate after the first few minutes.
Where does this Sweeney 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 — 196 readings from 3 monitoring stations between 2011 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.