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LakeQuality

Round Lake Water Temperature

Round Lake in Hennepin County, Minnesota averages about 59°F at the surface in summer — warmest in Jul (~60°F) and coldest in Jan (~39°F). These are typical values by month, not a live reading.

Typical in July
60°F
Cool
Summer average
59°F
Warmest (Jul)
60°F
Coldest (Jan)
39°F

Typical water temperature by month

Jan
39°
Feb
39°
Mar
Apr
48°
May
52°
Jun
58°
Jul
60°
Aug
60°
Sep
58°
Oct
53°
Nov
Dec

Typical surface water temperature by month, from 516 field readings (20102025) via the EPA Water Quality Portal. Months with too few readings are left blank.

Is Round Lake warm enough to swim?

At its summer peak (~59°F): Cold

Wetsuit territory. Brief exposure is tolerable but prolonged swimming without protection risks hypothermia.

Want more than temperature? Round Lake scored C on water quality — clarity, algae, phosphorus, depth, fish species, and swimming safety, all on one report card.

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Frequently asked questions

What is the water temperature of Round Lake?

Round Lake has a typical summer surface temperature of about 59°F. It is usually warmest in July (around 60°F) and coldest in January (around 39°F). These are typical values by month from 516 EPA Water Quality Portal field readings (2010–2025), not a live reading.

When is Round Lake warmest?

Surface water at Round Lake is typically warmest in July, reaching about 60°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 Round Lake warm enough to swim?

At its typical summer peak of about 59°F, Round Lake rates as "cold" for swimming. Wetsuit territory. Brief exposure is tolerable but prolonged swimming without protection risks hypothermia.

Where does this Round 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 — 516 readings from 1 monitoring station between 2010 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.