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LakeQuality

Loon Lake Deep Water Temperature

Loon Lake Deep in Cook County, Minnesota averages about 72°F at the surface in summer — warmest in Jun (~75°F) and coldest in Oct (~53°F). These are typical values by month, not a live reading.

Typical in July
72°F
Comfortable
Summer average
72°F
Warmest (Jun)
75°F
Coldest (Oct)
53°F

Typical water temperature by month

Jan
Feb
Mar
Apr
May
59°
Jun
75°
Jul
72°
Aug
69°
Sep
64°
Oct
53°
Nov
Dec

Typical surface water temperature by month, from 58 field readings (20102022) via the EPA Water Quality Portal. Months with too few readings are left blank.

Is Loon Lake Deep warm enough to swim?

At its summer peak (~72°F): Comfortable

Pleasant for swimming — the range most people find enjoyable without a wetsuit.

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

Where to stay near Loon Lake Deep

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Frequently asked questions

What is the water temperature of Loon Lake Deep?

Loon Lake Deep has a typical summer surface temperature of about 72°F. It is usually warmest in June (around 75°F) and coldest in October (around 53°F). These are typical values by month from 58 EPA Water Quality Portal field readings (2010–2022), not a live reading.

When is Loon Lake Deep warmest?

Surface water at Loon Lake Deep is typically warmest in June, 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 Loon Lake Deep warm enough to swim?

At its typical summer peak of about 72°F, Loon Lake Deep rates as "comfortable" for swimming. Pleasant for swimming — the range most people find enjoyable without a wetsuit.

Where does this Loon Lake Deep 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 — 58 readings from 4 monitoring stations between 2010 and 2022. 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.