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LakeQuality

Thomas Lake Water Temperature

Thomas Lake in Hennepin County, Minnesota averages about 57°F at the surface in summer — warmest in Aug (~59°F) and coldest in Apr (~40°F). These are typical values by month, not a live reading.

Typical in July
58°F
Cold
Summer average
57°F
Warmest (Aug)
59°F
Coldest (Apr)
40°F

Typical water temperature by month

Jan
Feb
Mar
Apr
40°
May
53°
Jun
55°
Jul
58°
Aug
59°
Sep
59°
Oct
58°
Nov
Dec

Typical surface water temperature by month, from 109 field readings (20212022) via the EPA Water Quality Portal. Months with too few readings are left blank.

Is Thomas Lake warm enough to swim?

At its summer peak (~57°F): Cold

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

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

Where to stay near Thomas Lake

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Frequently asked questions

What is the water temperature of Thomas Lake?

Thomas Lake has a typical summer surface temperature of about 57°F. It is usually warmest in August (around 59°F) and coldest in April (around 40°F). These are typical values by month from 109 EPA Water Quality Portal field readings (2021–2022), not a live reading.

When is Thomas Lake warmest?

Surface water at Thomas Lake is typically warmest in August, reaching about 59°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 Thomas Lake warm enough to swim?

At its typical summer peak of about 57°F, Thomas Lake rates as "cold" for swimming. Wetsuit territory. Brief exposure is tolerable but prolonged swimming without protection risks hypothermia.

Where does this Thomas 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 — 109 readings from 1 monitoring station between 2021 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.