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LakeQuality

Mary Lake Water Temperature

Mary Lake in Wright County, Minnesota averages about 62°F at the surface in summer — warmest in Sep (~64°F) and coldest in May (~53°F). These are typical values by month, not a live reading.

Typical in July
62°F
Cool
Summer average
62°F
Warmest (Sep)
64°F
Coldest (May)
53°F

Typical water temperature by month

Jan
Feb
Mar
Apr
May
53°
Jun
60°
Jul
62°
Aug
63°
Sep
64°
Oct
60°
Nov
Dec

Typical surface water temperature by month, from 145 field readings (20112023) via the EPA Water Quality Portal. Months with too few readings are left blank.

Is Mary Lake warm enough to swim?

At its summer peak (~62°F): Cool

Brisk but swimmable for short dips — most people acclimate after the first few minutes.

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

Where to stay near Mary Lake

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Frequently asked questions

What is the water temperature of Mary Lake?

Mary Lake has a typical summer surface temperature of about 62°F. It is usually warmest in September (around 64°F) and coldest in May (around 53°F). These are typical values by month from 145 EPA Water Quality Portal field readings (2011–2023), not a live reading.

When is Mary Lake warmest?

Surface water at Mary Lake is typically warmest in September, reaching about 64°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 Mary Lake warm enough to swim?

At its typical summer peak of about 62°F, Mary Lake rates as "cool" for swimming. Brisk but swimmable for short dips — most people acclimate after the first few minutes.

Where does this Mary 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 — 145 readings from 1 monitoring station between 2011 and 2023. 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.