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LakeQuality

Cedar Island Lake Water Temperature

Cedar Island Lake in St. Louis County, Minnesota averages about 70°F at the surface in summer — warmest in Jul (~72°F) and coldest in May (~56°F). These are typical values by month, not a live reading.

Typical in July
72°F
Comfortable
Summer average
70°F
Warmest (Jul)
72°F
Coldest (May)
56°F

Typical water temperature by month

Jan
Feb
Mar
Apr
May
56°
Jun
69°
Jul
72°
Aug
69°
Sep
63°
Oct
Nov
Dec

Typical surface water temperature by month, from 45 field readings (20192021) via the EPA Water Quality Portal. Months with too few readings are left blank.

Is Cedar Island Lake warm enough to swim?

At its summer peak (~70°F): Comfortable

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

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

Where to stay near Cedar Island Lake

Planning a swim or lake trip? Compare cabins, lodges, and vacation rentals near Cedar Island Lake — live availability and prices.

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Frequently asked questions

What is the water temperature of Cedar Island Lake?

Cedar Island Lake has a typical summer surface temperature of about 70°F. It is usually warmest in July (around 72°F) and coldest in May (around 56°F). These are typical values by month from 45 EPA Water Quality Portal field readings (2019–2021), not a live reading.

When is Cedar Island Lake warmest?

Surface water at Cedar Island Lake is typically warmest in July, reaching about 72°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 Cedar Island Lake warm enough to swim?

At its typical summer peak of about 70°F, Cedar Island Lake rates as "comfortable" for swimming. Pleasant for swimming — the range most people find enjoyable without a wetsuit.

Where does this Cedar Island 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 — 45 readings from 2 monitoring stations between 2019 and 2021. 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.