Saint Johns Lake Water Temperature
Saint Johns Lake in Kandiyohi County, Minnesota typically sits around 58°F at the surface in September — warmest in Jul (~81°F) and coldest in Sep (~58°F). That is a typical value for the month, not a live reading.
Typical water temperature by month
Typical surface water temperature by month, from 32 field readings (2010–2023) via the EPA Water Quality Portal. Months with too few readings are left blank.
Is Saint Johns Lake warm enough to swim?
Pleasant for swimming — the range most people find enjoyable without a wetsuit.
Want more than temperature? Saint Johns Lake scored NR on water quality — clarity, algae, phosphorus, depth, fish species, and swimming safety, all on one report card.
Water temperatures at nearby Minnesota lakes
Summer average ~74°F
Summer average ~77°F
Summer average ~73°F
Summer average ~74°F
Summer average ~76°F
Summer average ~75°F
Explore water temperatures
Where to stay near Saint Johns Lake
Planning a swim or lake trip? Compare cabins, lodges, and vacation rentals near Saint Johns Lake — live availability and prices. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Saint Johns Lake
Prices for Sep 4–6, 4 adults. Change dates on the map below.
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Frequently asked questions
What is the water temperature of Saint Johns Lake?
Saint Johns Lake typically sits around 58°F at the surface in September, from 32 EPA Water Quality Portal field readings (2010–2023). That is a typical value for the month, not a live reading.
When is Saint Johns Lake warmest?
Surface water at Saint Johns Lake is typically warmest in July, reaching about 81°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 Saint Johns Lake warm enough to swim?
At its typical summer peak of about 75°F, Saint Johns Lake rates as "comfortable" for swimming. Pleasant for swimming — the range most people find enjoyable without a wetsuit.
Where does this Saint Johns 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 — 32 readings from 1 monitoring station between 2010 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.