Gun Lake Water Temperature
Gun Lake in Aitkin County, Minnesota typically sits around 64°F at the surface in September — warmest in Aug (~69°F) and coldest in Apr (~50°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 100 field readings (2016–2025) via the EPA Water Quality Portal. Months with too few readings are left blank.
Is Gun Lake warm enough to swim?
Brisk but swimmable for short dips — most people acclimate after the first few minutes.
Want more than temperature? Gun 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
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Where to stay near Gun Lake
Planning a swim or lake trip? Compare cabins, lodges, and vacation rentals near Gun 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 Gun Lake
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Frequently asked questions
What is the water temperature of Gun Lake?
Gun Lake typically sits around 64°F at the surface in September, from 100 EPA Water Quality Portal field readings (2016–2025). That is a typical value for the month, not a live reading.
When is Gun Lake warmest?
Surface water at Gun Lake is typically warmest in August, reaching about 69°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 Gun Lake warm enough to swim?
At its typical summer peak of about 64°F, Gun Lake rates as "cool" for swimming. Brisk but swimmable for short dips — most people acclimate after the first few minutes.
Where does this Gun 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 — 100 readings from 1 monitoring station between 2016 and 2025. 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.