Lake Diane Water Temperature
Lake Diane in Hillsdale County, Michigan typically sits around 57°F at the surface in September — warmest in Jul (~60°F) and coldest in May (~53°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 443 field readings (2011–2017) via the EPA Water Quality Portal. Months with too few readings are left blank.
Is Lake Diane warm enough to swim?
Wetsuit territory. Brief exposure is tolerable but prolonged swimming without protection risks hypothermia.
Want more than temperature? Lake Diane scored D on water quality — clarity, algae, phosphorus, depth, fish species, and swimming safety, all on one report card.
Water temperatures at nearby Michigan lakes
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Where to stay near Lake Diane
Planning a swim or lake trip? Compare cabins, lodges, and vacation rentals near Lake Diane — 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 Lake Diane
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Frequently asked questions
What is the water temperature of Lake Diane?
Lake Diane typically sits around 57°F at the surface in September, from 443 EPA Water Quality Portal field readings (2011–2017). That is a typical value for the month, not a live reading.
When is Lake Diane warmest?
Surface water at Lake Diane is typically warmest in July, reaching about 60°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 Lake Diane warm enough to swim?
At its typical summer peak of about 59°F, Lake Diane rates as "cold" for swimming. Wetsuit territory. Brief exposure is tolerable but prolonged swimming without protection risks hypothermia.
Where does this Lake Diane 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 — 443 readings from 1 monitoring station between 2011 and 2017. 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.