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LakeQuality
Wildfire smoke turning the setting sun deep red above the treeline on Slim Lake

Indiana Lake Water Temperatures

Typical surface water temperatures for 7 Indiana lakes — about 61°F in October. Lake George runs warmest (~81°F in summer); the statewide summer average is about 78°F. Values are typical by month, not live readings.

7
Lakes with a temperature record
61°F
Typical in October
78°F
Typical summer average
81°F
Warmest: Lake George

Indiana lakes by typical summer water temperature (warmest first)

LakeCountyTypical in OctoberSummer avgWarmestColdest
Lake GeorgeSteuben—81°F85°F (Jul)76°F (Jun)
Pike LakeKosciusko61°F79°F81°F (Jul)52°F (Apr)
Middle Lagoon LakeLake—78°F79°F (Jul)61°F (May)
Big Chapman LakeKosciusko—78°F82°F (Jul)73°F (Jun)
Grand Calumet Lagoon LakeLake—78°F80°F (Aug)68°F (Sep)
Big Barbee LakeKosciusko—76°F81°F (Jul)72°F (Jun)
Syracuse LakeKosciusko—75°F78°F (Jul)72°F (Jun)

Frequently asked questions

Which Indiana lake has the warmest water?

Of the 7 Indiana lakes with a temperature record, Lake George in Steuben County runs warmest, averaging about 81°F at the surface in summer. Colder lakes like Syracuse Lake sit closer to 75°F.

What is a typical October water temperature in Indiana?

Across the Indiana lakes we track, typical October surface temperature averages about 61°F. That is a climatological value from EPA field readings, not the temperature right now. Summer averages about 78°F.

Where does this Indiana water temperature data come from?

Each temperature 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. 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 published through the EPA Water Quality Portal. They tell you what to expect, not the temperature right now.