Surface water temperature is typically 60°in June and warms to 65 to 70°F (18 to 21°C), during August and September. and never above 39° below 700 ft.)

Surface water temperatures (technically at a depth of 5 feet) have been recorded monthly at the Mid-lake and Index stations from TERC's research vessels since 1968 and from four buoys since 2007. Despite year-to-year and longer cyclical variability, the annual average surface water temperatures show an increasing trend. The average temperature in 1968 was 50.4 °F (10.2 °C).
For 2021, the average surface water temperature was 53.1 °F (11.7 °C), making it the third warmest year on record. The overall rate of warming of the lake surface is 0.39 °F (0.22 °C) per decade.

2020 State of the Lake Report | UC Davis
UC Davis Tahoe Environmental Research Center - TERC Lake Monitoring

Source: UC Davis Tahoe Environmental Research Center

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