Lake SammamishWater Level & Temperature
Lake Sammamish water level & water temperature
Lake Sammamish water level is updated continuously from USGS gauge 12122000 (NGVD29). Typical level elevation is 27 ft. Live reading, 7-day trend, and multi-year history appear below as the data loads.
Lake Sammamish water temperature by month
Lake Sammamish surface water temperature averages from about 42°F in February to 69°F in August over the year, based on a 40-year USGS model (1980–2020). Cold-water caution applies in roughly half the year, when the typical temperature is below 60°F.
Jan
43°
Feb
42°
Mar
45°
Apr
50°
May
58°
Jun
63°
Jul
67°
Aug
69°
Sep
66°
Oct
59°
Nov
49°
Dec
45°
Typical surface temperatures (°F), modeled historical averages (USGS 185k-lake dataset, 1980–2020). Colors flag cold-water risk: blue/amber/red = cool, caution, danger. Live and recent readings appear above where a sensor is available.