Lake HopatcongWater Level & Temperature
Lake Hopatcong water level & water temperature
Lake Hopatcong water level is updated continuously from the operating agency. Typical level elevation is 924.5 ft. Live reading, 7-day trend, and multi-year history appear below as the data loads.
Lake Hopatcong water temperature by month
Lake Hopatcong surface water temperature averages from about 36°F in January to 80°F in July 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
36°
Feb
37°
Mar
41°
Apr
51°
May
64°
Jun
74°
Jul
80°
Aug
79°
Sep
73°
Oct
61°
Nov
48°
Dec
39°
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.