Spruce Run Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Spruce Run Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Spruce Run Reservoir today is 22°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
✅ As of today, the minimum water temperature ranges from 68°F (20°C) to 74°F (23°C). The water is warm and pleasant for swimming, and in this range, one can stay in the water for extended periods without the risk of hypothermia. This is the ideal temperature for relaxation, swimming, and water sports. Families with children, as well as outdoor enthusiasts, will enjoy swimming and time spent in the water. For most people, this is the optimal temperature for a comfortable beach experience. It is important to note that these swimming tips and recommendations apply only in good weather. When the air temperature is below 68°F (20°C), and sometimes even below 77°F (25°C), swimming can be unpleasant even with relatively high water temperatures.
Water Temperature Chart Over the Last 30 Days
Table of Daily Sea Temperature Data
| Date | Current | Average | Forecast |
|---|---|---|---|
| SEP 14 | 21.9°C | 22.0°C | |
| SEP 15 | 22.5°C | 22.0°C | |
| SEP 16 | 22.3°C | 22.0°C | |
| SEP 17 | 22.3°C | 22.0°C | |
| SEP 18 | 20.1°C | 22.0°C | |
| SEP 19 | 21.2°C | 22.0°C | |
| SEP 20 | 22.2°C | 22.0°C | |
| SEP 21 | 22.0°C | 22.0°C | |
| SEP 22 | 22.0°C | 22.0°C | |
| SEP 23 | 22.0°C | 22.0°C | |
| SEP 24 | 22.0°C | 22.0°C | |
| SEP 25 | 22.0°C | 22.0°C | |
| SEP 26 | 22.0°C | 22.0°C | |
| SEP 27 | 22.0°C | 22.0°C | |
| SEP 28 | 22.0°C | 22.0°C |
* Current - Actual water temperature value
** Average - Average water temperature on this day in recent years
*** Forecast - Our water temperature forecast
Actual nearshore water temperatures may fluctuate by several degrees from the reported values, especially following heavy rainfall or extended periods of strong winds. Certain wind patterns can cause colder, deeper waters to rise and replace the sun-warmed surface water, leading to noticeable variations.
Our forecast is based on a proprietary mathematical model that considers real-time water temperature changes, historical trends, key weather patterns, wind strength and direction, and air temperature specific to each region. Additionally, we incorporate data from other resorts to enhance accuracy.
Monthly Water Temperature Range (Min, Max & Average)
| Month | Min | Avg | Max |
|---|---|---|---|
| January | 0°C | 4°C | 7°C |
| February | 0°C | 4°C | 7°C |
| March | 1°C | 4°C | 7°C |
| April | 7°C | 14°C | 20°C |
| May | 14°C | 18°C | 22°C |
| June | 15°C | 23°C | 30°C |
| July | 15°C | 24°C | 33°C |
| August | 20°C | 26°C | 31°C |
| September | 19°C | 22°C | 25°C |
| October | 11°C | 15°C | 19°C |
| November | 5°C | 8°C | 11°C |
| December | 2°C | 5°C | 7°C |
Spruce Run Reservoir: Water Temperature by Location
Spruce Run Reservoir: Weather Forecast
September 21
September 22
September 23
September 24
September 25
September 26
Location & Local Information
Spruce Run Reservoir, in Hunterdon County, experiences typical northeastern reservoir temperature patterns. Surface water in winter often hovers around freezing to roughly 32–40°F (0–4°C). In spring it warms through approximately 40–60°F (4–16°C) as runoff and air temperatures rise. By summer, surface temperatures commonly reach about 68–80°F (20–27°C) on warm days, though sheltered coves and deeper water remain cooler. In autumn the lake cools back to roughly 50–65°F (10–18°C). Because the reservoir is relatively deep in places, a thermocline can develop in summer and beneath that layer temperatures stay markedly colder, increasing the risk of cold shock if entering deeper water.
Swimming at Spruce Run is generally not permitted as a primary activity; the reservoir is managed principally for water supply and multiuse recreation such as boating and fishing, and there are no lifeguarded beaches operated by the managing agencies. Restrictions exist to protect drinking-water quality and public safety, including heavy boat traffic, changeable currents and the presence of cold, deep water that can cause hypothermia even on warm days. Visitors seeking to cool off should use approved shore areas for wading where allowed and follow posted regulations and seasonal advisories.