Little Grass Valley Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Little Grass Valley Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Little Grass Valley Reservoir today is 20°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 65°F (18°C) to 68°F (20°C). This is already quite warm water, which is ideal for most people. Swimming becomes comfortable, and prolonged stays in the water do not cause discomfort. This temperature is perfect for family trips and for those who prefer warmer water. It is also comfortable for water sports such as surfing or swimming. 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 |
|---|---|---|---|
| AUG 30 | 22.5°C | 22.2°C | |
| AUG 31 | 22.2°C | 22.2°C | |
| SEP 1 | 22.3°C | 21.1°C | |
| SEP 2 | 22.8°C | 21.1°C | |
| SEP 3 | 21.2°C | 21.1°C | |
| SEP 4 | 20.7°C | 21.1°C | |
| SEP 5 | 20.2°C | 21.1°C | |
| SEP 6 | 20.1°C | 21.1°C | |
| SEP 7 | 21.1°C | 20.1°C | |
| SEP 8 | 21.1°C | 20.1°C | |
| SEP 9 | 21.1°C | 20.2°C | |
| SEP 10 | 21.1°C | 20.2°C | |
| SEP 11 | 21.1°C | 20.3°C | |
| SEP 12 | 21.1°C | 20.3°C | |
| SEP 13 | 21.1°C | 20.4°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 | 2°C | 5°C |
| February | 0°C | 3°C | 6°C |
| March | 0°C | 5°C | 11°C |
| April | 0°C | 6°C | 11°C |
| May | 7°C | 12°C | 17°C |
| June | 14°C | 19°C | 22°C |
| July | 19°C | 22°C | 25°C |
| August | 20°C | 22°C | 25°C |
| September | 19°C | 21°C | 24°C |
| October | 13°C | 17°C | 21°C |
| November | 6°C | 11°C | 15°C |
| December | 3°C | 6°C | 8°C |
Little Grass Valley Reservoir: Water Temperature by Location
Little Grass Valley Reservoir: Weather Forecast
September 7
September 8
September 9
September 10
September 11
Location & Local Information
Little Grass Valley Reservoir sits at higher elevation in the northern Sierra Nevada, so its water stays cool for most of the year. Typical seasonal surface-temperature ranges are roughly 32–39°F (0–4°C) in winter when parts of the lake can freeze or hold slushy ice, warming to about 40–55°F (4–13°C) through spring as snowmelt feeds the basin. In summer, on warm, calm afternoons the surface can reach roughly 60–70°F (15–21°C) in sheltered shallows, while deeper water remains markedly colder. Early fall temperatures commonly fall back toward 50–60°F (10–15°C) as air temperatures drop and inflows cool.
Swimming is generally possible and commonly practiced in summer months, but it is done at one’s own risk rather than under supervised conditions. The reservoir is a multiuse body of water with boating and camping, so designated beaches or gently sloping shorelines are the safest places to enter; however, there are often no lifeguards, and cold-water shock, sudden depth changes, submerged hazards, and boat traffic are real concerns. Winter or very early spring swimming is usually impractical and hazardous because of near-freezing water and ice. Visitors should expect brisk conditions and take appropriate precautions like wetsuits, gradual entry, and a buddy system.