Trinity Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Trinity Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Trinity Lake today is 18.7°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 |
|---|---|---|---|
| JUN 2 | 18.8°C | 18.5°C | |
| JUN 3 | 16.5°C | 18.5°C | |
| JUN 4 | 17.3°C | 18.5°C | |
| JUN 5 | 17.7°C | 18.5°C | |
| JUN 6 | 17.7°C | 18.5°C | |
| JUN 7 | 19.8°C | 18.5°C | |
| JUN 8 | 18.9°C | 18.5°C | |
| JUN 10 | 18.5°C | 18.7°C | |
| JUN 11 | 18.5°C | 18.7°C | |
| JUN 12 | 18.5°C | 18.7°C | |
| JUN 13 | 18.5°C | 18.7°C | |
| JUN 14 | 18.5°C | 18.7°C | |
| JUN 15 | 18.5°C | 18.6°C | |
| JUN 16 | 18.5°C | 18.6°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 | 3°C | 6°C | 10°C |
| February | 6°C | 8°C | 11°C |
| March | 4°C | 9°C | 15°C |
| April | 9°C | 12°C | 15°C |
| May | 12°C | 16°C | 20°C |
| June | 15°C | 19°C | 22°C |
| July | 19°C | 22°C | 25°C |
| August | 19°C | 22°C | 25°C |
| September | 15°C | 20°C | 25°C |
| October | 12°C | 17°C | 21°C |
| November | 8°C | 12°C | 15°C |
| December | 4°C | 7°C | 10°C |
Trinity Lake: Water Temperature by Location
Trinity Lake: Weather Forecast
June 9
June 10
June 11
June 12
June 13
Location & Local Information
Trinity Lake, a large reservoir in northern California, typically shows a strong seasonal pattern in surface water temperature. In summer months (June–August) surface temperatures commonly range from about 65–75°F (18–24°C), occasionally edging higher in shallow bays on hot, calm days. Spring (March–May) temperatures are cooler, often 50–65°F (10–18°C) as runoff and cooler air continue to influence the lake. Early fall (September–October) can retain summer warmth in surface layers, roughly 55–70°F (13–21°C), but by late fall and winter (November–February) surface readings usually fall to about 40–50°F (4–10°C). Deeper water remains markedly colder year-round because of the reservoir’s depth and stratification, so overall conditions can change quickly with wind and boat action.
Swimming is generally allowed at Trinity Lake because it is managed for multiple forms of recreation, including bathing in designated areas, but public safety and local regulations shape where and when it’s appropriate. Cold water temperatures, sudden drop-offs, boat traffic, and strong currents near inlets, spillways, or the dam make some spots unsafe, so swimmers should use marked swim beaches, wear flotation if unsure of ability, heed posted signs, and be aware of hypothermia risk from cold surface and deeper water.