Lake Entiat — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lake Entiat, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lake Entiat today is 19.9°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 |
|---|---|---|---|
| SEP 14 | 19.8°C | 19.0°C | |
| SEP 15 | 19.9°C | 19.0°C | |
| SEP 16 | 19.8°C | 19.0°C | |
| SEP 17 | 19.7°C | 19.0°C | |
| SEP 18 | 19.5°C | 19.0°C | |
| SEP 19 | 19.5°C | 19.0°C | |
| SEP 20 | 20.0°C | 19.0°C | |
| SEP 21 | 19.9°C | 19.0°C | |
| SEP 22 | 19.0°C | 19.9°C | |
| SEP 23 | 19.0°C | 19.8°C | |
| SEP 24 | 19.0°C | 19.8°C | |
| SEP 25 | 19.0°C | 19.7°C | |
| SEP 26 | 19.0°C | 19.7°C | |
| SEP 27 | 19.0°C | 19.6°C | |
| SEP 28 | 19.0°C | 19.6°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 | 0°C | 1°C | 4°C |
| February | 0°C | 2°C | 5°C |
| March | 1°C | 4°C | 8°C |
| April | 3°C | 8°C | 13°C |
| May | 7°C | 12°C | 18°C |
| June | 12°C | 17°C | 22°C |
| July | 16°C | 21°C | 26°C |
| August | 20°C | 23°C | 26°C |
| September | 16°C | 19°C | 22°C |
| October | 10°C | 14°C | 18°C |
| November | 5°C | 9°C | 12°C |
| December | 1°C | 4°C | 7°C |
Lake Entiat: Water Temperature by Location
Lake Entiat: Weather Forecast
September 21
September 22
September 23
September 24
September 25
September 26
Location & Local Information
Lake Entiat, the reservoir on the Columbia River behind Rocky Reach Dam in Washington, experiences a wide range of water temperatures through the year. In winter the surface often sits around 39–45°F (4–7°C), spring typically warms to about 45–59°F (7–15°C), summer surface temperatures in shallow, sun-exposed areas can reach roughly 60–75°F (16–24°C), and fall generally drops back into the 50–60°F (10–16°C) range. These are broad seasonal averages; deeper water and shaded or fast-moving channels remain substantially colder than surface readings, and temperatures can vary with local weather, inflows and reservoir operations.
Recreational swimming is generally allowed at public access sites and parks along Lake Entiat, and the lake is used for swimming, boating and other water recreation. However, swimmers should heed posted rules and avoid restricted zones near the dam, boat ramps and navigation channels. Main concerns are cold-water shock even on warm days, boat traffic, sudden drop-offs and typically limited lifeguard coverage, so using designated swim areas, wearing a life jacket when appropriate and checking local notices before entering the water are important for safety.