Lake Cushman — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lake Cushman, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lake Cushman today is 18.6°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 24 | 19.2°C | 24.0°C | |
| AUG 25 | 19.0°C | 24.0°C | |
| AUG 26 | 19.1°C | 24.0°C | |
| AUG 27 | 19.2°C | 24.0°C | |
| AUG 28 | 19.2°C | 24.0°C | |
| AUG 29 | 18.8°C | 24.0°C | |
| AUG 30 | 18.8°C | 24.0°C | |
| AUG 31 | 18.6°C | 24.0°C | |
| SEP 1 | 21.0°C | 18.7°C | |
| SEP 2 | 21.0°C | 18.8°C | |
| SEP 3 | 21.0°C | 19.0°C | |
| SEP 4 | 21.0°C | 19.1°C | |
| SEP 5 | 21.0°C | 19.2°C | |
| SEP 6 | 21.0°C | 19.3°C | |
| SEP 7 | 21.0°C | 19.4°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 | 3°C | 6°C |
| February | 3°C | 6°C | 8°C |
| March | 4°C | 8°C | 11°C |
| April | 5°C | 10°C | 15°C |
| May | 10°C | 16°C | 21°C |
| June | 10°C | 17°C | 24°C |
| July | 14°C | 23°C | 31°C |
| August | 18°C | 24°C | 30°C |
| September | 16°C | 21°C | 26°C |
| October | 11°C | 16°C | 20°C |
| November | 6°C | 10°C | 14°C |
| December | 3°C | 7°C | 9°C |
Lake Cushman: Water Temperature by Location
Lake Cushman: Weather Forecast
September 1
September 2
September 3
September 4
September 5
Location & Local Information
Lake Cushman’s water is fed by mountain streams and held behind a reservoir dam, so surface temperatures stay on the cool side and vary with season and weather. In winter the lake commonly runs about 36–44°F (2–7°C) near the surface, spring warms to roughly 45–58°F (7–14°C) as snowmelt and sun increase, summer surface temperatures are most comfortable at about 58–70°F (14–21°C) on warm afternoons, and fall typically falls back into the 45–58°F (7–14°C) range. Temperatures drop quickly with depth and in shaded coves, and releases from the dam or fresh inflows can lower near-shore temps even in summer.
Swimming is generally allowed at Lake Cushman in designated day-use beaches and campground waterfronts because the area is managed for recreation, but users must follow posted rules and seasonal closures. Even in summer the water can feel brisk and carries a hypothermia risk for prolonged exposure, so many swimmers stick to warm afternoons, wear wetsuits for extended swims, and keep close supervision of children. Currents near inlets, sudden depth changes, and cold deeper water are the main safety considerations.