Lake Mendocino — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lake Mendocino, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lake Mendocino today is 26.9°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
✅ As of today, the minimum water temperature ranges from 79°F (26°C) to 82°F (28°C). This is very warm water, allowing for extended stays without any discomfort. Swimming in these conditions will be particularly enjoyable, making it the ideal temperature range for those who want to relax in the sea. Additionally, water in this temperature range is suitable for children and elderly people, as it is comfortable for prolonged stays. 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 | 25.8°C | 24.6°C | |
| AUG 25 | 25.8°C | 24.6°C | |
| AUG 26 | 25.8°C | 24.6°C | |
| AUG 27 | 26.3°C | 24.6°C | |
| AUG 28 | 26.8°C | 24.6°C | |
| AUG 29 | 26.8°C | 24.6°C | |
| AUG 30 | 26.8°C | 24.6°C | |
| AUG 31 | 26.6°C | 24.6°C | |
| SEP 1 | 21.0°C | 26.6°C | |
| SEP 2 | 21.0°C | 26.3°C | |
| SEP 3 | 21.0°C | 26.0°C | |
| SEP 4 | 21.0°C | 25.7°C | |
| SEP 5 | 21.0°C | 25.4°C | |
| SEP 6 | 21.0°C | 25.1°C | |
| SEP 7 | 21.0°C | 24.8°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 | 8°C | 12°C | 16°C |
| February | 8°C | 11°C | 13°C |
| March | 9°C | 13°C | 17°C |
| April | 11°C | 14°C | 18°C |
| May | 11°C | 17°C | 24°C |
| June | 20°C | 23°C | 27°C |
| July | 19°C | 24°C | 30°C |
| August | 20°C | 25°C | 30°C |
| September | 18°C | 21°C | 24°C |
| October | 14°C | 19°C | 23°C |
| November | 11°C | 14°C | 17°C |
| December | 9°C | 12°C | 15°C |
Lake Mendocino: Water Temperature by Location
Lake Mendocino: Weather Forecast
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September 4
September 5
September 6
Location & Local Information
Lake Mendocino, a reservoir in northern California, experiences noticeable seasonal variation in surface water temperature. In winter months surface readings commonly range from about 40–50°F (4–10°C). Spring brings gradual warming to roughly 50–65°F (10–18°C) as air temperatures rise and inflows moderate. Peak summer surface temperatures often reach approximately 65–75°F (18–24°C) on sunny, calm days, though shallow bays warm more quickly and deeper sections remain significantly cooler. In autumn the lake cools back into the 50–65°F (10–18°C) band. These figures are surface estimates; colder water persists at depth because the reservoir stratifies and inflowing streams can introduce cold water even in summer.
Swimming is generally allowed at Lake Mendocino in designated recreation areas, and people commonly swim during warmer months, but there are restrictions and safety considerations. Authorities may limit access in certain zones for operational, water-quality, or safety reasons, and lifeguards are not always present. Even on hot days, the water can be cold enough to cause cold-shock or rapid loss of body heat, especially outside shallow, sun-warmed areas, so swimmers are advised to use caution, stay close to shore, wear flotation when appropriate, and heed posted rules and warnings.