Clear Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Clear Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Clear Lake today is 21.6°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
✅ As of today, the minimum water temperature ranges from 68°F (20°C) to 74°F (23°C). The water is warm and pleasant for swimming, and in this range, one can stay in the water for extended periods without the risk of hypothermia. This is the ideal temperature for relaxation, swimming, and water sports. Families with children, as well as outdoor enthusiasts, will enjoy swimming and time spent in the water. For most people, this is the optimal temperature for a comfortable beach experience. 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 3 | 21.0°C | 25.3°C | |
| JUN 4 | 20.6°C | 25.3°C | |
| JUN 5 | 21.0°C | 25.3°C | |
| JUN 6 | 21.1°C | 25.3°C | |
| JUN 7 | 21.7°C | 25.3°C | |
| JUN 8 | 21.7°C | 25.3°C | |
| JUN 10 | 21.6°C | 25.3°C | |
| JUN 11 | 25.3°C | 21.8°C | |
| JUN 12 | 25.3°C | 22.0°C | |
| JUN 13 | 25.3°C | 22.2°C | |
| JUN 14 | 25.3°C | 22.3°C | |
| JUN 15 | 25.3°C | 22.5°C | |
| JUN 16 | 25.3°C | 22.7°C | |
| JUN 17 | 25.3°C | 22.9°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 | 5°C | 8°C | 11°C |
| February | 5°C | 8°C | 11°C |
| March | 6°C | 11°C | 16°C |
| April | 11°C | 14°C | 17°C |
| May | 15°C | 20°C | 24°C |
| June | 20°C | 25°C | 30°C |
| July | 23°C | 26°C | 29°C |
| August | 24°C | 26°C | 29°C |
| September | 22°C | 25°C | 28°C |
| October | 16°C | 20°C | 23°C |
| November | 11°C | 15°C | 18°C |
| December | 6°C | 10°C | 13°C |
Clear Lake: Water Temperature by Location
Clear Lake: Weather Forecast
June 9
June 10
June 11
June 12
June 13
Location & Local Information
Clear Lake in Northern California experiences noticeable seasonal swings in surface water temperature because it is relatively shallow and responds quickly to air temperature. In winter the surface commonly ranges from about 42–55°F (6–13°C). Spring warming typically produces temperatures near 52–65°F (11–18°C). Peak summer surface temperatures often sit between 68–80°F (20–27°C), with occasional warm spells pushing readings into the low 80s°F (around 28°C). During fall the water usually cools back into the 60–72°F (16–22°C) band as air temperatures drop. Deeper or wind‑cooled areas can be several degrees cooler than surface readings, and local conditions such as recent weather, depth, and inflows will affect exact values.
Swimming at Clear Lake is generally allowed and many people swim from parks and private shorelines, but opportunities are conditioned by safety and water quality. Recreational use is sometimes restricted when harmful algal blooms (cyanobacteria) occur—these blooms can produce toxins that make contact or ingestion unsafe—so authorities issue advisories or close access when necessary. Cold water in shoulder seasons presents hypothermia risk as well. In short, swimming is possible much of the year in warmer months, but checking current local water‑quality advisories and observing conditions before entering is important.