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 17.4°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 60°F (15°C) to 65°F (18°C). The water is comfortable for most people, making it an ideal range for water sports enthusiasts. The temperature does not cause significant discomfort, and swimming will be pleasant for the majority. However, it's important to remember that prolonged exposure to the water can still lead to cooling, so it's essential to monitor the time spent in the water, especially for children or elderly people. 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 | 19.4°C | 18.4°C | |
| SEP 15 | 18.5°C | 18.4°C | |
| SEP 16 | 18.5°C | 18.4°C | |
| SEP 17 | 18.6°C | 18.4°C | |
| SEP 18 | 17.4°C | 18.4°C | |
| SEP 19 | 17.8°C | 18.4°C | |
| SEP 20 | 17.7°C | 18.4°C | |
| SEP 21 | 17.4°C | 18.4°C | |
| SEP 22 | 18.4°C | 17.5°C | |
| SEP 23 | 18.4°C | 17.5°C | |
| SEP 24 | 18.4°C | 17.6°C | |
| SEP 25 | 18.4°C | 17.6°C | |
| SEP 26 | 18.4°C | 17.7°C | |
| SEP 27 | 18.4°C | 17.7°C | |
| SEP 28 | 18.4°C | 17.8°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 | 0°C | 2°C | 5°C |
| February | 0°C | 2°C | 5°C |
| March | 0°C | 3°C | 6°C |
| April | 1°C | 6°C | 11°C |
| May | 7°C | 13°C | 20°C |
| June | 16°C | 19°C | 22°C |
| July | 18°C | 23°C | 27°C |
| August | 18°C | 24°C | 30°C |
| September | 14°C | 18°C | 23°C |
| October | 9°C | 14°C | 18°C |
| November | 4°C | 9°C | 14°C |
| December | 0°C | 2°C | 5°C |
Clear Lake: Water Temperature by Location
Clear Lake: Weather Forecast
September 21
September 22
September 23
September 24
September 25
Location & Local Information
Clear Lake in Wisconsin typically follows the seasonal temperature patterns of small northern lakes. In spring the surface water usually runs cool, roughly 40–62°F (4–17°C) as the lake stratifies and warms. Summer surface temperatures commonly rise into the 70s and low 80s Fahrenheit, about 21–28°C, with daily and seasonal variation depending on air temperature and depth. By early fall the surface generally cools to about 50–65°F (10–18°C) as turnover begins. In winter the lake is usually at or near freezing at the surface, roughly 32–39°F (0–4°C) where ice cover develops; subsurface temperatures near 39°F (4°C) persist because of water’s density maximum.
Swimming is generally allowed during the ice-free months and many visitors take advantage of public access points and beaches when surface temperatures are comfortable. Local conditions matter: beaches or shorelines can be subject to water-quality advisories for bacteria or cyanobacterial (blue‑green algae) blooms, and private property or township rules can limit access. Cold spring and late‑fall water can pose cold-shock or hypothermia risks even when air temperatures are warm, while ice cover in winter makes regular swimming unsafe except for organized, well‑managed events. Always check current local guidance before entering the water.