Lake Chetek — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lake Chetek, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lake Chetek today is 18.2°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 | 20.1°C | 17.5°C | |
| SEP 15 | 18.9°C | 17.5°C | |
| SEP 16 | 18.9°C | 17.5°C | |
| SEP 17 | 18.9°C | 17.5°C | |
| SEP 18 | 18.2°C | 17.5°C | |
| SEP 19 | 18.5°C | 17.5°C | |
| SEP 20 | 18.4°C | 17.5°C | |
| SEP 21 | 18.2°C | 17.5°C | |
| SEP 22 | 17.5°C | 18.2°C | |
| SEP 23 | 17.5°C | 18.1°C | |
| SEP 24 | 17.5°C | 18.1°C | |
| SEP 25 | 17.5°C | 18.1°C | |
| SEP 26 | 17.5°C | 18.0°C | |
| SEP 27 | 17.5°C | 18.0°C | |
| SEP 28 | 17.5°C | 18.0°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 | 3°C | 5°C |
| March | 0°C | 3°C | 6°C |
| April | 1°C | 7°C | 13°C |
| May | 9°C | 15°C | 20°C |
| June | 16°C | 19°C | 23°C |
| July | 21°C | 24°C | 27°C |
| August | 19°C | 25°C | 30°C |
| September | 14°C | 18°C | 21°C |
| October | 9°C | 14°C | 19°C |
| November | 2°C | 7°C | 12°C |
| December | 0°C | 3°C | 6°C |
Lake Chetek: Water Temperature by Location
Lake Chetek: Weather Forecast
September 22
September 23
September 24
September 25
Location & Local Information
Lake Chetek in northwestern Wisconsin typically follows seasonal water temperature patterns common to glacial lakes. In spring the lake surface often ranges from about 40–55°F (4–13°C) as snowmelt and cool air keep temperatures low. By midsummer surface temperatures commonly reach 70–80°F (21–27°C), with peak warm spells pushing into the mid-70s to 80°F (24–27°C). A summer thermocline can develop so deeper water remains considerably cooler, often 50–60°F (10–16°C) below the mixed surface layer. In autumn the surface cools back toward roughly 50–60°F (10–16°C) before winter freeze-up reduces the open-water temperature to near 32°F (0°C) and the lake becomes ice-covered.
Swimming is generally allowed during the ice-free season and is popular from late spring through early fall because public beaches and private shorelines are used for recreation. Local authorities monitor water quality and will post advisories if bacterial contamination or blue‑green algae (cyanobacteria) blooms occur; such advisories temporarily restrict swimming for health reasons. Swimmers should also be aware of cold-water risks outside peak summer months, boat traffic, and variable shorelines. During winter, ice and extreme cold make regular swimming unsafe and typically impractical. Some public beaches offer lifeguards in high season, and wearing a life jacket is recommended for weaker swimmers or when boats are nearby.