Lake Kegonsa — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lake Kegonsa, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lake Kegonsa today is 19.7°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 13 | 19.7°C | 21.0°C | |
| SEP 14 | 20.4°C | 21.0°C | |
| SEP 15 | 20.3°C | 21.0°C | |
| SEP 16 | 20.2°C | 21.0°C | |
| SEP 17 | 20.2°C | 21.0°C | |
| SEP 18 | 20.1°C | 21.0°C | |
| SEP 19 | 19.9°C | 21.0°C | |
| SEP 20 | 19.8°C | 21.0°C | |
| SEP 21 | 21.0°C | 19.8°C | |
| SEP 22 | 21.0°C | 19.8°C | |
| SEP 23 | 21.0°C | 19.9°C | |
| SEP 24 | 21.0°C | 20.0°C | |
| SEP 25 | 21.0°C | 20.0°C | |
| SEP 26 | 21.0°C | 20.1°C | |
| SEP 27 | 21.0°C | 20.2°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 | 4°C |
| February | 1°C | 3°C | 6°C |
| March | 2°C | 5°C | 9°C |
| April | 5°C | 9°C | 14°C |
| May | 10°C | 15°C | 20°C |
| June | 16°C | 20°C | 23°C |
| July | 19°C | 25°C | 30°C |
| August | 21°C | 24°C | 27°C |
| September | 18°C | 21°C | 24°C |
| October | 9°C | 14°C | 19°C |
| November | 2°C | 6°C | 10°C |
| December | 0°C | 3°C | 6°C |
Lake Kegonsa: Water Temperature by Location
Lake Kegonsa: Weather Forecast
September 21
September 22
September 23
September 24
September 25
Location & Local Information
Lake Kegonsa’s water temperatures follow the seasonal patterns typical of southern Wisconsin lakes. In spring the lake is cool as it mixes and warms, generally ranging from about 40–60°F (4–15°C). Surface temperatures climb in summer, often reaching the low to mid 70s up to the low 80s Fahrenheit (about 21–28°C) on warm July and August afternoons; deeper water remains noticeably cooler. In early fall the surface usually cools back into the 60s °F (15–20°C) before dropping through the 50s (10–15°C) and toward near‑freezing under ice in winter, when surface measurements can be around 32–34°F (0–1°C) if the lake is frozen over.
Swimming in Lake Kegonsa is generally allowed and is popular in the warm months because surface temperatures frequently reach comfortable levels (around 70°F/21°C and above). Designated swimming areas at parks and public access sites provide safer spots for recreation, but conditions can change: shore advisories or closures sometimes occur due to harmful algal blooms or bacterial contamination, and ice on the lake in winter presents obvious hazards. Visitors should check local notices about water quality and ice safety before entering the water, and be aware that deeper or wind‑exposed areas remain cooler than sheltered shallows.