Lake Wisconsin — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lake Wisconsin, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lake Wisconsin today is 22.7°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 |
|---|---|---|---|
| AUG 24 | 21.4°C | 22.9°C | |
| AUG 25 | 21.0°C | 22.9°C | |
| AUG 26 | 18.6°C | 22.9°C | |
| AUG 27 | 18.6°C | 22.9°C | |
| AUG 28 | 20.3°C | 22.9°C | |
| AUG 29 | 21.9°C | 22.9°C | |
| AUG 30 | 21.9°C | 22.9°C | |
| AUG 31 | 22.9°C | 22.9°C | |
| SEP 1 | 20.0°C | 22.6°C | |
| SEP 2 | 20.0°C | 22.4°C | |
| SEP 3 | 20.0°C | 22.3°C | |
| SEP 4 | 20.0°C | 22.2°C | |
| SEP 5 | 20.0°C | 22.0°C | |
| SEP 6 | 20.0°C | 21.9°C | |
| SEP 7 | 20.0°C | 21.8°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 | 3°C | 6°C |
| February | 0°C | 4°C | 7°C |
| March | 3°C | 6°C | 8°C |
| April | 3°C | 9°C | 14°C |
| May | 9°C | 14°C | 20°C |
| June | 16°C | 20°C | 24°C |
| July | 18°C | 24°C | 30°C |
| August | 18°C | 23°C | 27°C |
| September | 16°C | 20°C | 24°C |
| October | 10°C | 15°C | 19°C |
| November | 4°C | 8°C | 11°C |
| December | 0°C | 2°C | 5°C |
Lake Wisconsin: Water Temperature by Location
Lake Wisconsin: Weather Forecast
September 1
September 2
September 3
September 4
September 5
Location & Local Information
Lake Wisconsin, a large reservoir on the Wisconsin River, experiences pronounced seasonal shifts in surface water temperature that affect comfort and swimming conditions. In spring (roughly March–May) surface temperatures typically range from about 40–60°F (4–16°C) as runoff and cool air keep the water brisk. By early summer (June) temperatures commonly rise into the 60s–70s°F (15–24°C), with peak summer (July–August) surface temperatures often reaching about 70–80°F (21–27°C) on warm, calm days. In autumn the water cools back into the 50s–60s°F (10–18°C), and in winter the lake usually approaches freezing at the surface (around 32°F / 0°C) and may develop ice cover.
Swimming in Lake Wisconsin is generally allowed in public access and shoreline areas and is a popular summertime activity because summer surface temperatures are commonly comfortable for bathing. Local parks, beaches and private shorelines are used for recreation, but swimmers should be aware of hazards: boat traffic, sudden depth changes, underwater vegetation, and periodic blue‑green algae (cyanobacteria) blooms can prompt advisories. Water temperature also varies with depth and location, so checking current conditions and posted health or safety notices before swimming is recommended.