Sinissippi Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Sinissippi Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Sinissippi Lake today is 18.7°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 14 | 20.1°C | 20.5°C | |
| SEP 15 | 20.0°C | 20.5°C | |
| SEP 16 | 19.5°C | 20.5°C | |
| SEP 17 | 19.7°C | 20.5°C | |
| SEP 18 | 19.6°C | 20.5°C | |
| SEP 19 | 19.4°C | 20.5°C | |
| SEP 20 | 19.2°C | 20.5°C | |
| SEP 22 | 20.5°C | 18.8°C | |
| SEP 23 | 20.5°C | 18.9°C | |
| SEP 24 | 20.5°C | 19.0°C | |
| SEP 25 | 20.5°C | 19.1°C | |
| SEP 26 | 20.5°C | 19.2°C | |
| SEP 27 | 20.5°C | 19.2°C | |
| SEP 28 | 20.5°C | 19.3°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 | 0°C | 3°C | 6°C |
| March | 1°C | 5°C | 8°C |
| April | 4°C | 9°C | 14°C |
| May | 8°C | 14°C | 20°C |
| June | 16°C | 19°C | 23°C |
| July | 20°C | 25°C | 29°C |
| August | 21°C | 24°C | 27°C |
| September | 17°C | 21°C | 24°C |
| October | 13°C | 17°C | 20°C |
| November | 3°C | 10°C | 16°C |
| December | 0°C | 3°C | 6°C |
Sinissippi Lake: Water Temperature by Location
Sinissippi Lake: Weather Forecast
September 21
September 22
September 23
September 24
September 25
September 26
Location & Local Information
Sinissippi Lake in Wisconsin experiences typical Midwestern seasonal swings in surface water temperature. In winter the surface usually approaches freezing, around 32°F (0°C) and often forms ice cover. Spring warming commonly yields surface temperatures from roughly 40–60°F (4–16°C) as runoff and cooler air keep the lake chilly. By summer the surface often reaches its warmest, frequently between about 68–78°F (20–26°C), and in warm spells can climb toward 80°F (27°C) in shallower areas. Fall sees a gradual cooling back into the 50–65°F (10–18°C) range. Deeper parts of the lake remain noticeably cooler than the surface during stratified summer months, so swimmers moving away from shore will encounter markedly lower temperatures.
Swimming at Sinissippi Lake is generally possible where public access or designated entry points exist, because summer surface temperatures are often within a comfortable recreational range. Whether swimming is permitted depends on local rules, posted advisories, and current water quality; bacterial blooms, runoff events, or safety restrictions can temporarily prohibit swimming. Ice cover in winter makes swimming unsafe. As with any inland lake, users should follow signage, check for water-quality notices from local authorities, and exercise standard safety precautions such as lifejackets for weaker swimmers and avoiding underwater hazards.