Upper Saint Croix Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Upper Saint Croix Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Upper Saint Croix Lake today is 23.4°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
✅ As of today, the minimum water temperature ranges from 75°F (23°C) to 79°F (26°C). This is a very comfortable temperature for swimming, and many people can enjoy prolonged stays in the water without feeling cold. The water is pleasantly warm, making it ideal for relaxation and water sports. This temperature range is particularly popular among tourists, as it combines comfort and safety for health. 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 4 | 25.9°C | 24.5°C | |
| AUG 5 | 25.9°C | 24.5°C | |
| AUG 6 | 25.7°C | 24.5°C | |
| AUG 7 | 25.7°C | 24.5°C | |
| AUG 8 | 25.7°C | 24.5°C | |
| AUG 9 | 25.7°C | 24.5°C | |
| AUG 10 | 23.9°C | 24.5°C | |
| AUG 11 | 23.4°C | 24.5°C | |
| AUG 12 | 24.5°C | 23.5°C | |
| AUG 13 | 24.5°C | 23.5°C | |
| AUG 14 | 24.5°C | 23.6°C | |
| AUG 15 | 24.5°C | 23.6°C | |
| AUG 16 | 24.5°C | 23.7°C | |
| AUG 17 | 24.5°C | 23.7°C | |
| AUG 18 | 24.5°C | 23.8°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 | 7°C |
| February | 0°C | 3°C | 6°C |
| March | 0°C | 3°C | 7°C |
| April | 1°C | 6°C | 12°C |
| May | 6°C | 13°C | 19°C |
| June | 15°C | 18°C | 22°C |
| July | 19°C | 23°C | 27°C |
| August | 19°C | 25°C | 30°C |
| September | 14°C | 16°C | 19°C |
| October | 9°C | 14°C | 18°C |
| November | 2°C | 8°C | 13°C |
| December | 0°C | 3°C | 7°C |
Upper Saint Croix Lake: Water Temperature by Location
Upper Saint Croix Lake: Weather Forecast
August 12
August 13
August 14
August 15
August 16
Location & Local Information
Upper Saint Croix Lake in Wisconsin typically follows the seasonal temperature patterns of shallow northern lakes. In spring, as ice breaks up and air temperatures rise, surface water commonly ranges from about 45–60°F (7–16°C). Summer afternoons often produce the warmest readings, with surface temperatures usually between 68–78°F (20–26°C) in July and August, although shallow bays can warm a few degrees higher on calm, sunny days. By early autumn surface temperatures fall back into the mid-50s to low 70s°F (13–22°C) as cooling weather and increased mixing set in. In winter the lake is generally ice-covered and surface temperatures approach freezing around 32°F (0°C), with liquid water beneath the ice tending toward the typical near-4°C density maximum in deeper spots.
Swimming is generally allowed and is most common in summer when surface temperatures are comfortable for recreational use. Public access points and private shorelines offer places to enter the water, but seasonal factors influence safety and enjoyment: cold springs and sudden weather changes can make swimming hazardous, and late-summer algae or shoreline runoff occasionally affect water quality. In winter, swimming is not safe under normal conditions once ice forms, except for organized ice-swimming activities conducted with appropriate safety measures. Always check local advisories and conditions before entering the water.