Grindstone Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Grindstone Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Grindstone Lake today is 23.3°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 | 25.4°C | 24.0°C | |
| AUG 5 | 25.4°C | 24.0°C | |
| AUG 6 | 25.2°C | 24.0°C | |
| AUG 7 | 25.2°C | 24.0°C | |
| AUG 8 | 25.2°C | 24.0°C | |
| AUG 9 | 25.2°C | 24.0°C | |
| AUG 10 | 24.4°C | 24.0°C | |
| AUG 11 | 23.3°C | 24.0°C | |
| AUG 12 | 24.0°C | 23.3°C | |
| AUG 13 | 24.0°C | 23.4°C | |
| AUG 14 | 24.0°C | 23.4°C | |
| AUG 15 | 24.0°C | 23.4°C | |
| AUG 16 | 24.0°C | 23.5°C | |
| AUG 17 | 24.0°C | 23.5°C | |
| AUG 18 | 24.0°C | 23.5°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 | 4°C | 8°C |
| April | 1°C | 6°C | 11°C |
| May | 8°C | 14°C | 19°C |
| June | 15°C | 18°C | 22°C |
| July | 19°C | 23°C | 27°C |
| August | 18°C | 24°C | 30°C |
| September | 14°C | 16°C | 19°C |
| October | 9°C | 14°C | 18°C |
| November | 3°C | 8°C | 13°C |
| December | 0°C | 3°C | 7°C |
Grindstone Lake: Water Temperature by Location
Grindstone Lake: Weather Forecast
August 12
August 13
August 14
August 15
August 16
Location & Local Information
Grindstone Lake in northern Wisconsin follows the seasonal pattern typical of glacial lakes in the region. After ice-out in spring, surface temperatures often rise from the low 40s to mid-60s °F (about 5–18 °C) through May and June as sun and air temperatures warm the water. Peak summer surface temperatures commonly reach the low to upper 70s °F (around 21–26 °C), with shallow bays occasionally climbing into the low 80s °F (27–28 °C) on hot, calm days. By early fall the lake cools back into the 50s–60s °F (10–16 °C) and then drops toward the mid-30s–40s °F (2–6 °C) under and after ice formation in winter when the surface is near freezing (32 °F / 0 °C) and the deeper water is typically closer to 39 °F (4 °C).
Swimming at Grindstone Lake is generally allowed and is a common recreational use in summer because surface temperatures become comfortable for bathing and there are shoreline access points. Seasonal swimming depends on conditions: water that is too cold in spring or late fall poses hypothermia risk, and winter ice cover prevents open-water swimming. As with any inland lake, local water-quality advisories, beach postings, and safety measures (life jackets, supervision, awareness of algae blooms or weather changes) determine when and where it is advisable to swim.