Crystal Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Crystal Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Crystal Lake today is 19.6°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 | 19.9°C | 17.4°C | |
| SEP 14 | 20.8°C | 17.4°C | |
| SEP 15 | 20.4°C | 17.4°C | |
| SEP 16 | 19.7°C | 17.4°C | |
| SEP 17 | 20.4°C | 17.4°C | |
| SEP 18 | 20.4°C | 17.4°C | |
| SEP 19 | 20.4°C | 17.4°C | |
| SEP 20 | 19.9°C | 17.4°C | |
| SEP 21 | 17.4°C | 19.5°C | |
| SEP 22 | 17.4°C | 19.4°C | |
| SEP 23 | 17.4°C | 19.3°C | |
| SEP 24 | 17.4°C | 19.2°C | |
| SEP 25 | 17.4°C | 19.1°C | |
| SEP 26 | 17.4°C | 18.9°C | |
| SEP 27 | 17.4°C | 18.8°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 | 4°C | 7°C |
| February | 1°C | 5°C | 8°C |
| March | 0°C | 3°C | 6°C |
| April | 2°C | 7°C | 12°C |
| May | 10°C | 17°C | 23°C |
| June | 15°C | 19°C | 23°C |
| July | 20°C | 24°C | 29°C |
| August | 21°C | 24°C | 27°C |
| September | 12°C | 17°C | 23°C |
| October | 13°C | 16°C | 19°C |
| November | 0°C | 6°C | 12°C |
| December | 0°C | 3°C | 6°C |
Crystal Lake: Water Temperature by Location
Crystal Lake: Weather Forecast
September 21
September 22
September 23
September 24
September 25
September 26
Location & Local Information
Crystal Lake in Wisconsin typically follows the seasonal pattern of small northern temperate lakes. In spring the surface water commonly ranges from about 40–60°F (4–15°C) as the lake mixes and warms. By midsummer surface temperatures often reach roughly 68–78°F (20–26°C) on sunny days, with cooler metalimnetic and hypolimnetic layers remaining around 50–60°F (10–15°C) in deeper sections. In early fall temperatures generally fall back toward 45–60°F (7–15°C) as cooling and turnover begin. During winter the lake is usually at or just above freezing beneath ice cover, around 32–39°F (0–4°C), until spring thaw.
Swimming is commonly allowed during the open-water season where public access or private beaches exist because summer surface temperatures become comfortable for recreation and local authorities typically maintain designated swim areas. However, whether swimming is advisable depends on current conditions: water-quality advisories (for example, harmful algal blooms or bacterial contamination), posted local regulations, presence of lifeguards, and weather can all restrict access. Ice swimming is not recommended except in supervised, specifically prepared events due to thin ice and hypothermia risk. Always check local notices and safety information before entering the water.