Grays Bay — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Grays Bay, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Grays Bay today is 19°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 | 21.7°C | 20.6°C | |
| SEP 15 | 21.4°C | 20.6°C | |
| SEP 16 | 20.5°C | 20.6°C | |
| SEP 17 | 19.1°C | 20.6°C | |
| SEP 18 | 19.1°C | 20.6°C | |
| SEP 19 | 19.2°C | 20.6°C | |
| SEP 20 | 19.5°C | 20.6°C | |
| SEP 21 | 19.0°C | 20.6°C | |
| SEP 22 | 20.6°C | 19.1°C | |
| SEP 23 | 20.6°C | 19.2°C | |
| SEP 24 | 20.6°C | 19.2°C | |
| SEP 25 | 20.6°C | 19.3°C | |
| SEP 26 | 20.6°C | 19.4°C | |
| SEP 27 | 20.6°C | 19.5°C | |
| SEP 28 | 20.6°C | 19.6°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 | 3°C | 6°C |
| March | 0°C | 3°C | 7°C |
| April | 3°C | 8°C | 14°C |
| May | 10°C | 16°C | 22°C |
| June | 17°C | 22°C | 27°C |
| July | 22°C | 25°C | 28°C |
| August | 20°C | 24°C | 28°C |
| September | 18°C | 21°C | 23°C |
| October | 6°C | 13°C | 19°C |
| November | 3°C | 7°C | 11°C |
| December | 1°C | 5°C | 8°C |
Grays Bay: Water Temperature by Location
Grays Bay: Weather Forecast
September 21
September 22
September 23
September 24
September 25
September 26
Location & Local Information
Grays Bay, like many lakes and bays in Minnesota, follows strong seasonal temperature swings. In spring the surface waters typically run cool, often around 40–60 °F (4–16 °C) as the lake mixes and warms. Summer surface temperatures in sheltered, shallow areas commonly reach about 68–78 °F (20–26 °C) on warm afternoons, while deeper or wind‑exposed parts stay several degrees cooler. In autumn the water cools back to roughly 45–60 °F (7–16 °C) before ice forms; during winter the bay is usually at or just above freezing under ice cover, around 32–39 °F (0–4 °C) for liquid water beneath the ice. These are typical ranges for midwestern lakes and will vary with depth, weather and year‑to‑year conditions.
Swimming in Grays Bay is generally possible during the warmer months where public access or private shoreline allows it, primarily because summer surface temperatures become comfortable for recreational use. However, local rules, beach postings and water‑quality advisories can restrict swimming at times — for example during high bacterial counts, harmful algal blooms, or unsafe currents. In winter, swimming is not recommended because of ice hazards and very cold water temperatures; only organised and well‑supervised ice swimming with appropriate safety measures should be attempted. Always check current local advisories and conditions before entering the water.