Grand Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Grand Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Grand Lake today is 20.5°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
✅ As of today, the minimum water temperature ranges from 68°F (20°C) to 74°F (23°C). The water is warm and pleasant for swimming, and in this range, one can stay in the water for extended periods without the risk of hypothermia. This is the ideal temperature for relaxation, swimming, and water sports. Families with children, as well as outdoor enthusiasts, will enjoy swimming and time spent in the water. For most people, this is the optimal temperature for a comfortable beach experience. 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 |
|---|---|---|---|
| JUL 14 | 18.0°C | 17.1°C | |
| JUL 15 | 20.0°C | 17.1°C | |
| JUL 16 | 20.1°C | 17.1°C | |
| JUL 17 | 20.1°C | 17.1°C | |
| JUL 18 | 20.5°C | 17.1°C | |
| JUL 19 | 20.3°C | 17.1°C | |
| JUL 20 | 20.6°C | 17.1°C | |
| JUL 21 | 20.7°C | 17.1°C | |
| JUL 22 | 17.1°C | 20.3°C | |
| JUL 23 | 17.1°C | 20.2°C | |
| JUL 24 | 17.1°C | 20.0°C | |
| JUL 25 | 17.1°C | 19.8°C | |
| JUL 26 | 17.1°C | 19.7°C | |
| JUL 27 | 17.1°C | 19.5°C | |
| JUL 28 | 17.1°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 | 1°C | 5°C | 9°C |
| February | 1°C | 5°C | 9°C |
| March | 3°C | 6°C | 9°C |
| April | 4°C | 7°C | 10°C |
| May | 4°C | 8°C | 12°C |
| June | 10°C | 13°C | 16°C |
| July | 14°C | 17°C | 21°C |
| August | 15°C | 18°C | 20°C |
| September | 13°C | 16°C | 18°C |
| October | 10°C | 13°C | 15°C |
| November | 3°C | 8°C | 11°C |
| December | 2°C | 6°C | 8°C |
Grand Lake: Water Temperature by Location
Grand Lake: Weather Forecast
July 22
July 23
July 24
July 25
July 26
Location & Local Information
Grand Lake is a high-elevation alpine lake, so its water stays considerably colder than lowland lakes. Surface temperatures in winter fall to freezing and the lake often develops ice; near 32°F (0°C) or lower are common under ice. In spring the surface typically ranges from the low 30s to around the upper 40s °F (1–9°C) as snowmelt continues. In midsummer, when the lake is warmest, surface readings commonly reach roughly 50–65°F (10–18°C) on sunny days, though afternoon winds and deeper pockets remain much colder. Even in summer, water below the surface and in deeper areas remains near or below the 40s °F (4–9°C), so a strong thermocline and sudden chill are possible.
Swimming is permitted in Grand Lake in areas where public access or designated shorelines exist, and people do swim there during the warmer months. Because of the lake’s elevation and cold temperatures, swimming can be uncomfortable and carries a substantial risk of cold-water shock and hypothermia, particularly for prolonged immersion. Visitors should check local signage and conditions, limit time in the water, use flotation or wetsuits if needed, and exercise caution with children and inexperienced swimmers. Weather can change quickly at altitude, so even summer swims require attention to temperature and safety.