Lake Granby — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lake Granby, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lake Granby today is 20.8°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 | 18.5°C | 18.0°C | |
| JUL 15 | 20.4°C | 18.0°C | |
| JUL 16 | 20.4°C | 18.0°C | |
| JUL 17 | 20.4°C | 18.0°C | |
| JUL 18 | 20.9°C | 18.0°C | |
| JUL 19 | 20.7°C | 18.0°C | |
| JUL 20 | 20.9°C | 18.0°C | |
| JUL 21 | 21.0°C | 18.0°C | |
| JUL 22 | 18.0°C | 20.7°C | |
| JUL 23 | 18.0°C | 20.5°C | |
| JUL 24 | 18.0°C | 20.4°C | |
| JUL 25 | 18.0°C | 20.2°C | |
| JUL 26 | 18.0°C | 20.1°C | |
| JUL 27 | 18.0°C | 20.0°C | |
| JUL 28 | 18.0°C | 19.8°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 | 1°C | 3°C | 6°C |
| February | 1°C | 3°C | 6°C |
| March | 3°C | 6°C | 9°C |
| April | 1°C | 5°C | 9°C |
| May | 4°C | 8°C | 13°C |
| June | 8°C | 12°C | 17°C |
| July | 14°C | 18°C | 22°C |
| August | 14°C | 16°C | 19°C |
| September | 11°C | 15°C | 18°C |
| October | 8°C | 12°C | 15°C |
| November | 5°C | 8°C | 11°C |
| December | 2°C | 6°C | 9°C |
Lake Granby: Water Temperature by Location
Lake Granby: Weather Forecast
July 22
July 23
July 24
July 25
July 26
Location & Local Information
Lake Granby is a high-elevation reservoir fed largely by snowmelt, so its water stays cool for most of the year. Surface temperatures typically hover near freezing in winter (around 32°F / 0°C), with the lake often forming ice. In spring and early summer the surface warms gradually, commonly ranging from roughly 35–50°F (2–10°C). On warm summer afternoons the shallow surface can reach about 60–68°F (15–20°C) in sheltered areas, but deeper water remains much colder year-round. During fall the surface cools back toward spring values as weather turns colder.
Swimming is generally possible in the warmer months, but it is limited by cold water and local rules or access points rather than an absolute prohibition. Because the reservoir is large, has boat traffic and few lifeguarded beaches, swimmers should exercise caution: cold-water shock and rapid loss of body heat are the primary hazards even when air temperatures are pleasant. Many visitors prefer shorter dips, wetsuits, or swimming in more protected, shallow bays when conditions allow. In winter the lake is not suitable for conventional swimming due to ice and near-freezing water temperatures.