Grayrocks Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Grayrocks Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Grayrocks Reservoir today is 15.2°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 60°F (15°C) to 65°F (18°C). The water is comfortable for most people, making it an ideal range for water sports enthusiasts. The temperature does not cause significant discomfort, and swimming will be pleasant for the majority. However, it's important to remember that prolonged exposure to the water can still lead to cooling, so it's essential to monitor the time spent in the water, especially for children or elderly people. 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 |
|---|---|---|---|
| OCT 5 | 16.5°C | 14.0°C | |
| OCT 6 | 16.0°C | 14.0°C | |
| OCT 7 | 16.4°C | 14.0°C | |
| OCT 8 | 16.3°C | 14.0°C | |
| OCT 9 | 15.6°C | 14.0°C | |
| OCT 10 | 15.6°C | 14.0°C | |
| OCT 11 | 15.5°C | 14.0°C | |
| OCT 12 | 15.4°C | 14.0°C | |
| OCT 13 | 14.0°C | 15.1°C | |
| OCT 14 | 14.0°C | 15.1°C | |
| OCT 15 | 14.0°C | 15.0°C | |
| OCT 16 | 14.0°C | 15.0°C | |
| OCT 17 | 14.0°C | 14.9°C | |
| OCT 18 | 14.0°C | 14.8°C | |
| OCT 19 | 14.0°C | 14.8°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 | 3°C | 7°C |
| February | 0°C | 3°C | 7°C |
| March | 0°C | 6°C | 12°C |
| April | 4°C | 9°C | 15°C |
| May | 8°C | 14°C | 21°C |
| June | 15°C | 19°C | 23°C |
| July | 21°C | 25°C | 30°C |
| August | 21°C | 25°C | 30°C |
| September | 17°C | 21°C | 26°C |
| October | 9°C | 14°C | 19°C |
| November | 6°C | 10°C | 14°C |
| December | 3°C | 5°C | 7°C |
Grayrocks Reservoir: Water Temperature by Location
Grayrocks Reservoir: Weather Forecast
October 13
October 14
October 15
October 16
October 17
October 18
Location & Local Information
Grayrocks Reservoir typically runs cold for much of the year owing to its high‑plain location and snowmelt-fed inflows. In spring (April–May) surface temperatures commonly range from roughly 35–55°F (2–13°C) as snowmelt and cool weather keep the water chillier. Summer months (June–August) bring the warmest conditions, with surface readings frequently between about 60–75°F (15–24°C) and occasionally topping the high 70s °F (around 24–26°C) in warm, calm spells. By early fall (September–October) temperatures usually drop back into the 50s–60s °F (10–18°C), and in winter the reservoir often sits at or near freezing, with ice forming on the surface when conditions are sustained below 32°F (0°C).
Swimming at Grayrocks Reservoir is generally allowed as part of its recreational use, but it is not structured like a staffed beach and conditions can make swimming risky. Cold water, sudden temperature stratification, steep drop‑offs, fluctuating water levels for irrigation, boat traffic, and the absence of lifeguards mean swimmers should exercise caution, use flotation, and be mindful of posted rules or temporary advisories. Many visitors choose to swim during the warmest weeks of summer, but even then water can feel cool compared with low‑elevation lakes.