Big Sage Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Big Sage Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Big Sage Reservoir today is 18.2°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 |
|---|---|---|---|
| JUN 3 | 17.6°C | 21.4°C | |
| JUN 4 | 18.5°C | 21.4°C | |
| JUN 5 | 18.5°C | 21.4°C | |
| JUN 6 | 18.5°C | 21.4°C | |
| JUN 7 | 19.5°C | 21.4°C | |
| JUN 8 | 19.3°C | 21.4°C | |
| JUN 10 | 18.2°C | 21.4°C | |
| JUN 11 | 21.4°C | 18.4°C | |
| JUN 12 | 21.4°C | 18.5°C | |
| JUN 13 | 21.4°C | 18.7°C | |
| JUN 14 | 21.4°C | 18.8°C | |
| JUN 15 | 21.4°C | 19.0°C | |
| JUN 16 | 21.4°C | 19.2°C | |
| JUN 17 | 21.4°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 | 0°C | 2°C | 5°C |
| February | 1°C | 3°C | 6°C |
| March | 2°C | 5°C | 8°C |
| April | 4°C | 8°C | 11°C |
| May | 10°C | 16°C | 20°C |
| June | 17°C | 21°C | 25°C |
| July | 19°C | 22°C | 25°C |
| August | 22°C | 24°C | 27°C |
| September | 18°C | 21°C | 24°C |
| October | 10°C | 14°C | 18°C |
| November | 3°C | 7°C | 10°C |
| December | 0°C | 2°C | 4°C |
Big Sage Reservoir: Water Temperature by Location
Big Sage Reservoir: Weather Forecast
June 9
June 10
June 11
June 12
June 13
Location & Local Information
Big Sage Reservoir’s surface water temperatures change a lot through the year. In winter the lake commonly chills into the 40s–50°F (4–10°C), often cold enough to discourage extended immersion. Spring and fall tend to bring moderate surface readings around 50–65°F (10–18°C) as runoff and air temperatures shift. In the warmest weeks of summer the surface can warm to roughly 60–75°F (16–24°C), though this depends on weather, shading and elevation; deeper water remains substantially cooler year‑round, often staying in the 40s–50s°F (4–12°C) below the thermocline.
Swimming at Big Sage Reservoir is generally possible where public access is allowed, but conditions and rules vary so it’s important to check local signage and landowner restrictions before entering the water. Cold temperatures, sudden drop‑offs and the absence of lifeguards make unguarded swimming potentially hazardous, and boat traffic or occasional algal blooms can further limit safe areas. Because water may be used for irrigation or other purposes, some shores or coves can be off limits. Visitors should assess water clarity and temperature, wear a life jacket if boating, and avoid prolonged immersion in cold water to reduce the risk of cold‑water shock and hypothermia.