Rimrock Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Rimrock Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Rimrock Lake today is 19.2°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 |
|---|---|---|---|
| JUL 14 | 16.7°C | 22.6°C | |
| JUL 15 | 18.4°C | 22.6°C | |
| JUL 16 | 18.4°C | 22.6°C | |
| JUL 17 | 18.4°C | 22.6°C | |
| JUL 18 | 18.5°C | 22.6°C | |
| JUL 19 | 18.5°C | 22.6°C | |
| JUL 20 | 18.6°C | 22.6°C | |
| JUL 21 | 18.7°C | 22.6°C | |
| JUL 22 | 22.6°C | 19.4°C | |
| JUL 23 | 22.6°C | 19.5°C | |
| JUL 24 | 22.6°C | 19.7°C | |
| JUL 25 | 22.6°C | 19.9°C | |
| JUL 26 | 22.6°C | 20.1°C | |
| JUL 27 | 22.6°C | 20.2°C | |
| JUL 28 | 22.6°C | 20.4°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 | 4°C |
| February | 0°C | 4°C | 8°C |
| March | 1°C | 6°C | 11°C |
| April | 2°C | 9°C | 15°C |
| May | 7°C | 14°C | 21°C |
| June | 10°C | 18°C | 24°C |
| July | 14°C | 23°C | 31°C |
| August | 15°C | 23°C | 30°C |
| September | 16°C | 21°C | 26°C |
| October | 9°C | 15°C | 20°C |
| November | 3°C | 9°C | 14°C |
| December | 1°C | 5°C | 9°C |
Rimrock Lake: Water Temperature by Location
Rimrock Lake: Weather Forecast
July 22
July 23
July 24
July 25
July 26
Location & Local Information
Rimrock Lake, a reservoir in central Washington, tends to run cool for much of the year because of its mountain setting and depth. Surface temperatures typically range from about 32–40°F (0–4°C) in winter when ice or near‑freezing conditions are possible, 40–55°F (4–13°C) in spring as snowmelt feeds the lake, and roughly 60–72°F (15–22°C) in the warmest weeks of summer. In autumn the surface usually drops back into the 50–60°F (10–16°C) band. Deeper water stays markedly colder year‑round, so overall thermal stratification and sudden cold pulls can occur even on warm days.
Swimming is generally permitted because Rimrock Lake is managed as a multi‑use recreation area that allows boating, fishing and shore activities; there are no widespread prohibitions against entering the water. However, conditions make swimming more challenging and sometimes risky: the water can be uncomfortably cold outside mid‑summer, there are few lifeguards or designated swim beaches, boat traffic and steep drop‑offs can present hazards, and hypothermia can set in quickly in chilly temperatures. Visitors should check local signage, choose protected shallow spots if available, wear a life jacket when appropriate, and avoid long exposures in cold water.