Prettyboy Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Prettyboy Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Prettyboy Reservoir today is 18.5°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 |
|---|---|---|---|
| OCT 5 | 20.9°C | 20.5°C | |
| OCT 6 | 19.9°C | 20.5°C | |
| OCT 7 | 19.7°C | 20.5°C | |
| OCT 8 | 19.6°C | 20.5°C | |
| OCT 9 | 19.0°C | 20.5°C | |
| OCT 10 | 18.4°C | 20.5°C | |
| OCT 11 | 18.6°C | 20.5°C | |
| OCT 12 | 18.4°C | 20.5°C | |
| OCT 13 | 20.5°C | 18.6°C | |
| OCT 14 | 20.5°C | 18.7°C | |
| OCT 15 | 20.5°C | 18.8°C | |
| OCT 16 | 20.5°C | 18.9°C | |
| OCT 17 | 20.5°C | 19.0°C | |
| OCT 18 | 20.5°C | 19.1°C | |
| OCT 19 | 20.5°C | 19.2°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 | 4°C | 7°C |
| February | 1°C | 4°C | 7°C |
| March | 1°C | 5°C | 10°C |
| April | 7°C | 12°C | 17°C |
| May | 13°C | 18°C | 24°C |
| June | 17°C | 20°C | 24°C |
| July | 19°C | 24°C | 29°C |
| August | 21°C | 23°C | 26°C |
| September | 21°C | 24°C | 26°C |
| October | 17°C | 21°C | 24°C |
| November | 8°C | 13°C | 17°C |
| December | 4°C | 7°C | 10°C |
Prettyboy Reservoir: Water Temperature by Location
Prettyboy Reservoir: Weather Forecast
October 13
October 14
October 15
October 16
October 17
October 18
Location & Local Information
Prettyboy Reservoir, a drinking-water impoundment in Maryland, tends to run cooler than many shallow recreational lakes. Seasonal surface temperatures typically range from roughly 34–40°F (1–4°C) in winter, rise to about 45–65°F (7–18°C) through spring, peak in midsummer near 70–82°F (21–28°C) depending on air temperatures and depth, and then cool back to roughly 50–70°F (10–21°C) in autumn. Local conditions, recent weather, and depth can change these numbers day to day; deeper, shaded areas will remain colder than shallow, sunlit spots. Even in summer months the reservoir can have sudden cold layers or thermoclines that affect how warm the surface feels.
Public swimming is not permitted at Prettyboy Reservoir. The prohibition reflects its role as a municipal water supply and the need to protect source-water quality, as well as safety concerns—cold water, steep banks, submerged hazards, and limited shoreline access increase drowning risk. Recreation is generally limited to authorized boating or fishing under the management rules for the watershed, but entering the water for swimming is restricted to prevent contamination and to comply with reservoir regulations designed to keep the supply safe for downstream users.