Quabbin Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Quabbin Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Quabbin Reservoir today is 21.5°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 |
|---|---|---|---|
| JUN 23 | 21.6°C | 17.6°C | |
| JUN 24 | 21.6°C | 17.6°C | |
| JUN 25 | 21.7°C | 17.6°C | |
| JUN 26 | 21.6°C | 17.6°C | |
| JUN 27 | 21.8°C | 17.6°C | |
| JUN 28 | 21.9°C | 17.6°C | |
| JUN 29 | 21.0°C | 17.6°C | |
| JUN 30 | 21.0°C | 17.6°C | |
| JUL 1 | 23.0°C | 21.6°C | |
| JUL 2 | 23.0°C | 21.7°C | |
| JUL 3 | 23.0°C | 21.7°C | |
| JUL 4 | 23.0°C | 21.8°C | |
| JUL 5 | 23.0°C | 21.9°C | |
| JUL 6 | 23.0°C | 22.0°C | |
| JUL 7 | 23.0°C | 22.0°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 | 4°C | 6°C |
| March | 2°C | 4°C | 7°C |
| April | 3°C | 8°C | 12°C |
| May | 7°C | 13°C | 19°C |
| June | 13°C | 18°C | 23°C |
| July | 20°C | 23°C | 26°C |
| August | 20°C | 23°C | 26°C |
| September | 19°C | 22°C | 24°C |
| October | 11°C | 15°C | 19°C |
| November | 4°C | 9°C | 12°C |
| December | 1°C | 4°C | 6°C |
Quabbin Reservoir: Water Temperature by Location
Quabbin Reservoir: Weather Forecast
July 1
July 2
July 3
July 4
July 5
July 6
Location & Local Information
Quabbin Reservoir, the large engineered lake in central Massachusetts that supplies drinking water to the Boston area, shows pronounced seasonal and vertical temperature variation. In winter the surface commonly hovers near freezing, about 32–40°F (0–4°C), and the reservoir often forms ice where conditions allow. Spring brings a gradual warm-up to roughly 35–55°F (2–13°C) as the surface mixes and stratification begins. During summer the epilimnion can reach about 60–75°F (16–24°C) on warm days, while deeper layers remain much colder—often around 39°F (4°C) or lower—because the reservoir is deep and thermally stratified. In autumn the surface cools again into the mid‑40s to low‑60s°F (7–16°C) before full turnover.
Swimming in Quabbin Reservoir is not permitted. The reservoir is managed primarily as a protected public water supply, and recreational swimming is banned to minimize contamination risks and to maintain water quality and security for downstream users. There are also safety concerns: cold water temperatures, sudden depth changes, and underwater hazards increase the danger of cold-water shock and drowning. While the surrounding public lands allow hiking, fishing in designated areas, and observation, direct contact activities such as swimming are prohibited for both environmental protection and public-safety reasons.