Allegheny Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Allegheny Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Allegheny Reservoir today is 21°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 |
|---|---|---|---|
| AUG 25 | 20.8°C | 24.0°C | |
| AUG 26 | 20.2°C | 24.0°C | |
| AUG 27 | 20.1°C | 24.0°C | |
| AUG 28 | 20.8°C | 24.0°C | |
| AUG 29 | 21.0°C | 24.0°C | |
| AUG 30 | 21.0°C | 24.0°C | |
| AUG 31 | 20.9°C | 24.0°C | |
| SEP 1 | 21.0°C | 21.5°C | |
| SEP 2 | 21.5°C | 21.0°C | |
| SEP 3 | 21.5°C | 21.1°C | |
| SEP 4 | 21.5°C | 21.1°C | |
| SEP 5 | 21.5°C | 21.1°C | |
| SEP 6 | 21.5°C | 21.1°C | |
| SEP 7 | 21.5°C | 21.2°C | |
| SEP 8 | 21.5°C | 21.2°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 | 0°C | 3°C | 6°C |
| February | 0°C | 4°C | 7°C |
| March | 0°C | 4°C | 7°C |
| April | 4°C | 10°C | 14°C |
| May | 9°C | 16°C | 22°C |
| June | 14°C | 19°C | 24°C |
| July | 20°C | 24°C | 27°C |
| August | 19°C | 24°C | 29°C |
| September | 18°C | 22°C | 25°C |
| October | 13°C | 16°C | 18°C |
| November | 4°C | 9°C | 13°C |
| December | 1°C | 5°C | 8°C |
Allegheny Reservoir: Water Temperature by Location
Allegheny Reservoir: Weather Forecast
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Location & Local Information
The Allegheny Reservoir, a large impoundment on the Allegheny River along the New York–Pennsylvania border, experiences a wide range of surface water temperatures through the year. In winter months the surface commonly approaches freezing, roughly 33–40°F (0–4°C). Spring brings a steady climb as snowmelt and warming air drive temperatures into the 40–60°F range (4–16°C). By summer the upper layers of the reservoir often warm to about 65–78°F (18–26°C) on warm, calm days, though nights and deeper water remain cooler. In autumn surface temperatures typically fall back into the 50–65°F band (10–18°C) as air temperatures drop and stratification breaks down.
Swimming is generally allowed in parts of the Allegheny Reservoir, particularly at developed recreation sites and designated beach or day-use areas managed by the reservoir’s authorities, because the impoundment is intended for multiple recreational uses. However, access and activities are subject to posted regulations: some shorelines are private or restricted, lifeguards may not be provided, and hazards such as cold pockets, sudden drop-offs, submerged structures, and boat traffic can pose risks. Seasonal water temperatures and local management decisions also influence whether swimming is recommended or limited at specific locations.
