Lake Winnisquam — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lake Winnisquam, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lake Winnisquam today is 19.7°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 |
|---|---|---|---|
| SEP 16 | 21.0°C | 21.0°C | |
| SEP 17 | 20.0°C | 21.0°C | |
| SEP 18 | 20.4°C | 21.0°C | |
| SEP 19 | 21.0°C | 21.0°C | |
| SEP 20 | 20.9°C | 21.0°C | |
| SEP 21 | 20.0°C | 21.0°C | |
| SEP 22 | 19.7°C | 21.0°C | |
| SEP 23 | 19.7°C | 21.0°C | |
| SEP 24 | 21.0°C | 19.8°C | |
| SEP 25 | 21.0°C | 19.8°C | |
| SEP 26 | 21.0°C | 19.9°C | |
| SEP 27 | 21.0°C | 20.0°C | |
| SEP 28 | 21.0°C | 20.0°C | |
| SEP 29 | 21.0°C | 20.1°C | |
| SEP 30 | 21.0°C | 20.2°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 | 8°C | 15°C |
| February | 0°C | 7°C | 13°C |
| March | 0°C | 7°C | 13°C |
| April | 1°C | 9°C | 16°C |
| May | 9°C | 14°C | 19°C |
| June | 14°C | 18°C | 22°C |
| July | 20°C | 26°C | 31°C |
| August | 21°C | 23°C | 26°C |
| September | 18°C | 21°C | 24°C |
| October | 11°C | 15°C | 19°C |
| November | 4°C | 8°C | 11°C |
| December | 1°C | 5°C | 7°C |
Lake Winnisquam: Water Temperature by Location
Lake Winnisquam: Weather Forecast
September 23
September 24
September 25
September 26
September 27
Location & Local Information
Lake Winnisquam’s surface water temperatures vary widely through the year and with depth. In spring, as ice melts and runoff cools the basin, surface temperatures commonly sit around 40–60°F (4–16°C). Summer brings the warmest conditions, with typical surface readings in late June through August of about 68–78°F (20–26°C), and on hot, calm days shallow bays can climb toward 80°F (27°C). By early fall the surface cools into the 50s–60s°F (10–18°C) range before winter returns the lake to near-freezing conditions around 32°F (0°C) and often solid ice cover. Deeper water remains significantly colder year-round; thermal stratification in summer means bottom temperatures can stay in the 40s–50s°F (4–12°C), so actual exposure depends on where you swim.
Swimming is generally allowed at Lake Winnisquam because it is a public recreational lake with beaches, boat launches and private shorelines used for bathing and cooling off. Local authorities and landowners set access rules, and seasonal beach openings or posted advisories may restrict swimming for safety or water-quality reasons. Swimmers should be mindful of cold-water shock in early and late season, variable depths, boat traffic, and occasional algal-bloom or contamination advisories that can temporarily close areas to bathing.