Lake Winnipesaukee — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lake Winnipesaukee, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lake Winnipesaukee today is 21.2°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 | 19.9°C | 17.1°C | |
| JUN 24 | 20.1°C | 17.1°C | |
| JUN 25 | 20.3°C | 17.1°C | |
| JUN 26 | 20.3°C | 17.1°C | |
| JUN 27 | 20.4°C | 17.1°C | |
| JUN 28 | 20.5°C | 17.1°C | |
| JUN 29 | 20.5°C | 17.1°C | |
| JUN 30 | 20.5°C | 17.1°C | |
| JUL 1 | 25.0°C | 21.4°C | |
| JUL 2 | 25.0°C | 21.6°C | |
| JUL 3 | 25.0°C | 21.8°C | |
| JUL 4 | 25.0°C | 22.0°C | |
| JUL 5 | 25.0°C | 22.2°C | |
| JUL 6 | 25.0°C | 22.3°C | |
| JUL 7 | 25.0°C | 22.5°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 | 2°C | 10°C | 16°C |
| May | 9°C | 14°C | 19°C |
| June | 13°C | 17°C | 22°C |
| July | 19°C | 25°C | 31°C |
| August | 21°C | 23°C | 26°C |
| September | 19°C | 22°C | 24°C |
| October | 12°C | 16°C | 19°C |
| November | 4°C | 8°C | 12°C |
| December | 1°C | 5°C | 7°C |
Lake Winnipesaukee: Water Temperature by Location
Lake Winnipesaukee: Weather Forecast
July 1
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July 4
July 5
July 6
Location & Local Information
Lake Winnipesaukee’s surface temperature varies markedly by season. In summer the lake commonly warms into the high 60s to mid 70s °F (about 20–24 °C) and during hot spells can reach the upper 70s to low 80s °F (25–28 °C) at the surface. Spring and early summer are cooler, with surface readings often in the 40s to 60s °F (4–16 °C) as the water stratifies, while autumn brings a steady decline back through the 50s into the 40s °F (10–4 °C). In winter the lake freezes in many areas and under-ice temperatures gravitate toward the temperature of maximum density near 39 °F (4 °C); surface ice and slushy conditions are at or below 32 °F (0 °C).
Swimming is generally allowed and popular in warmer months because public beaches, parks and private docks provide access and summer temperatures are comfortable for short swims. However, users should be mindful of cold-water risk outside the warmest weeks, heavy boat traffic in busy areas, and occasional water-quality advisories for cyanobacteria or contamination that can prompt temporary closures. Lifeguards are present at some municipal beaches, but swimmers should check local advisories and exercise caution, since deep, cold water and sudden temperature changes raise risks of cold shock and hypothermia.