Lake Sebago — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lake Sebago, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lake Sebago today is 79°F.
Water Temperature: Daily Trends, Historical Records, and Forecast
✅ As of today, the minimum water temperature ranges from 79°F (26°C) to 82°F (28°C). This is very warm water, allowing for extended stays without any discomfort. Swimming in these conditions will be particularly enjoyable, making it the ideal temperature range for those who want to relax in the sea. Additionally, water in this temperature range is suitable for children and elderly people, as it is comfortable for prolonged stays. 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 |
|---|---|---|---|
| JUL 11 | 74°F | 78°F | |
| JUL 12 | 74°F | 78°F | |
| JUL 13 | 74°F | 78°F | |
| JUL 14 | 75°F | 78°F | |
| JUL 15 | 79°F | 78°F | |
| JUL 16 | 79°F | 78°F | |
| JUL 17 | 79°F | 78°F | |
| JUL 18 | 79°F | 78°F | |
| JUL 19 | 78°F | 79°F | |
| JUL 20 | 78°F | 79°F | |
| JUL 21 | 78°F | 79°F | |
| JUL 22 | 78°F | 79°F | |
| JUL 23 | 78°F | 79°F | |
| JUL 24 | 78°F | 79°F | |
| JUL 25 | 78°F | 79°F |
* 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 | 32°F | 36°F | 41°F |
| February | 32°F | 34°F | 39°F |
| March | 32°F | 38°F | 45°F |
| April | 37°F | 48°F | 59°F |
| May | 52°F | 60°F | 70°F |
| June | 63°F | 69°F | 75°F |
| July | 70°F | 78°F | 86°F |
| August | 72°F | 78°F | 84°F |
| September | 68°F | 74°F | 81°F |
| October | 52°F | 60°F | 68°F |
| November | 43°F | 49°F | 54°F |
| December | 32°F | 39°F | 45°F |
Lake Sebago: Water Temperature by Location
Lake Sebago: Weather Forecast
July 19
July 20
July 21
July 22
July 23
Location & Local Information
Lake Sebago, a man-made lake in Harriman State Park, typically shows a wide seasonal swing in surface water temperatures. In winter the surface often approaches freezing, roughly 32–40°F (0–4°C) and can ice over on cold stretches. During spring the water gradually warms into the mid-40s to low-60s °F (about 7–16°C) as air temperatures rise and runoff mixes in. Summer brings the warmest conditions: surface readings commonly range from the low to mid 70s °F (around 21–25°C) and on hot, calm days can edge into the upper 70s °F (about 25–26°C). In fall the lake cools again, often sitting in the 50s to low 60s °F (10–16°C) as nights turn colder.
Swimming is allowed in Lake Sebago but generally only in designated beach areas during the park’s official swimming season and subject to state park rules and posted advisories. The park may staff lifeguards at busy times, but visitors should check current conditions before entering the water since temporary closures can occur for water‑quality concerns, algal blooms, or safety issues. The lake’s relatively shallow, sunlit edges warm in summer and are most comfortable for swimming, while spring and fall waters can feel brisk and winter immersion is unsafe without specialized equipment and training.