Long Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Long Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Long Lake today is 18.4°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 |
|---|---|---|---|
| JUN 3 | 12.1°C | 14.2°C | |
| JUN 4 | 12.6°C | 14.2°C | |
| JUN 5 | 12.9°C | 14.2°C | |
| JUN 6 | 14.2°C | 14.2°C | |
| JUN 7 | 17.4°C | 14.2°C | |
| JUN 8 | 17.6°C | 14.2°C | |
| JUN 10 | 18.0°C | 14.2°C | |
| JUN 11 | 14.2°C | 18.2°C | |
| JUN 12 | 14.2°C | 18.0°C | |
| JUN 13 | 14.2°C | 17.8°C | |
| JUN 14 | 14.2°C | 17.6°C | |
| JUN 15 | 14.2°C | 17.4°C | |
| JUN 16 | 14.2°C | 17.1°C | |
| JUN 17 | 14.2°C | 16.9°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 | 1°C | 4°C | 6°C |
| February | 2°C | 4°C | 7°C |
| March | 1°C | 4°C | 7°C |
| April | 1°C | 4°C | 8°C |
| May | 5°C | 10°C | 16°C |
| June | 10°C | 14°C | 19°C |
| July | 13°C | 17°C | 21°C |
| August | 16°C | 20°C | 23°C |
| September | 15°C | 19°C | 22°C |
| October | 10°C | 15°C | 19°C |
| November | 5°C | 10°C | 14°C |
| December | 1°C | 4°C | 8°C |
Long Lake: Water Temperature by Location
Long Lake: Weather Forecast
June 9
June 10
June 11
June 12
June 13
Location & Local Information
Long Lake in Maine experiences a wide range of water temperatures through the year because of its northern climate and seasonal stratification. In late spring (May–June) surface temperatures typically rise from about 45–60°F (7–16°C) as ice-out gives way to warming; in midsummer (July–August) the surface commonly reaches roughly 68–75°F (20–24°C) at the warmest and can be slightly warmer in shallow bays and nearshore shallows. By early fall (September–October) surface temperatures usually cool back into the 60s°F (about 16–20°C). During winter, when the lake is ice-covered, the water just beneath the ice will be near freezing up to around 34–39°F (0–4°C) while deeper layers remain a few degrees warmer.
Swimming in Long Lake is permitted and commonly practiced in summer at public beaches and accessible shorelines because surface temperatures during July and August are comfortable for most swimmers. Conditions vary by location on the lake, wind, and recent weather, so swimmers should prefer designated swimming areas, heed any local advisories about water quality or algal blooms, and be mindful of cold-water risks outside peak summer months. Cold, deep water and boat traffic also make cautious practices—such as not swimming alone and wearing a life jacket when boating—important year-round.