South Branch Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in South Branch Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in South Branch Lake today is 17.1°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 60°F (15°C) to 65°F (18°C). The water is comfortable for most people, making it an ideal range for water sports enthusiasts. The temperature does not cause significant discomfort, and swimming will be pleasant for the majority. However, it's important to remember that prolonged exposure to the water can still lead to cooling, so it's essential to monitor the time spent in the water, especially for children or elderly people. 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 14 | 19.2°C | 18.9°C | |
| SEP 15 | 18.1°C | 18.9°C | |
| SEP 16 | 18.0°C | 18.9°C | |
| SEP 17 | 17.5°C | 18.9°C | |
| SEP 18 | 18.0°C | 18.9°C | |
| SEP 19 | 17.5°C | 18.9°C | |
| SEP 20 | 17.7°C | 18.9°C | |
| SEP 21 | 17.1°C | 18.9°C | |
| SEP 22 | 18.9°C | 17.2°C | |
| SEP 23 | 18.9°C | 17.3°C | |
| SEP 24 | 18.9°C | 17.4°C | |
| SEP 25 | 18.9°C | 17.5°C | |
| SEP 26 | 18.9°C | 17.6°C | |
| SEP 27 | 18.9°C | 17.6°C | |
| SEP 28 | 18.9°C | 17.7°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 | 5°C |
| February | 1°C | 3°C | 6°C |
| March | 1°C | 4°C | 6°C |
| April | 2°C | 4°C | 7°C |
| May | 3°C | 8°C | 13°C |
| June | 8°C | 13°C | 18°C |
| July | 10°C | 18°C | 26°C |
| August | 21°C | 24°C | 27°C |
| September | 15°C | 19°C | 23°C |
| October | 9°C | 13°C | 17°C |
| November | 3°C | 7°C | 11°C |
| December | 0°C | 3°C | 6°C |
South Branch Lake: Water Temperature by Location
South Branch Lake: Weather Forecast
September 21
September 22
September 23
September 24
September 25
September 26
Location & Local Information
South Branch Lake in Maine follows the familiar seasonal temperature pattern of northern New England lakes. After ice-out in spring, surface temperatures typically rise from near-freezing conditions around 34–50°F (1–10°C) through late spring. In summer the surface often warms to roughly 65–75°F (18–24°C), though shallow bays can reach the upper 70s°F (mid-20s °C) on hot days. Deeper water remains much cooler year-round; thermally stratified summer conditions commonly leave bottom layers in the 40s–50s°F (4–10°C). By early fall the surface cools back toward about 45–60°F (7–16°C), and winter returns the lake to near 32°F (0°C) with ice cover when conditions allow.
Swimming in South Branch Lake is generally possible where public access or private shoreline permits it, because it is a freshwater body used for recreation. However, whether people should swim depends on season and local conditions: cold spring and fall temperatures raise the risk of cold-water shock and hypothermia, and winter ice makes swimming hazardous unless under supervised, controlled circumstances. Many areas lack lifeguards and water quality can vary, so swimmers are advised to check local advisories, observe posted signs, and take standard safety precautions such as not swimming alone and wearing a life jacket if conditions are uncertain.