South Portland Water Temperature

(Today) 2025

13.9°C / 57.1°F

The water will feel cool (fresh). Probably too cold for all but seasoned swimmers. We'd recommend a 4mm or 5mm wetsuit if you want to stay in the water.

*Live data from Portland, ME: 13.9°C / 57°F

Current weather

18°C / 65°F
(clear sky)
Partly cloudy
Wind
7 mph
Humidity
74%

The measurements for the water temperature in South Portland, Maine are provided by the daily satellite readings provided by the NOAA. The temperatures given are the sea surface temperature (SST) which is most relevant to recreational users.

*Live data may vary from satellite readings for a number of reasons. These include local factors, depth of smapling and time of day.

Water temp by month

Monthly average max / min water temperatures

The graph below shows the range of monthly South Portland water temperature derived from many years of historical sea surface temperature data.

South Portland average maximum / minimum water temperatures
Maximum and minimum monthly sea temperatures in South Portland
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Min °C 3.3 2.2 1.8 3.3 5 9.8 14.3 16.3 14 9.7 8 5.2
Max °C 6.5 5.1 4.7 7 10.7 15.4 19 19.4 18.2 15.9 11.2 9.3
Min °F 39.2 37.1 36.4 39.4 43.2 51.9 59.6 62.5 58.9 51.9 47.7 43
Max °F 42.4 40 39.3 43.1 48.9 57.5 64.3 65.6 63.1 58.1 50.9 47.1

The warmest water temperature is in August with an average around 64°F / 17.8°C. The coldest month is March with an average water temperature of 37.8°F / 3.2°C.