South Yarmouth water temp
This data the coastal South Yarmouth sea water temperature today, tomorrow and the upcoming days. Besides, you can also get information about the weather and surf forecast, as well as the data on sunrise / sunset and moonrise / moonset at a given point on any given day.
Current sea temperature in South Yarmouth
Water temperature in South Yarmouth today is 68.2°F. Based on our historical data over a period of ten years, the warmest water in this day in the Atlantic Ocean near South Yarmouth was recorded in 2021 and was 71.1°F, and the coldest was recorded in 2008 at 62.6°F. Sea water temperature in South Yarmouth is expected to drop to 63°F in the next 10 days. September average water temperature in South Yarmouth is 67.8°F, the minimum temperature is 61.3°F, and the maximum is 76.3°F.
The swimming season in South Yarmouth lasts from July to September. During those months, South Yarmouth water temperature does not drop below 68°F and therefore suitable for comfortable swimming. The average water temperature in South Yarmouth in winter reaches 40.1°F, in spring 45.7°F, in summer the average temperature rises to 68.4°F, and in autumn it is 59.9°F.
South Yarmouth water temperature now
| September 25, 2025 |
|---|
| today temp |
| 68.2°F |
| September 24, 2025 |
|---|
| yesterday temp |
| 68°F |
The sea salinity in South Yarmouth is 31.85‰, and the average salinity of the World Ocean is 35‰.
Surf Forecast in South Yarmouth for today
Another important indicators for a comfortable holiday on the beach are the presence and height of the waves, as well as the speed and direction of the wind. Please find below data on the swell size for South Yarmouth. We calculate the swell size based on the mean wave height (trough to crest) of each third highest wave. For more information on surf forecasts for the next ten days, please visit sea state forecast South Yarmouth. Data in table shown for September 25, 2025, time in GMT 0 format (you can change the time zone on the sea state forecast page)
| 0-3 h | 3-6 h | 6-9 h | 9-12 h |
|---|---|---|---|
| 1' 4" | 1' 4" | 1' 3" | 1' 3" |
| 0.41 m | 0.4 m | 0.38 m | 0.39 m |
| 12-15 h | 15-18 h | 18-21 h | 21-24 h |
|---|---|---|---|
| 1' 7" | 1' 9" | 2' 0" | 2' 3" |
| 0.47 m | 0.53 m | 0.62 m | 0.69 m |
Surf report in South Yarmouth
South Yarmouth weather forecast
Current temperature and weather
Data in a table show South Yarmouth temperature today (September 25, 2025). For more information and forecast for a few days, go to the weather forecast South Yarmouth.
| 0-3 h | 3-6 h | 6-9 h | 9-12 h |
|---|---|---|---|
 |  | | |
| 64.4°F | 65.1°F | 66°F | 67.8°F |
| 12-15 h | 15-18 h | 18-21 h | 21-24 h |
|---|---|---|---|
 | | | |
| 69.1°F | 68.5°F | 69.1°F | 69.1°F |
You may also be interested in other sections of our site for South Yarmouth: Sunrise and Sunset, Tides
South Yarmouth water temperature by month
These figures shows the average, minimum and maximum monthly sea temperature in South Yarmouth. In addition to the table values, the graph below displays of changes average surface temperature during the year. Values are calculated based on the data over the past 10 years. Using them, you can check the water temperature in South Yarmouth on any day of this period that interests you. Click on the month link and you will see a table for each day, or alternatively you can view the temperature curve of the month and select 2 different years you want to compare, either in a table or as a curve
| Month | Avr | Min | Max | |
|---|---|---|---|---|
| January | 39.4°F | 32.2°F | 46.8°F | cold |
| Sea water temperature in South Yarmouth in January | ||||
| February | 37°F | 30.4°F | 42.1°F | cold |
| Sea water temperature in South Yarmouth in February | ||||
| March | 39°F | 31.6°F | 46.8°F | cold |
| Sea water temperature in South Yarmouth in March | ||||
| April | 45°F | 36.5°F | 52.3°F | cold |
| Sea water temperature in South Yarmouth in April | ||||
| May | 53.2°F | 45.5°F | 64.2°F | cold |
| Sea water temperature in South Yarmouth in May | ||||
| June | 62.4°F | 53.6°F | 73.9°F | cold |
| Sea water temperature in South Yarmouth in June | ||||
| July | 70.7°F | 61.3°F | 79.2°F | warm |
| Sea water temperature in South Yarmouth in July | ||||
| August | 72°F | 64.2°F | 80.8°F | warm |
| Sea water temperature in South Yarmouth in August | ||||
| September | 67.8°F | 61.3°F | 76.3°F | cold |
| Sea water temperature in South Yarmouth in September | ||||
| October | 60.3°F | 52.9°F | 68.9°F | cold |
| Sea water temperature in South Yarmouth in October | ||||
| November | 51.4°F | 43.7°F | 60.8°F | cold |
| Sea water temperature in South Yarmouth in November | ||||
| December | 44.1°F | 36.7°F | 50.9°F | cold |
| Sea water temperature in South Yarmouth in December | ||||
Chart monthly average water temperature in South Yarmouth
