Sag Harbor water temp
This data the coastal Sag Harbor 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 Sag Harbor
Water temperature in Sag Harbor today is 70.5°F. Based on our historical data over a period of ten years, the warmest water in this day in Sag Harbor was recorded in 2018 and was 75.2°F, and the coldest was recorded in 2017 at 68.2°F. Sea water temperature in Sag Harbor is expected to drop to 70.2°F in the next 10 days. September average water temperature in Sag Harbor is 69.6°F, the minimum temperature is 64.8°F, and the maximum is 75.7°F.
The swimming season in Sag Harbor lasts from July to September. During those months, Sag Harbor water temperature does not drop below 68°F and therefore suitable for comfortable swimming. The average water temperature in Sag Harbor in winter reaches 42.8°F, in spring 46.2°F, in summer the average temperature rises to 69.1°F, and in autumn it is 62.8°F.
Sag Harbor water temperature now
| September 5, 2025 |
|---|
| today temp |
| 70.5°F |
| September 4, 2025 |
|---|
| yesterday temp |
| 69.6°F |
The sea salinity in Sag Harbor is 27.06‰, and the average salinity of the World Ocean is 35‰.
Surf Forecast in Sag Harbor 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 Sag Harbor. 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 Sag Harbor. Data in table shown for September 6, 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' 5" | 1' 4" | 1' 5" | 1' 4" |
| 0.42 m | 0.41 m | 0.42 m | 0.4 m |
| 12-15 h | 15-18 h | 18-21 h | 21-24 h |
|---|---|---|---|
| 1' 7" | 1' 11" | 2' 2" | 2' 3" |
| 0.48 m | 0.59 m | 0.66 m | 0.68 m |
Surf report in Sag Harbor
Sag Harbor weather forecast
Current temperature and weather
Data in a table show Sag Harbor temperature today (September 6, 2025). For more information and forecast for a few days, go to the weather forecast Sag Harbor.
| 0-3 h | 3-6 h | 6-9 h | 9-12 h |
|---|---|---|---|
 |  | | |
| 67.3°F | 68.5°F | 69.1°F | 70.3°F |
| 12-15 h | 15-18 h | 18-21 h | 21-24 h |
|---|---|---|---|
 |  | | |
| 72.7°F | 72.9°F | 71.1°F | 70.5°F |
You may also be interested in other sections of our site for Sag Harbor: Sunrise and Sunset, Tides
Sag Harbor water temperature by month
These figures shows the average, minimum and maximum monthly sea temperature in Sag Harbor. 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 Sag Harbor 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 | 41.9°F | 35.2°F | 48.6°F | cold |
| Sea water temperature in Sag Harbor in January | ||||
| February | 38.7°F | 32.9°F | 43.9°F | cold |
| Sea water temperature in Sag Harbor in February | ||||
| March | 40.1°F | 33.3°F | 49.8°F | cold |
| Sea water temperature in Sag Harbor in March | ||||
| April | 45.3°F | 36.7°F | 52.7°F | cold |
| Sea water temperature in Sag Harbor in April | ||||
| May | 53.1°F | 45.3°F | 63.9°F | cold |
| Sea water temperature in Sag Harbor in May | ||||
| June | 62.8°F | 55.4°F | 71.4°F | cold |
| Sea water temperature in Sag Harbor in June | ||||
| July | 71.4°F | 63.3°F | 78.6°F | warm |
| Sea water temperature in Sag Harbor in July | ||||
| August | 72.9°F | 67.6°F | 78.1°F | warm |
| Sea water temperature in Sag Harbor in August | ||||
| September | 69.6°F | 64.8°F | 75.7°F | warm |
| Sea water temperature in Sag Harbor in September | ||||
| October | 63.3°F | 56.7°F | 68.7°F | cold |
| Sea water temperature in Sag Harbor in October | ||||
| November | 55.4°F | 49.5°F | 62.8°F | cold |
| Sea water temperature in Sag Harbor in November | ||||
| December | 47.8°F | 40.8°F | 53.4°F | cold |
| Sea water temperature in Sag Harbor in December | ||||
Chart monthly average water temperature in Sag Harbor
