This data the coastal Mastic Beach ocean 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.
Water temperature in Mastic Beach today is 70°F. Based on our historical data over a period of ten years, the warmest water in this day in the Atlantic Ocean near Mastic Beach was recorded in 2018 and was 75°F, and the coldest was recorded in 2017 at 68°F. Sea water temperature in Mastic Beach is expected to rise to 70.2°F in the next 10 days. September average water temperature in Mastic Beach is 69.6°F, the minimum temperature is 64.4°F, and the maximum is 75.2°F.
The swimming season in Mastic Beach lasts from July to September. During those months, Mastic Beach water temperature does not drop below 68°F and therefore suitable for comfortable swimming. The average water temperature in Mastic Beach in winter reaches 44.2°F, in spring 46.4°F, in summer the average temperature rises to 69.3°F, and in autumn it is 63.3°F.
September 5, 2025 |
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today temp |
70°F |
September 4, 2025 |
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yesterday temp |
69.4°F |
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 Mastic Beach. 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 Mastic Beach. Data in table shown for September 5, 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 |
---|---|---|---|
3' 8" | 3' 8" | 3' 10" | 3' 10" |
1.13 m | 1.13 m | 1.16 m | 1.16 m |
12-15 h | 15-18 h | 18-21 h | 21-24 h |
---|---|---|---|
3' 9" | 3' 10" | 4' 6" | 4' 11" |
1.15 m | 1.17 m | 1.37 m | 1.5 m |
Data in a table show Mastic Beach temperature today (September 5, 2025). For more information and forecast for a few days, go to the weather forecast Mastic Beach.
0-3 h | 3-6 h | 6-9 h | 9-12 h |
---|---|---|---|
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68.5°F | 68.5°F | 69.3°F | 72°F |
12-15 h | 15-18 h | 18-21 h | 21-24 h |
---|---|---|---|
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76.3°F | 76.6°F | 72.9°F | 71.4°F |
You may also be interested in other sections of our site for Mastic Beach: Sunrise and Sunset, Tides
These figures shows the average, minimum and maximum monthly sea temperature in Mastic Beach. 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 Mastic Beach 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 | |
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January | 43.3°F | 37.8°F | 50.9°F | cold |
Ocean water temperature in Mastic Beach in January | ||||
February | 40.1°F | 35.1°F | 45.1°F | cold |
Ocean water temperature in Mastic Beach in February | ||||
March | 40.8°F | 35.1°F | 50.4°F | cold |
Ocean water temperature in Mastic Beach in March | ||||
April | 45.3°F | 37.9°F | 53.1°F | cold |
Ocean water temperature in Mastic Beach in April | ||||
May | 53.1°F | 45.9°F | 65.1°F | cold |
Ocean water temperature in Mastic Beach in May | ||||
June | 63.1°F | 55.2°F | 72°F | cold |
Ocean water temperature in Mastic Beach in June | ||||
July | 71.8°F | 64.9°F | 77.2°F | warm |
Ocean water temperature in Mastic Beach in July | ||||
August | 72.9°F | 68°F | 76.8°F | warm |
Ocean water temperature in Mastic Beach in August | ||||
September | 69.6°F | 64.4°F | 75.2°F | warm |
Ocean water temperature in Mastic Beach in September | ||||
October | 63.9°F | 57.4°F | 70.2°F | cold |
Ocean water temperature in Mastic Beach in October | ||||
November | 56.5°F | 50°F | 63.1°F | cold |
Ocean water temperature in Mastic Beach in November | ||||
December | 49.1°F | 42.3°F | 55.6°F | cold |
Ocean water temperature in Mastic Beach in December |