Foster City water temp
This data the coastal Foster City 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.
Current ocean temperature in Foster City
Water temperature in Foster City today is 70.9°F. Based on our historical data over a period of ten years, the warmest water in this day in Foster City was recorded in 2019 and was 72.3°F, and the coldest was recorded in 2012 at 56.1°F. Sea water temperature in Foster City is expected to drop to 61.3°F in the next 10 days. September average water temperature in Foster City is 62.2°F, the minimum temperature is 55.6°F, and the maximum is 75°F.
The swimming season in Foster City lasts from June to September. During those months, Foster City water temperature does not drop below 68°F and therefore suitable for comfortable swimming. The average water temperature in Foster City in winter reaches 53.4°F, in spring 56.5°F, in summer the average temperature rises to 61.3°F, and in autumn it is 60.3°F.
Foster City water temperature now
| September 26, 2025 |
|---|
| today temp |
| 70.9°F |
| September 25, 2025 |
|---|
| yesterday temp |
| 71.1°F |
The ocean salinity in Foster City is 11.23‰, and the average salinity of the World Ocean is 35‰.
Surf Forecast in Foster City 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 Foster City. 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 Foster City. Data in table shown for September 26, 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' 1" | 1' 0" | 1' 2" | 1' 4" |
| 0.32 m | 0.31 m | 0.35 m | 0.41 m |
| 12-15 h | 15-18 h | 18-21 h | 21-24 h |
|---|---|---|---|
| 1' 5" | 1' 6" | 1' 6" | 1' 6" |
| 0.44 m | 0.46 m | 0.46 m | 0.46 m |
Surf report in Foster City
Foster City weather forecast
Current temperature and weather
Data in a table show Foster City temperature today (September 26, 2025). For more information and forecast for a few days, go to the weather forecast Foster City.
| 0-3 h | 3-6 h | 6-9 h | 9-12 h |
|---|---|---|---|
 |  | |  |
| 59.4°F | 58.5°F | 57.7°F | 62.8°F |
| 12-15 h | 15-18 h | 18-21 h | 21-24 h |
|---|---|---|---|
 | | |  |
| 71.1°F | 71.6°F | 66.9°F | 61.9°F |
You may also be interested in other sections of our site for Foster City: Sunrise and Sunset, Tides
Foster City water temperature by month
These figures shows the average, minimum and maximum monthly sea temperature in Foster City. 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 Foster City 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 | 52.5°F | 50.4°F | 55.8°F | cold |
| Ocean water temperature in Foster City in January | ||||
| February | 53.4°F | 50.4°F | 59.4°F | cold |
| Ocean water temperature in Foster City in February | ||||
| March | 55.2°F | 49.3°F | 60.4°F | cold |
| Ocean water temperature in Foster City in March | ||||
| April | 56.5°F | 50.7°F | 65.5°F | cold |
| Ocean water temperature in Foster City in April | ||||
| May | 57.6°F | 50°F | 69.3°F | cold |
| Ocean water temperature in Foster City in May | ||||
| June | 59.9°F | 51.8°F | 72.7°F | cold |
| Ocean water temperature in Foster City in June | ||||
| July | 61.9°F | 52.9°F | 74.5°F | cold |
| Ocean water temperature in Foster City in July | ||||
| August | 62.2°F | 54.3°F | 75.4°F | cold |
| Ocean water temperature in Foster City in August | ||||
| September | 62.2°F | 55.6°F | 75°F | cold |
| Ocean water temperature in Foster City in September | ||||
| October | 60.6°F | 54.1°F | 72.1°F | cold |
| Ocean water temperature in Foster City in October | ||||
| November | 57.7°F | 52.7°F | 64.6°F | cold |
| Ocean water temperature in Foster City in November | ||||
| December | 54.1°F | 50.9°F | 59.4°F | cold |
| Ocean water temperature in Foster City in December | ||||
Chart monthly average water temperature in Foster City
