San Mateo water temp
This data the coastal San Mateo 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 San Mateo
Water temperature in San Mateo today is 71.1°F. Based on our historical data over a period of ten years, the warmest water in this day in San Mateo was recorded in 2019 and was 70.2°F, and the coldest was recorded in 2010 at 55.8°F. Sea water temperature in San Mateo is expected to drop to 61.2°F in the next 10 days. September average water temperature in San Mateo is 62.2°F, the minimum temperature is 55.6°F, and the maximum is 74.1°F.
The swimming season in San Mateo lasts from July to September. During those months, San Mateo water temperature does not drop below 68°F and therefore suitable for comfortable swimming. The average water temperature in San Mateo in winter reaches 53.4°F, in spring 56.3°F, in summer the average temperature rises to 61.2°F, and in autumn it is 60.3°F.
San Mateo water temperature now
| September 27, 2025 |
|---|
| today temp |
| 71.1°F |
| September 26, 2025 |
|---|
| yesterday temp |
| 70.7°F |
The ocean salinity in San Mateo is 11.21‰, and the average salinity of the World Ocean is 35‰.
Surf Forecast in San Mateo 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 San Mateo. 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 San Mateo. Data in table shown for September 27, 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 |
|---|---|---|---|
| 2' 7" | 2' 7" | 2' 7" | 2' 7" |
| 0.78 m | 0.79 m | 0.79 m | 0.79 m |
| 12-15 h | 15-18 h | 18-21 h | 21-24 h |
|---|---|---|---|
| 2' 7" | 2' 6" | 2' 6" | 2' 7" |
| 0.78 m | 0.76 m | 0.76 m | 0.78 m |
Surf report in San Mateo
San Mateo weather forecast
Current temperature and weather
Data in a table show San Mateo temperature today (September 27, 2025). For more information and forecast for a few days, go to the weather forecast San Mateo.
| 0-3 h | 3-6 h | 6-9 h | 9-12 h |
|---|---|---|---|
 | | |  |
| 60.6°F | 59.2°F | 57.6°F | 65.3°F |
| 12-15 h | 15-18 h | 18-21 h | 21-24 h |
|---|---|---|---|
 | | |  |
| 69.6°F | 70.9°F | 65.3°F | 61.5°F |
You may also be interested in other sections of our site for San Mateo: Sunrise and Sunset, Tides
San Mateo water temperature by month
These figures shows the average, minimum and maximum monthly sea temperature in San Mateo. 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 San Mateo 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 | 50.2°F | 55.8°F | cold |
| Ocean water temperature in San Mateo in January | ||||
| February | 53.4°F | 50.4°F | 59.4°F | cold |
| Ocean water temperature in San Mateo in February | ||||
| March | 55.2°F | 49.3°F | 59.9°F | cold |
| Ocean water temperature in San Mateo in March | ||||
| April | 56.5°F | 50.7°F | 65.1°F | cold |
| Ocean water temperature in San Mateo in April | ||||
| May | 57.4°F | 49.8°F | 69.3°F | cold |
| Ocean water temperature in San Mateo in May | ||||
| June | 59.7°F | 51.6°F | 72.5°F | cold |
| Ocean water temperature in San Mateo in June | ||||
| July | 61.7°F | 52.9°F | 73.9°F | cold |
| Ocean water temperature in San Mateo in July | ||||
| August | 62.2°F | 54.1°F | 74.7°F | cold |
| Ocean water temperature in San Mateo in August | ||||
| September | 62.2°F | 55.6°F | 74.1°F | cold |
| Ocean water temperature in San Mateo in September | ||||
| October | 60.6°F | 54.1°F | 71.6°F | cold |
| Ocean water temperature in San Mateo in October | ||||
| November | 57.7°F | 52.7°F | 64.2°F | cold |
| Ocean water temperature in San Mateo in November | ||||
| December | 54.1°F | 50.9°F | 59.2°F | cold |
| Ocean water temperature in San Mateo in December | ||||
Chart monthly average water temperature in San Mateo
