Eureka water temp
This data the coastal Eureka 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 Eureka
Water temperature in Eureka today is 56.5°F. Based on our historical data over a period of ten years, the warmest water in this day in Eureka was recorded in 2013 and was 60.4°F, and the coldest was recorded in 2008 at 51.6°F. Sea water temperature in Eureka is expected to drop to 54.9°F in the next 10 days. September average water temperature in Eureka is 55.2°F, the minimum temperature is 49.1°F, and the maximum is 61.5°F.
Throughout the year, the water temperature in Eureka does not rise above 68°F and therefore is not suitable for comfortable swimming. The average water temperature in Eureka in winter reaches 51.6°F, in spring 50.9°F, in summer the average temperature rises to 53.6°F, and in autumn it is 54.1°F.
Eureka water temperature now
| September 5, 2025 |
|---|
| today temp |
| 56.5°F |
| September 4, 2025 |
|---|
| yesterday temp |
| 56.3°F |
The ocean salinity in Eureka is 33.95‰, and the average salinity of the World Ocean is 35‰.
Surf Forecast in Eureka 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 Eureka. 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 Eureka. 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' 11" | 3' 9" | 3' 7" | 3' 5" |
| 1.2 m | 1.15 m | 1.09 m | 1.03 m |
| 12-15 h | 15-18 h | 18-21 h | 21-24 h |
|---|---|---|---|
| 3' 3" | 3' 1" | 3' 1" | 3' 0" |
| 0.98 m | 0.95 m | 0.93 m | 0.92 m |
Surf report in Eureka
Eureka weather forecast
Current temperature and weather
Data in a table show Eureka temperature today (September 5, 2025). For more information and forecast for a few days, go to the weather forecast Eureka.
| 0-3 h | 3-6 h | 6-9 h | 9-12 h |
|---|---|---|---|
 | |  | |
| 58.3°F | 57.9°F | 57.9°F | 58.6°F |
| 12-15 h | 15-18 h | 18-21 h | 21-24 h |
|---|---|---|---|
| | | |
| 59.5°F | 59.7°F | 59.5°F | 58.8°F |
You may also be interested in other sections of our site for Eureka: Sunrise and Sunset, Tides
Eureka water temperature by month
These figures shows the average, minimum and maximum monthly sea temperature in Eureka. 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 Eureka 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 | 51.4°F | 48.2°F | 55.8°F | cold |
| Ocean water temperature in Eureka in January | ||||
| February | 50.9°F | 47.7°F | 55.2°F | cold |
| Ocean water temperature in Eureka in February | ||||
| March | 50.7°F | 46°F | 54.9°F | cold |
| Ocean water temperature in Eureka in March | ||||
| April | 50.9°F | 46.9°F | 56.3°F | cold |
| Ocean water temperature in Eureka in April | ||||
| May | 51.3°F | 47.5°F | 55.6°F | cold |
| Ocean water temperature in Eureka in May | ||||
| June | 52.3°F | 45.1°F | 58.1°F | cold |
| Ocean water temperature in Eureka in June | ||||
| July | 53.6°F | 44.1°F | 60.4°F | cold |
| Ocean water temperature in Eureka in July | ||||
| August | 55°F | 48.2°F | 61.9°F | cold |
| Ocean water temperature in Eureka in August | ||||
| September | 55.2°F | 49.1°F | 61.5°F | cold |
| Ocean water temperature in Eureka in September | ||||
| October | 53.6°F | 49.1°F | 59.9°F | cold |
| Ocean water temperature in Eureka in October | ||||
| November | 53.4°F | 48.9°F | 58.5°F | cold |
| Ocean water temperature in Eureka in November | ||||
| December | 52.3°F | 48.2°F | 59.4°F | cold |
| Ocean water temperature in Eureka in December | ||||
Chart monthly average water temperature in Eureka
