What is the current water temperature in Eureka?

Q: What is the current water temperature in Eureka?

As of now, in Eureka, the water temperature is 13.02°F. Swimming in water of this temperature is considered as extremely cold, and there's a substantial risk of hypothermia if exposed for more than a brief duration.

United States > Eureka

Water temperature in Eureka

Detailed information about the current water temperature in Eureka. The trend over the last two weeks, daily averages, and precise forecast of the water temperature changes. Gain a deeper understanding of seasonal dynamics with monthly statistical analyses covering recent years.

55.4

°F

October 10, 11:37

Trend:

decreasing

Yesterday:

56.3°F

Tomorrow:

55.1°F

Sunrise:

07:22

Sunset:

18:44

Day Length:

11 h. 22 min.

Eureka in October

Minimum:

50.5°F

Average:

52.4°F

Maximum:

55.0°F

Sea water temperature in Eureka today

As of now, in Eureka, the water temperature is 55.4°F. Swimming in water of this temperature is considered as extremely cold, and there's a substantial risk of hypothermia if exposed for more than a brief duration. Today's reading is 1.3°F higher than the average recorded on this particular day in recent years. The sea temperature remains approximately unchanged from yesterday. According to the forecast, we expect the temperature to fall a bit.

Recent sea temperature and forecast

Today's water temperature is slightly lower than the average registered over the last two weeks, indicating a slight cooling trend. It is also close to the historical maximum temperature for this date. The maximum temperature recorded for this date was 56.0°F on 2015, while the historical minimum was 51.4°F on 2017.

latest data

last year

The water temperature over the last two weeks displayed soome variability. While the two week average stayed close to the historical average, there were some days when the temperature was close to the maximum recorded over the past years. The forecast for the upcoming week shows a gradual cooling trend. The average temperature is expected to be 54.8°F, the minimum temperature may reach 54.6°F, and the maximum might stay at 55.1°F.

Daily water temperature in Eureka

Date	Current Year actual* / forecast**	last year	10 years average
Sep 26	54.6°F	54.4°F	55.4°F
Sep 27	55.9°F	54.8°F	55.7°F
Sep 28	55.8°F	53.7°F	55.5°F
Sep 29	55.8°F	51.4°F	55.1°F
Sep 30	55.0°F	53.3°F	55.2°F
Oct 1	54.9°F	51.8°F	54.9°F
Oct 2	55.8°F	52.4°F	54.8°F
Oct 3	56.1°F	53.3°F	54.8°F
Oct 4	57.9°F	53.0°F	54.7°F
Oct 5	56.9°F	52.8°F	54.5°F
Oct 6	56.4°F	52.9°F	54.4°F
Oct 7	56.0°F	53.3°F	54.4°F
Oct 8	56.6°F	53.9°F	54.6°F
Oct 9	56.3°F	53.1°F	54.2°F
Oct 10	55.4°F	55.4°F	54.1°F
Oct 11	55.1°F	53.3°F	53.8°F
Oct 12	54.6°F	52.5°F	53.3°F
Oct 13	54.7°F	52.6°F	53.3°F
Oct 14	54.6°F	54.5°F	53.3°F
Oct 15	54.8°F	53.7°F	53.4°F
Oct 16	54.7°F	53.2°F	53.3°F
Oct 17	54.9°F	53.6°F	53.5°F

* actual - actual temperature values

** forecast - projected values for the next week

Real-time coastal temperatures could deviate by several degrees from the provided readings. These deviations often become evident following intense rainfall or strong winds.

Our forecasting methodology leverages a mathematical model, that uses current water and weather conditions, historical records, wind intensity and direction.

Sea water temperature in Eureka by month

In an average year, Eureka offers no days when the water temperature is warm enough to swim comfortably.

The warmest water in Eureka was recorded on August 12, 2022, reaching a 61.8°F. While the coldest temperature occurred on June 7, 2025, dipping to 44.2°F. The average readings by season are 52.1°F in Winter, 51.3°F in Spring, 53.9°F in Summer, and 54.2°F in Autumn.