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 11.08°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.

51.9

°F

October 13, 05:00

Trend:

stable

Yesterday:

52.4°F

Tomorrow:

52.0°F

Sunrise:

07:26

Sunset:

18:40

Day Length:

11 h. 14 min.

Eureka in October

Minimum:

50.5°F

Average:

52.3°F

Maximum:

54.1°F

Sea water temperature in Eureka today

As of now, in Eureka, the water temperature is 51.9°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 1.0°F lower 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 stay about the same.

Recent sea temperature and forecast

Today's water temperature is considerably lower than the average registered over the last two weeks, indicating a slight cooling trend. It is also close to the historical minimum temperature for this date. The maximum temperature recorded for this date was 56.1°F on 2020, while the historical minimum was 51.1°F on 2019.

latest data

last year

Over the past two weeks, the water temperature has closely aligned with historical averages for those days. Over the next week, the forecast shows a steady trend, with temperatures staying close to the average of 52.0°F. Both minimum and maximum temperatures expected to be close to the average, offering a week of stable water conditions.

Daily water temperature in Eureka

Date	Current Year actual* / forecast**	last year	10 years average
Sep 29	54.9°F	55.8°F	55.0°F
Sep 30	55.3°F	55.0°F	55.1°F
Oct 1	55.5°F	54.9°F	54.9°F
Oct 2	55.8°F	55.8°F	54.8°F
Oct 3	55.7°F	56.1°F	54.8°F
Oct 4	55.5°F	57.9°F	54.8°F
Oct 5	53.8°F	56.9°F	54.5°F
Oct 6	54.6°F	56.4°F	54.4°F
Oct 7	55.6°F	56.0°F	54.4°F
Oct 8	55.9°F	56.6°F	54.7°F
Oct 9	54.0°F	56.3°F	54.1°F
Oct 10	54.6°F	55.4°F	54.1°F
Oct 11	53.3°F	55.3°F	53.6°F
Oct 12	52.4°F	54.7°F	53.0°F
Oct 13	51.9°F	54.0°F	53.0°F
Oct 14	52.0°F	55.1°F	53.0°F
Oct 15	52.1°F	54.5°F	53.1°F
Oct 16	52.1°F	55.0°F	53.1°F
Oct 17	52.2°F	54.7°F	53.2°F
Oct 18	52.1°F	55.1°F	53.1°F
Oct 19	51.8°F	54.8°F	52.8°F
Oct 20	52.0°F	54.6°F	53.0°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 52.0°F in Winter, 51.3°F in Spring, 53.6°F in Summer, and 54.2°F in Autumn.