Tides Today & Tomorrow in Eureka, CA

TIDE TIMES for Tuesday, August 18, 2026
The tide is currently falling in Eureka, CA.
Next low tide : in 6h 17m at 11:34 pm (1.1 ft)
Next high tide (tomorrow) : 6:07 am (4.8 ft)
Sunset today : 8:10 pm
Sunrise tomorrow : 6:30 am
Moon phase : First Quarter (37% illuminated)
Tide Station Location : Station #9418801
Common Questions About Tides

Eureka, CA Tides - Feb 1938

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue1:026.512:177.56:072.66:41-0.17:275:33New Moon1Tue
2Wed1:316.712:567.36:472.47:120.17:265:34Waxing Crescent2Wed
3Thu2:026.91:376.97:302.27:430.57:255:36Waxing Crescent3Thu
4Fri2:337.12:236.48:161.98:161.07:245:37Waxing Crescent4Fri
5Sat3:077.33:165.99:071.78:521.67:235:38Waxing Crescent5Sat
6Sun3:467.54:215.410:061.59:342.27:215:39First Quarter6Sun
7Mon4:317.65:395.011:131.210:262.77:205:41First Quarter7Mon
8Tue5:267.77:074.912:250.87:195:42First Quarter8Tue
9Wed6:297.98:315.11:350.37:185:43Waxing Gibbous9Wed
10Thu7:358.09:395.512:553.42:38-0.27:175:44Waxing Gibbous10Thu
11Fri8:408.310:326.02:113.23:33-0.67:165:45Waxing Gibbous11Fri
12Sat9:408.411:176.53:172.84:22-0.97:145:47Waxing Gibbous12Sat
13Sun10:368.511:586.94:152.35:07-1.07:135:48Full Moon13Sun
14Mon11:288.45:091.85:49-0.97:125:49Full Moon14Mon
15Tue12:367.312:188.16:001.46:29-0.67:115:50Full Moon15Tue
16Wed1:147.51:077.66:491.27:080.07:095:52Waning Gibbous16Wed
17Thu1:517.61:557.07:371.07:460.67:085:53Waning Gibbous17Thu
18Fri2:287.62:446.48:261.08:231.37:075:54Waning Gibbous18Fri
19Sat3:057.53:385.79:181.19:022.07:055:55Waning Gibbous19Sat
20Sun3:457.34:385.210:131.39:442.77:045:56Third Quarter20Sun
21Mon4:307.05:494.811:151.410:343.27:025:58Third Quarter21Mon
22Tue5:216.87:144.612:231.47:015:59Third Quarter22Tue
23Wed6:206.78:394.81:301.37:006:00Third Quarter23Wed
24Thu7:216.79:375.012:543.72:281.06:586:01Waning Crescent24Thu
25Fri8:206.810:175.42:033.63:160.76:576:02Waning Crescent25Fri
26Sat9:126.910:505.72:593.33:560.46:556:03Waning Crescent26Sat
27Sun9:597.111:196.03:472.94:320.36:546:05Waning Crescent27Sun
28Mon10:437.211:486.44:292.45:050.26:526:06New Moon28Mon
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (9418801)

Common Questions About Eureka, CA Tides

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What time does the tide turn (slack tide) in Eureka, CA today?

Slack tide in Eureka, CA is approximately 2:50 am — midway between the next high and low tide, when tidal current is weakest. This is the preferred window for boat crossings, underwater visibility, and fishing in areas with strong currents.

Is this week a spring tide or neap tide in Eureka, CA?

Eureka, CA is currently in a transitional phase. Tonight's moon is 37% illuminated. Spring tides (largest swings) occur near new and full moons; neap tides (smallest swings) occur near first and third quarter moons. Tidal ranges this week are shifting between spring and neap.

What datum are Eureka, CA tide heights measured from?

Tide heights on this page are measured from Mean Lower Low Water (MLLW), the U.S. NOAA standard. A height of 0 ft represents the 19-year average of each day's lower low tide. Negative values indicate a "minus tide" — water levels below that long-term reference.

What factors can affect the tide predictions for Eureka, CA?

Tide predictions for Eureka, CA come from NOAA's harmonic analysis and are typically accurate within about ±10 minutes on timing and ±0.5 ft on height. Actual water levels can deviate further due to sustained winds, atmospheric pressure changes, river flow, and storm surge. During major weather events, be sure to check US Harbors weather pages for factors that could impact tidal predictions.

Which NOAA station provides tide data for Eureka, CA?

Tide data for Eureka, CA is sourced from NOAA Station #9418801. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=9418801.

What is the moon phase in Eureka, CA tonight?

Tonight the moon over Eureka, CA is First Quarter (37% illuminated). This places Eureka, CA in a transitional tide cycle, so tidal ranges are shifting between spring and neap this week.

US Harbors Tidal Data

The data in our tide charts, tide tables, and tide graphs is provided by NOAA and others. These predictions are derived mathematically from numerous inputs, including data from historical tide stations and nearby locations where sensors are actively recording. As shown in the tide graph at the top of this page, “Predicted” tides (blue) are what forecasting models expect to happen. “Observed” tides (red) are those recorded by local sensors in real time, overlaid on the predictions for direct comparison. We display Observed water levels for a select group of harbors including Portland, Maine, where a physical sensor monitors water levels in real time.

LEARN MORE ABOUT OUR TIDE DATA