Tides Today & Tomorrow in Eureka, CA

TIDE TIMES for Friday, August 21, 2026
The tide is currently rising in Eureka, CA.
Next low tide : 12:53 pm (4.0 ft)
Next high tide : in 1h 57m at 9:17 am (4.6 ft)
Sunset today : 8:06 pm
Sunrise tomorrow : 6:33 am
Moon phase : First Quarter (66% illuminated)
Tide Station Location : Station #9418801
Common Questions About Tides

Eureka, CA Tides - Jul 1931

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed2:075.76:52-1.46:333.34:487:52Full Moon1Wed
2Thu12:387.52:455.77:32-1.17:203.24:487:52Waning Gibbous2Thu
3Fri1:217.13:225.78:10-0.78:083.24:497:51Waning Gibbous3Fri
4Sat2:046.63:585.88:47-0.39:013.14:497:51Waning Gibbous4Sat
5Sun2:506.04:345.99:230.39:592.94:507:51Waning Gibbous5Sun
6Mon3:415.45:096.19:580.911:022.64:517:51Third Quarter6Mon
7Tue4:424.85:456.310:351.54:517:50Third Quarter7Tue
8Wed5:554.46:236.512:082.211:14 AM2.24:527:50Third Quarter8Wed
9Thu7:184.27:036.81:111.712:002.84:537:50Third Quarter9Thu
10Fri8:434.37:457.12:071.012:543.24:537:49Waning Crescent10Fri
11Sat9:574.68:307.42:570.41:533.54:547:49Waning Crescent11Sat
12Sun10:554.99:167.73:43-0.22:503.74:557:49Waning Crescent12Sun
13Mon11:425.210:038.04:27-0.83:433.64:557:48New Moon13Mon
14Tue12:235.55:10-1.34:343.54:567:48New Moon14Tue
15Wed1:035.75:52-1.65:233.34:577:47New Moon15Wed
16Thu1:415.96:34-1.86:143.04:587:46New Moon16Thu
17Fri12:268.22:206.27:15-1.77:072.74:587:46Waxing Crescent17Fri
18Sat1:167.92:596.47:57-1.48:042.34:597:45Waxing Crescent18Sat
19Sun2:107.33:396.88:38-0.89:062.05:007:44Waxing Crescent19Sun
20Mon3:106.64:217.19:200.010:131.65:017:44First Quarter20Mon
21Tue4:175.75:047.410:040.911:241.25:027:43First Quarter21Tue
22Wed5:365.15:527.610:521.85:037:42First Quarter22Wed
23Thu7:054.76:427.812:360.611:47 AM2.65:047:41First Quarter23Thu
24Fri8:404.77:377.91:450.112:523.25:047:41Waxing Gibbous24Fri
25Sat10:025.08:327.92:47-0.42:003.55:057:40Waxing Gibbous25Sat
26Sun11:025.39:267.93:42-0.73:043.65:067:39Waxing Gibbous26Sun
27Mon11:485.610:167.94:30-0.94:003.55:077:38Full Moon27Mon
28Tue12:275.75:14-1.04:503.35:087:37Full Moon28Tue
29Wed1:015.85:53-1.05:353.15:097:36Full Moon29Wed
30Thu1:325.96:30-0.86:182.95:107:35Full Moon30Thu
31Fri12:257.42:026.07:03-0.67:002.75:117:34Waning Gibbous31Fri
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (9418801)

Common Questions About Eureka, CA Tides

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

Slack tide in Eureka, CA is approximately 11:05 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 66% 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 (66% 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