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 4h 23m 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 - Oct 1931

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Thu2:545.41:547.07:343.18:520.56:126:00Waning Gibbous1Thu
2Fri3:515.12:276.98:043.69:440.66:135:58Waning Gibbous2Fri
3Sat5:024.93:136.78:433.910:470.66:145:57Third Quarter3Sat
4Sun6:244.84:196.69:484.211:570.56:155:55Third Quarter4Sun
5Mon7:405.05:446.511:324.26:165:53Third Quarter5Mon
6Tue8:335.37:066.61:040.31:033.86:175:52Waning Crescent6Tue
7Wed9:135.88:186.82:020.12:133.06:185:50Waning Crescent7Wed
8Thu9:486.49:227.12:52-0.13:102.16:195:48Waning Crescent8Thu
9Fri10:227.010:217.23:37-0.14:021.16:205:47Waning Crescent9Fri
10Sat10:557.611:187.24:190.14:520.16:215:45New Moon10Sat
11Sun11:308.14:590.65:40-0.66:225:44New Moon11Sun
12Mon12:147.012:058.55:391.26:29-1.26:245:42New Moon12Mon
13Tue1:106.812:438.66:201.87:18-1.36:255:41Waxing Crescent13Tue
14Wed2:086.41:238.47:032.58:09-1.26:265:39Waxing Crescent14Wed
15Thu3:096.02:078.17:493.19:04-0.96:275:37Waxing Crescent15Thu
16Fri4:165.72:587.58:423.610:03-0.46:285:36First Quarter16Fri
17Sat5:325.53:586.99:493.911:090.16:295:34First Quarter17Sat
18Sun6:505.55:116.411:144.06:305:33First Quarter18Sun
19Mon7:565.76:296.012:170.412:433.76:315:31First Quarter19Mon
20Tue8:455.97:435.91:200.61:563.26:325:30Waxing Gibbous20Tue
21Wed9:216.28:465.92:130.82:512.66:335:28Waxing Gibbous21Wed
22Thu9:496.49:405.92:561.03:351.96:355:27Waxing Gibbous22Thu
23Fri10:156.710:285.93:331.24:131.36:365:26Waxing Gibbous23Fri
24Sat10:397.011:126.04:061.54:490.86:375:24Full Moon24Sat
25Sun11:037.211:555.94:361.95:230.36:385:23Full Moon25Sun
26Mon11:277.45:062.35:560.06:395:21Full Moon26Mon
27Tue12:375.911:51 AM7.55:352.76:31-0.26:405:20Full Moon27Tue
28Wed1:205.812:177.56:053.17:07-0.36:415:19Waning Gibbous28Wed
29Thu2:055.612:447.56:353.47:46-0.36:435:17Waning Gibbous29Thu
30Fri2:555.51:157.37:073.88:30-0.26:445:16Waning Gibbous30Fri
31Sat3:515.31:547.17:464.09:20-0.16:455:15Waning Gibbous31Sat
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 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