Tides Today & Tomorrow in Eureka, CA

TIDE TIMES for Tuesday, August 18, 2026
The tide is currently rising in Eureka, CA.
Next low tide : 11:34 pm (1.1 ft)
Next high tide : in 4h 00m at 4:55 pm (7.1 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 - Aug 1938

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Mon3:426.04:137.39:221.110:291.15:127:33First Quarter1Mon
2Tue4:475.35:017.210:091.911:361.15:137:32First Quarter2Tue
3Wed6:034.95:527.111:022.65:147:30First Quarter3Wed
4Thu7:284.76:477.012:451.012:043.15:157:29First Quarter4Thu
5Fri8:514.87:437.01:500.81:113.35:167:28Waxing Gibbous5Fri
6Sat9:535.08:367.02:460.52:143.45:177:27Waxing Gibbous6Sat
7Sun10:385.39:247.13:330.33:083.25:187:26Waxing Gibbous7Sun
8Mon11:135.510:087.24:130.13:553.05:197:25Waxing Gibbous8Mon
9Tue11:435.710:497.34:49-0.14:372.75:207:23Full Moon9Tue
10Wed12:126.05:22-0.15:162.55:217:22Full Moon10Wed
11Thu12:416.25:54-0.15:542.25:227:21Full Moon11Thu
12Fri12:067.11:106.46:240.06:332.05:237:19Full Moon12Fri
13Sat12:446.91:396.66:540.37:131.85:247:18Waning Gibbous13Sat
14Sun1:256.62:096.87:250.77:551.65:257:17Waning Gibbous14Sun
15Mon2:086.22:416.97:571.18:431.45:267:15Waning Gibbous15Mon
16Tue2:585.83:177.18:311.69:371.25:277:14Waning Gibbous16Tue
17Wed3:585.34:007.29:102.110:381.05:287:13Third Quarter17Wed
18Thu5:094.94:527.39:592.611:470.85:297:11Third Quarter18Thu
19Fri6:314.85:547.411:033.05:307:10Third Quarter19Fri
20Sat7:534.97:027.612:570.412:223.25:317:08Waning Crescent20Sat
21Sun9:025.38:087.82:02-0.11:393.05:327:07Waning Crescent21Sun
22Mon9:565.89:118.03:00-0.52:472.65:337:05Waning Crescent22Mon
23Tue10:436.310:098.23:51-0.83:472.15:347:04Waning Crescent23Tue
24Wed11:256.711:048.24:37-0.94:421.55:357:02New Moon24Wed
25Thu12:057.25:21-0.85:341.05:367:01New Moon25Thu
26Fri12:447.56:03-0.56:240.65:376:59New Moon26Fri
27Sat12:477.61:227.66:440.07:130.45:386:58Waxing Crescent27Sat
28Sun1:387.12:017.67:240.68:040.45:396:56Waxing Crescent28Sun
29Mon2:306.52:417.58:041.38:560.65:406:55Waxing Crescent29Mon
30Tue3:265.93:237.38:462.09:510.85:416:53First Quarter30Tue
31Wed4:285.44:107.09:332.710:521.05:426:51First Quarter31Wed
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 8:14 pm — 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