Tides Today & Tomorrow in Alcatraz Island, CA

TIDE TIMES for Monday, August 17, 2026
The tide is currently rising in Alcatraz Island, CA.
Next low tide : 10:27 pm (1.2 ft)
Next high tide : in 4h 38m at 3:56 pm (5.8 ft)
Sunset today : 8:00 pm
Sunrise tomorrow : 6:27 am
Moon phase : Waxing Crescent (28% illuminated)
Tide Station Location : Station #9414792
Common Questions About Tides

Alcatraz Island, CA Tides - Apr 1944

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat6:474.89:234.61:202.92:010.36:547:32First Quarter1Sat
2Sun7:564.810:074.72:282.72:570.36:527:33Waxing Gibbous2Sun
3Mon8:584.810:424.83:232.33:430.36:517:34Waxing Gibbous3Mon
4Tue9:514.911:124.94:072.04:220.36:497:35Waxing Gibbous4Tue
5Wed10:374.911:375.04:461.64:560.46:487:36Waxing Gibbous5Wed
6Thu11:204.95:211.35:270.56:467:37Full Moon6Thu
7Fri12:025.112:024.95:541.05:560.76:457:38Full Moon7Fri
8Sat12:265.212:434.86:250.76:251.06:437:38Full Moon8Sat
9Sun12:515.31:254.76:580.46:541.36:427:39Full Moon9Sun
10Mon1:175.42:094.67:320.27:261.76:417:40Waning Gibbous10Mon
11Tue1:465.52:584.48:100.08:002.06:397:41Waning Gibbous11Tue
12Wed2:185.53:544.28:53-0.18:412.46:387:42Waning Gibbous12Wed
13Thu2:565.45:004.19:42-0.29:312.86:367:43Waning Gibbous13Thu
14Fri3:425.36:154.110:41-0.210:403.06:357:44Third Quarter14Fri
15Sat4:415.27:304.211:48-0.26:337:45Third Quarter15Sat
16Sun5:535.18:304.512:083.012:57-0.26:327:46Third Quarter16Sun
17Mon7:125.09:184.81:322.72:01-0.36:317:47Third Quarter17Mon
18Tue8:275.110:005.22:392.22:58-0.36:297:48Waning Crescent18Tue
19Wed9:355.310:385.53:351.53:48-0.36:287:49Waning Crescent19Wed
20Thu10:375.311:155.84:260.84:350.06:277:49Waning Crescent20Thu
21Fri11:365.411:516.15:140.25:190.36:257:50New Moon21Fri
22Sat12:325.36:01-0.46:020.76:247:51New Moon22Sat
23Sun12:286.21:285.16:48-0.76:461.26:237:52New Moon23Sun
24Mon1:046.22:245.07:34-0.97:311.76:217:53Waxing Crescent24Mon
25Tue1:426.13:224.88:21-0.98:192.26:207:54Waxing Crescent25Tue
26Wed2:225.84:244.69:10-0.79:132.66:197:55Waxing Crescent26Wed
27Thu3:055.55:314.510:03-0.410:192.96:187:56Waxing Crescent27Thu
28Fri3:535.16:414.411:00-0.111:383.06:167:57First Quarter28Fri
29Sat4:514.77:454.512:030.16:157:58First Quarter29Sat
30Sun5:594.48:364.612:582.81:050.36:147:59First Quarter30Sun
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (9414792)

Common Questions About Alcatraz Island, CA Tides

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

Slack tide in Alcatraz Island, CA is approximately 7:11 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 Alcatraz Island, CA?

Alcatraz Island, CA is currently in a transitional phase. Tonight's moon is 28% 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 Alcatraz Island, 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 Alcatraz Island, CA?

Tide predictions for Alcatraz Island, 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 Alcatraz Island, CA?

Tide data for Alcatraz Island, CA is sourced from NOAA Station #9414792. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=9414792.

What is the moon phase in Alcatraz Island, CA tonight?

Tonight the moon over Alcatraz Island, CA is Waxing Crescent (28% illuminated). This places Alcatraz Island, 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