Tides Today & Tomorrow in Alcatraz Island, CA

TIDE TIMES for Tuesday, July 21, 2026
The tide is currently rising in Alcatraz Island, CA.
Next low tide (tomorrow) : 1:31 am (1.0 ft)
Next high tide : in 2h 04m at 6:21 pm (5.8 ft)
Sunset today : 8:27 pm
Sunrise tomorrow : 6:04 am
Moon phase : First Quarter (53% illuminated)
Tide Station Location : Station #9414792
Common Questions About Tides

Alcatraz Island, CA Tides - Feb 1987

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun2:035.51:265.77:281.87:48-0.37:135:32Waxing Crescent1Sun
2Mon2:395.72:235.08:271.68:270.57:125:33Waxing Crescent2Mon
3Tue3:175.73:284.39:301.49:081.37:125:34First Quarter3Tue
4Wed3:565.74:503.810:391.29:552.17:115:36First Quarter4Wed
5Thu4:385.76:383.611:511.010:552.87:105:37First Quarter5Thu
6Fri5:255.68:223.91:010.77:095:38First Quarter6Fri
7Sat6:195.69:314.212:113.22:020.47:085:39Waxing Gibbous7Sat
8Sun7:145.610:184.41:263.42:530.17:075:40Waxing Gibbous8Sun
9Mon8:075.710:544.62:273.43:36-0.17:065:41Waxing Gibbous9Mon
10Tue8:555.811:254.73:153.24:14-0.37:055:42Waxing Gibbous10Tue
11Wed9:385.911:524.73:563.04:47-0.47:045:43Waxing Gibbous11Wed
12Thu10:185.94:322.85:16-0.47:025:44Full Moon12Thu
13Fri12:174.810:56 AM5.95:062.65:44-0.47:015:46Full Moon13Fri
14Sat12:414.911:34 AM5.85:412.36:11-0.37:005:47Full Moon14Sat
15Sun1:045.012:135.56:172.06:380.06:595:48Full Moon15Sun
16Mon1:295.212:555.26:561.87:060.46:585:49Waning Gibbous16Mon
17Tue1:555.31:424.87:391.57:370.96:575:50Waning Gibbous17Tue
18Wed2:235.52:384.38:291.28:101.56:555:51Waning Gibbous18Wed
19Thu2:555.73:533.89:270.98:492.26:545:52Third Quarter19Thu
20Fri3:355.85:383.610:360.69:402.86:535:53Third Quarter20Fri
21Sat4:275.87:353.811:520.310:573.36:525:54Third Quarter21Sat
22Sun5:315.98:544.11:07-0.16:505:55Third Quarter22Sun
23Mon6:436.19:444.512:323.52:13-0.66:495:56Waning Crescent23Mon
24Tue7:526.310:244.81:513.33:08-0.96:485:57Waning Crescent24Tue
25Wed8:556.511:015.02:552.83:56-1.16:465:58Waning Crescent25Wed
26Thu9:526.511:355.23:502.44:40-1.26:455:59New Moon26Thu
27Fri10:466.44:411.85:20-1.06:446:00New Moon27Fri
28Sat12:095.511:37 AM6.25:301.45:58-0.66:426:01New Moon28Sat
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 9:56 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 neap phase. Tonight's moon is 53% 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 near their weekly minimum.

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 First Quarter (53% illuminated). This places Alcatraz Island, CA in a neap tide cycle, so tidal ranges are near their weekly minimum 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