Tides Today & Tomorrow in Alcatraz Island, CA

TIDE TIMES for Saturday, July 18, 2026
The tide is currently rising in Alcatraz Island, CA.
Next low tide : 10:04 pm (1.9 ft)
Next high tide : in 2h 49m at 4:18 pm (5.6 ft)
Sunset today : 8:29 pm
Sunrise tomorrow : 6:02 am
Moon phase : Waxing Crescent (24% illuminated)
Tide Station Location : Station #9414792
Common Questions About Tides

Alcatraz Island, CA Tides - Jun 2072

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed12:046.31:554.86:50-1.06:392.55:488:26Full Moon1Wed
2Thu12:426.12:434.87:30-1.07:262.75:488:27Full Moon2Thu
3Fri1:205.93:294.88:10-0.88:152.85:488:28Waning Gibbous3Fri
4Sat1:595.54:144.78:51-0.69:082.95:488:28Waning Gibbous4Sat
5Sun2:405.24:594.79:33-0.310:082.95:478:29Waning Gibbous5Sun
6Mon3:264.85:434.710:170.011:162.85:478:29Waning Gibbous6Mon
7Tue4:194.46:274.811:040.45:478:30Third Quarter7Tue
8Wed5:234.07:094.912:262.611:54 AM0.85:478:30Third Quarter8Wed
9Thu6:383.77:485.11:292.212:451.15:478:31Third Quarter9Thu
10Fri7:573.78:265.42:241.71:361.45:478:31Third Quarter10Fri
11Sat9:103.79:025.63:101.22:241.75:478:32Waning Crescent11Sat
12Sun10:143.99:385.93:510.73:101.95:478:32Waning Crescent12Sun
13Mon11:104.210:156.14:290.13:542.25:478:33Waning Crescent13Mon
14Tue12:014.45:06-0.44:382.35:478:33New Moon14Tue
15Wed12:494.65:45-0.85:232.55:478:33New Moon15Wed
16Thu1:364.86:26-1.16:102.65:478:34New Moon16Thu
17Fri12:186.52:224.97:08-1.36:592.65:478:34New Moon17Fri
18Sat1:046.53:095.17:53-1.37:532.65:478:34Waxing Crescent18Sat
19Sun1:536.33:565.28:40-1.28:532.55:478:35Waxing Crescent19Sun
20Mon2:475.94:455.39:29-0.910:012.45:488:35Waxing Crescent20Mon
21Tue3:475.45:355.510:20-0.411:172.15:488:35First Quarter21Tue
22Wed4:564.86:265.711:150.15:488:35First Quarter22Wed
23Thu6:164.47:176.012:341.712:130.75:488:35First Quarter23Thu
24Fri7:424.18:066.21:451.11:131.25:498:35First Quarter24Fri
25Sat9:054.18:536.42:480.62:121.65:498:35Waxing Gibbous25Sat
26Sun10:184.39:386.53:430.03:082.05:498:35Waxing Gibbous26Sun
27Mon11:194.510:216.54:32-0.34:002.35:508:36Waxing Gibbous27Mon
28Tue12:124.75:15-0.64:502.55:508:35Full Moon28Tue
29Wed1:004.85:56-0.75:372.75:518:35Full Moon29Wed
30Thu1:434.96:34-0.76:222.85:518:35Full Moon30Thu
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 24% 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 (24% 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