Tides Today & Tomorrow in Alcatraz Island, CA

TIDE TIMES for Saturday, June 20, 2026
The tide is currently falling in Alcatraz Island, CA.
Next low tide : in 4h 13m at 10:42 am (-0.2 ft)
Next high tide : 5:55 pm (5.4 ft)
Sunset today : 8:34 pm
Sunrise tomorrow : 5:47 am
Moon phase : First Quarter (38% illuminated)
Tide Station Location : Station #9414792
Common Questions About Tides

Alcatraz Island, CA Tides - Apr 2032

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Thu3:325.55:394.110:21-0.110:142.76:537:33Third Quarter1Thu
2Fri4:285.46:544.111:26-0.111:342.86:517:34Third Quarter2Fri
3Sat5:375.28:014.412:36-0.16:507:35Third Quarter3Sat
4Sun6:545.18:544.71:022.61:42-0.16:487:35Third Quarter4Sun
5Mon8:105.29:405.12:152.12:41-0.16:477:36Waning Crescent5Mon
6Tue9:195.310:205.43:161.53:32-0.16:457:37Waning Crescent6Tue
7Wed10:225.410:595.84:090.84:200.16:447:38Waning Crescent7Wed
8Thu11:205.411:366.04:590.25:040.46:427:39New Moon8Thu
9Fri12:165.35:46-0.35:480.76:417:40New Moon9Fri
10Sat12:146.21:105.26:32-0.66:311.16:407:41New Moon10Sat
11Sun12:516.22:035.07:17-0.77:151.56:387:42New Moon11Sun
12Mon1:306.12:584.88:03-0.78:012.06:377:43Waxing Crescent12Mon
13Tue2:095.93:544.68:50-0.58:502.36:357:44Waxing Crescent13Tue
14Wed2:515.64:554.49:40-0.39:482.66:347:45Waxing Crescent14Wed
15Thu3:375.26:014.310:340.010:592.86:327:45First Quarter15Thu
16Fri4:304.87:074.311:340.36:317:46First Quarter16Fri
17Sat5:334.58:044.412:172.712:370.56:307:47First Quarter17Sat
18Sun6:454.38:504.51:292.51:360.76:287:48First Quarter18Sun
19Mon7:554.29:264.72:292.12:270.86:277:49Waxing Gibbous19Mon
20Tue8:594.39:564.93:181.73:110.96:267:50Waxing Gibbous20Tue
21Wed9:554.310:245.14:001.23:491.06:247:51Waxing Gibbous21Wed
22Thu10:464.410:525.44:370.84:251.26:237:52Waxing Gibbous22Thu
23Fri11:334.511:215.65:110.44:581.46:227:53Full Moon23Fri
24Sat12:184.65:450.05:321.66:217:54Full Moon24Sat
25Sun1:044.66:19-0.36:071.86:197:55Full Moon25Sun
26Mon12:235.81:514.66:56-0.66:442.16:187:56Full Moon26Mon
27Tue12:585.92:394.67:35-0.87:252.36:177:57Waning Gibbous27Tue
28Wed1:365.93:314.58:19-0.98:112.56:167:57Waning Gibbous28Wed
29Thu2:205.84:274.59:07-0.89:062.76:147:58Waning Gibbous29Thu
30Fri3:105.65:274.510:01-0.710:152.76:137:59Waning Gibbous30Fri
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 2:18 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 38% 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 First Quarter (38% 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