Tides Today & Tomorrow in Alcatraz Island, CA

TIDE TIMES for Friday, June 19, 2026
The tide is currently falling in Alcatraz Island, CA.
Next low tide : in 4h 39m at 10:33 pm (2.4 ft)
Next high tide (tomorrow) : 4:04 am (5.1 ft)
Sunset today : 8:34 pm
Sunrise tomorrow : 5:47 am
Moon phase : Waxing Crescent (28% illuminated)
Tide Station Location : Station #9414792
Common Questions About Tides

Alcatraz Island, CA Tides - Jun 2021

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue4:435.07:085.111:41-0.35:488:26Third Quarter1Tue
2Wed5:574.47:555.212:462.512:370.25:488:26Third Quarter2Wed
3Thu7:174.18:365.41:562.01:300.65:488:27Third Quarter3Thu
4Fri8:373.99:105.52:541.42:191.15:488:28Waning Crescent4Fri
5Sat9:483.99:415.73:430.93:031.55:478:28Waning Crescent5Sat
6Sun10:514.010:095.84:250.43:442.05:478:29Waning Crescent6Sun
7Mon11:464.110:375.95:030.14:232.45:478:29Waning Crescent7Mon
8Tue12:364.25:37-0.25:012.75:478:30New Moon8Tue
9Wed1:214.36:10-0.55:383.05:478:30New Moon9Wed
10Thu2:034.46:42-0.66:153.25:478:31New Moon10Thu
11Fri12:085.92:444.57:15-0.76:533.35:468:31New Moon11Fri
12Sat12:435.93:254.57:50-0.77:333.35:468:32Waxing Crescent12Sat
13Sun1:215.84:064.58:28-0.78:183.45:468:32Waxing Crescent13Sun
14Mon2:015.64:484.69:08-0.79:123.35:468:33Waxing Crescent14Mon
15Tue2:475.35:314.79:52-0.510:163.25:478:33Waxing Crescent15Tue
16Wed3:405.06:134.910:39-0.311:302.95:478:33First Quarter16Wed
17Thu4:444.66:535.111:290.15:478:34First Quarter17Thu
18Fri6:034.27:325.512:432.312:210.55:478:34First Quarter18Fri
19Sat7:314.08:115.91:481.61:141.05:478:34First Quarter19Sat
20Sun8:594.08:516.32:450.72:081.55:478:35Waxing Gibbous20Sun
21Mon10:184.29:336.73:38-0.13:012.05:478:35Waxing Gibbous21Mon
22Tue11:264.510:176.94:29-0.83:542.45:488:35Waxing Gibbous22Tue
23Wed12:274.75:18-1.34:482.75:488:35Full Moon23Wed
24Thu1:224.96:07-1.75:422.95:488:35Full Moon24Thu
25Fri2:145.06:56-1.86:373.05:498:35Full Moon25Fri
26Sat12:416.93:045.17:44-1.77:353.05:498:35Waning Gibbous26Sat
27Sun1:326.63:525.18:33-1.48:372.95:498:35Waning Gibbous27Sun
28Mon2:246.14:405.29:21-1.09:432.85:508:35Waning Gibbous28Mon
29Tue3:185.55:275.210:09-0.510:562.65:508:35Waning Gibbous29Tue
30Wed4:184.86:125.310:570.15:518:35Third Quarter30Wed
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (9414792)

Common Questions About Alcatraz Island, CA Tides

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

Slack tide in Alcatraz Island, CA is approximately 1:18 am — 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