37.8267’ N, 122.4170’ W

Alcatraz Island, CA

64°
H -°
L 57°
WSW
17mph
Low tide
12:56 am

Tides Today & Tomorrow in Alcatraz Island, CA

TIDE TIMES for Friday, September 18, 2026
The tide is currently falling in Alcatraz Island, CA.
Next low tide (tomorrow) : in 6h 46m at 12:56 am (0.9 ft)
Next high tide (tomorrow) : 8:58 am (4.3 ft)
Sunset today : 7:13 pm
Sunrise tomorrow : 6:54 am
Moon phase : First Quarter (49% illuminated)
Tide Station Location : Station #9414792
Common Questions About Tides

Alcatraz Island, CA Tides - Sep 1876

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri11:054.89:535.94:080.04:032.65:476:45Waxing Gibbous1Fri
2Sat11:285.010:335.84:380.04:372.35:476:44Full Moon2Sat
3Sun11:515.111:135.75:060.15:112.05:486:42Full Moon3Sun
4Mon12:145.35:330.35:471.75:496:41Full Moon4Mon
5Tue12:385.56:010.66:241.35:506:39Waning Gibbous5Tue
6Wed12:405.21:045.76:301.17:061.05:516:38Waning Gibbous6Wed
7Thu1:304.91:335.97:021.67:530.85:526:36Waning Gibbous7Thu
8Fri2:294.52:076.07:372.28:470.65:536:34Waning Gibbous8Fri
9Sat3:434.22:496.08:182.89:520.55:536:33Third Quarter9Sat
10Sun5:184.03:436.09:133.311:080.35:546:31Third Quarter10Sun
11Mon6:594.14:526.010:353.65:556:30Third Quarter11Mon
12Tue8:124.46:086.012:260.112:103.55:566:28Third Quarter12Tue
13Wed9:014.77:216.21:34-0.21:283.25:576:27Waning Crescent13Wed
14Thu9:405.08:276.32:31-0.42:292.75:586:25Waning Crescent14Thu
15Fri10:165.39:266.33:19-0.53:232.15:586:24Waning Crescent15Fri
16Sat10:495.510:216.24:01-0.44:131.55:596:22New Moon16Sat
17Sun11:225.811:145.94:41-0.15:011.06:006:21New Moon17Sun
18Mon11:535.95:180.35:470.66:016:19New Moon18Mon
19Tue12:075.612:246.15:540.96:330.46:026:17Waxing Crescent19Tue
20Wed1:015.212:556.16:301.57:190.36:036:16Waxing Crescent20Wed
21Thu1:584.81:276.07:082.28:070.36:046:14Waxing Crescent21Thu
22Fri3:014.52:015.87:492.88:590.56:046:13Waxing Crescent22Fri
23Sat4:174.22:425.58:383.310:000.66:056:11First Quarter23Sat
24Sun5:504.23:345.39:513.611:100.76:066:10First Quarter24Sun
25Mon7:174.34:405.111:263.76:076:08First Quarter25Mon
26Tue8:144.55:535.012:210.712:453.56:086:07First Quarter26Tue
27Wed8:524.67:005.11:210.61:423.26:096:05Waxing Gibbous27Wed
28Thu9:214.77:585.22:090.52:272.86:106:03Waxing Gibbous28Thu
29Fri9:454.98:485.32:480.43:062.36:116:02Waxing Gibbous29Fri
30Sat10:085.19:355.33:220.43:411.96:116:00Waxing Gibbous30Sat
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (9414792)

Common Questions About Alcatraz Island, CA Tides

Collapse All
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 49% 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 (49% 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