Tides Today & Tomorrow in Alcatraz Island, CA

TIDE TIMES for Friday, July 31, 2026
The tide is currently falling in Alcatraz Island, CA.
Next low tide : in 3h 28m at 7:35 pm (2.5 ft)
Next high tide (tomorrow) : 1:29 am (5.6 ft)
Sunset today : 8:19 pm
Sunrise tomorrow : 6:12 am
Moon phase : Waning Gibbous (95% illuminated)
Tide Station Location : Station #9414792
Common Questions About Tides

Alcatraz Island, CA Tides - Aug 1974

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Thu12:414.85:38-0.25:242.86:128:18Full Moon1Thu
2Fri1:104.96:10-0.26:022.66:138:17Full Moon2Fri
3Sat1:364.96:40-0.16:382.56:148:16Full Moon3Sat
4Sun12:335.82:015.07:080.17:142.36:158:15Full Moon4Sun
5Mon1:105.52:265.27:360.37:522.26:168:14Waning Gibbous5Mon
6Tue1:495.22:525.38:040.68:322.06:178:13Waning Gibbous6Tue
7Wed2:314.93:225.58:341.09:181.86:188:12Waning Gibbous7Wed
8Thu3:194.53:545.69:071.510:101.66:188:11Waning Gibbous8Thu
9Fri4:204.14:335.79:452.011:121.46:198:10Third Quarter9Fri
10Sat5:403.85:195.810:312.56:208:09Third Quarter10Sat
11Sun7:193.76:146.012:221.111:33 AM2.96:218:08Third Quarter11Sun
12Mon8:493.97:156.21:320.612:483.16:228:06Third Quarter12Mon
13Tue9:544.28:176.42:350.22:023.16:238:05Waning Crescent13Tue
14Wed10:424.69:186.73:30-0.33:072.96:248:04Waning Crescent14Wed
15Thu11:244.910:156.84:19-0.74:052.56:248:03Waning Crescent15Thu
16Fri12:025.25:05-0.94:592.16:258:01New Moon16Fri
17Sat12:405.55:49-0.85:521.66:268:00New Moon17Sat
18Sun12:056.71:185.86:31-0.66:451.26:277:59New Moon18Sun
19Mon1:006.41:566.17:13-0.27:390.96:287:58Waxing Crescent19Mon
20Tue1:555.92:356.27:540.38:350.76:297:56Waxing Crescent20Tue
21Wed2:545.43:156.38:371.09:340.76:307:55Waxing Crescent21Wed
22Thu3:574.93:596.29:231.710:380.76:317:53First Quarter22Thu
23Fri5:114.44:486.110:162.311:480.76:317:52First Quarter23Fri
24Sat6:394.25:445.911:222.86:327:51First Quarter24Sat
25Sun8:104.26:455.81:000.712:413.16:337:49First Quarter25Sun
26Mon9:224.47:485.72:080.61:553.16:347:48Waxing Gibbous26Mon
27Tue10:144.68:465.73:050.42:563.06:357:46Waxing Gibbous27Tue
28Wed10:544.89:375.83:520.33:472.86:367:45Waxing Gibbous28Wed
29Thu11:274.910:225.84:310.34:292.56:377:44Waxing Gibbous29Thu
30Fri11:555.011:035.85:050.35:072.26:377:42Full Moon30Fri
31Sat12:205.15:360.35:422.06:387:41Full Moon31Sat
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 10:32 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 spring phase. Tonight's moon is 95% 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 maximum.

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 Waning Gibbous (95% illuminated). This places Alcatraz Island, CA in a spring tide cycle, so tidal ranges are near their weekly maximum 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