Tides Today & Tomorrow in Alcatraz Island, CA

TIDE TIMES for Sunday, October 18, 2026
The tide is currently falling in Alcatraz Island, CA.

Next low tide (tomorrow) : in 6h 59m at 1:00 am (0.7 ft)
Next high tide (tomorrow) : 8:41 am (4.5 ft)
Sunset today : 6:28 pm
Sunrise tomorrow : 7:21 am
Moon phase : First Quarter (51% illuminated)
Tide Station Location : Station #9414792
Common Questions About Tides

Alcatraz Island, CA Tides - Aug 1821

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Date		High Tide				Low Tide				Sun		Moon	Date
Date		AM	ft	PM	ft	AM	ft	PM	ft	Rise	Set	Moon	Date
1	Wed	12:54	5.5	2:23	5.2	7:26	0.2	7:54	2.2	5:19	7:25		1	Wed
2	Thu	1:38	5.0	2:51	5.3	7:57	0.7	8:44	2.0	5:20	7:24		2	Thu
3	Fri	2:27	4.5	3:19	5.4	8:28	1.3	9:40	1.9	5:21	7:23		3	Fri
4	Sat	3:26	4.0	3:52	5.4	9:02	2.0	10:42	1.7	5:22	7:22		4	Sat
5	Sun	4:47	3.6	4:30	5.5	9:40	2.6	11:49	1.4	5:23	7:21		5	Sun
6	Mon	6:41	3.5	5:17	5.6	10:34	3.1			5:23	7:20		6	Mon
7	Tue	8:31	3.8	6:10	5.7	12:53	1.1	11:49 AM	3.5	5:24	7:19		7	Tue
8	Wed	9:32	4.1	7:06	5.8	1:50	0.7	1:05	3.6	5:25	7:18		8	Wed
9	Thu	10:12	4.3	7:59	6.1	2:39	0.2	2:04	3.5	5:26	7:17		9	Thu
10	Fri	10:45	4.5	8:50	6.3	3:23	-0.2	2:54	3.4	5:27	7:16		10	Fri
11	Sat	11:15	4.7	9:38	6.5	4:02	-0.5	3:38	3.1	5:28	7:14		11	Sat
12	Sun	11:45	4.9	10:25	6.6	4:40	-0.7	4:21	2.8	5:29	7:13		12	Sun
13	Mon			12:15	5.1	5:16	-0.8	5:06	2.4	5:29	7:12		13	Mon
14	Tue			12:45	5.3	5:52	-0.7	5:54	2.0	5:30	7:11		14	Tue
15	Wed	12:02	6.3	1:16	5.6	6:28	-0.4	6:45	1.6	5:31	7:10		15	Wed
16	Thu	12:55	5.8	1:50	5.9	7:05	0.1	7:39	1.2	5:32	7:08		16	Thu
17	Fri	1:53	5.3	2:26	6.1	7:44	0.8	8:40	0.9	5:33	7:07		17	Fri
18	Sat	3:01	4.7	3:07	6.3	8:25	1.6	9:47	0.7	5:34	7:06		18	Sat
19	Sun	4:23	4.2	3:54	6.4	9:14	2.3	11:02	0.4	5:35	7:04		19	Sun
20	Mon	6:02	4.0	4:51	6.3	10:17	3.0			5:36	7:03		20	Mon
21	Tue	7:41	4.2	5:56	6.3	12:19	0.2	11:38 AM	3.3	5:36	7:02		21	Tue
22	Wed	8:53	4.5	7:03	6.3	1:30	0.0	1:01	3.4	5:37	7:00		22	Wed
23	Thu	9:45	4.8	8:06	6.3	2:31	-0.3	2:10	3.2	5:38	6:59		23	Thu
24	Fri	10:27	5.0	9:02	6.3	3:22	-0.4	3:07	2.9	5:39	6:58		24	Fri
25	Sat	11:04	5.1	9:52	6.3	4:05	-0.4	3:55	2.6	5:40	6:56		25	Sat
26	Sun	11:36	5.2	10:37	6.1	4:42	-0.3	4:39	2.3	5:41	6:55		26	Sun
27	Mon			12:06	5.3	5:16	-0.1	5:20	2.0	5:42	6:53		27	Mon
28	Tue			12:32	5.3	5:46	0.2	5:59	1.8	5:42	6:52		28	Tue
29	Wed	12:01	5.5	12:56	5.4	6:15	0.6	6:38	1.6	5:43	6:50		29	Wed
30	Thu	12:43	5.2	1:19	5.4	6:43	1.1	7:17	1.4	5:44	6:49		30	Thu
31	Fri	1:26	4.8	1:43	5.5	7:11	1.6	7:59	1.3	5:45	6:48		31	Fri
Date		High Tide				Low Tide				Sun		Moon	Date
Date		AM	ft	PM	ft	AM	ft	PM	ft	Rise	Set	Moon	Date

Tidal Data Source: (9414792)

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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 51% 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 (51% 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

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