Tides Today & Tomorrow in Rio Vista, CA

TIDE TIMES for Friday, August 21, 2026
The tide is currently falling in Rio Vista, CA.
Next low tide : in 4h 19m at 4:53 pm (1.9 ft)
Next high tide : 11:21 pm (4.0 ft)
Sunset today : 7:52 pm
Sunrise tomorrow : 6:27 am
Moon phase : First Quarter (66% illuminated)
Tide Station Location : Station #9415316
Common Questions About Tides

Rio Vista, CA Tides - Jan 1935

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue12:522.411:34 AM4.15:181.58:070.37:234:57Waning Crescent1Tue
2Wed1:472.512:154.36:111.68:540.07:234:58Waning Crescent2Wed
3Thu2:372.61:004.47:101.79:39-0.27:234:58New Moon3Thu
4Fri3:232.71:494.58:131.710:21-0.37:234:59New Moon4Fri
5Sat4:072.82:394.59:141.611:02-0.37:235:00New Moon5Sat
6Sun4:483.03:324.410:121.511:41-0.37:235:01New Moon6Sun
7Mon5:303.24:284.211:101.37:235:02Waxing Crescent7Mon
8Tue6:123.45:283.912:20-0.112:101.27:235:03Waxing Crescent8Tue
9Wed6:563.76:333.51:000.11:161.27:235:04Waxing Crescent9Wed
10Thu7:433.97:473.21:410.32:271.17:235:05First Quarter10Thu
11Fri8:324.19:082.82:240.53:441.07:235:06First Quarter11Fri
12Sat9:234.210:302.73:110.85:000.87:235:07First Quarter12Sat
13Sun10:164.311:462.64:021.16:100.57:225:08Waxing Gibbous13Sun
14Mon11:074.34:571.37:110.27:225:09Waxing Gibbous14Mon
15Tue12:522.711:55 AM4.35:531.58:040.07:225:10Waxing Gibbous15Tue
16Wed1:492.912:394.36:501.78:51-0.27:215:11Waxing Gibbous16Wed
17Thu2:403.01:214.37:441.79:33-0.27:215:12Full Moon17Thu
18Fri3:253.12:024.38:361.810:10-0.27:215:13Full Moon18Fri
19Sat4:073.22:424.29:231.710:440.07:205:14Full Moon19Sat
20Sun4:443.33:224.110:081.711:140.17:205:15Full Moon20Sun
21Mon5:193.34:034.010:511.611:400.37:195:16Waning Gibbous21Mon
22Tue5:513.44:453.811:341.57:195:17Waning Gibbous22Tue
23Wed6:193.55:293.612:040.412:191.57:185:18Waning Gibbous23Wed
24Thu6:453.56:183.312:270.61:081.57:175:19Waning Gibbous24Thu
25Fri7:083.67:183.012:530.82:071.57:175:21Waning Gibbous25Fri
26Sat7:353.78:372.71:261.03:181.47:165:22Third Quarter26Sat
27Sun8:113.810:052.52:061.24:331.27:155:23Third Quarter27Sun
28Mon8:573.911:232.52:541.45:431.07:155:24Third Quarter28Mon
29Tue9:524.03:491.66:450.77:145:25Waning Crescent29Tue
30Wed12:292.610:53 AM4.14:511.77:390.47:135:26Waning Crescent30Wed
31Thu1:232.711:54 AM4.35:591.88:280.27:125:27Waning Crescent31Thu
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (9415316)

Common Questions About Rio Vista, CA Tides

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What time does the tide turn (slack tide) in Rio Vista, CA today?

Slack tide in Rio Vista, CA is approximately 8:07 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 Rio Vista, CA?

Rio Vista, CA is currently in a transitional phase. Tonight's moon is 66% 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 Rio Vista, 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 Rio Vista, CA?

Tide predictions for Rio Vista, 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 Rio Vista, CA?

Tide data for Rio Vista, CA is sourced from NOAA Station #9415316. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=9415316.

What is the moon phase in Rio Vista, CA tonight?

Tonight the moon over Rio Vista, CA is First Quarter (66% illuminated). This places Rio Vista, 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