Tides Today & Tomorrow in Rio Vista, CA

TIDE TIMES for Tuesday, August 18, 2026
The tide is currently rising in Rio Vista, CA.
Next low tide : 2:18 pm (1.2 ft)
Next high tide : in 4h 48m at 8:46 am (2.9 ft)
Sunset today : 7:56 pm
Sunrise tomorrow : 6:24 am
Moon phase : First Quarter (37% illuminated)
Tide Station Location : Station #9415316
Common Questions About Tides

Rio Vista, CA Tides - Apr 1940

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Mon10:493.25:061.46:070.35:516:29Waning Crescent1Mon
2Tue12:053.611:54 AM3.26:091.26:550.35:496:30Waning Crescent2Tue
3Wed12:493.712:503.27:071.07:390.45:486:31Waning Crescent3Wed
4Thu1:273.71:403.27:580.88:180.65:466:32Waning Crescent4Thu
5Fri2:023.72:273.28:460.78:540.75:456:33New Moon5Fri
6Sat2:333.73:123.19:300.59:270.95:436:34New Moon6Sat
7Sun3:003.73:563.110:110.49:581.05:426:35New Moon7Sun
8Mon3:223.84:413.010:500.310:291.15:406:36New Moon8Mon
9Tue3:433.85:263.011:280.311:011.25:396:37New Moon9Tue
10Wed4:093.96:132.912:040.35:376:38Waxing Crescent10Wed
11Thu4:433.97:032.912:420.35:366:39Waxing Crescent11Thu
12Fri5:233.97:562.912:201.31:250.35:346:40Waxing Crescent12Fri
13Sat6:103.88:513.01:101.42:160.45:336:40First Quarter13Sat
14Sun7:053.69:473.02:081.43:150.45:326:41First Quarter14Sun
15Mon8:103.410:393.23:161.44:160.45:306:42First Quarter15Mon
16Tue9:293.311:273.34:271.25:150.55:296:43First Quarter16Tue
17Wed10:533.25:371.06:100.55:276:44Waxing Gibbous17Wed
18Thu12:113.512:063.26:430.77:010.65:266:45Waxing Gibbous18Thu
19Fri12:513.71:113.27:450.47:500.75:256:46Waxing Gibbous19Fri
20Sat1:303.82:103.18:430.18:370.85:236:47Full Moon20Sat
21Sun2:084.03:083.19:38-0.19:230.95:226:48Full Moon21Sun
22Mon2:464.14:073.010:31-0.310:071.15:216:49Full Moon22Mon
23Tue3:264.15:063.011:22-0.410:531.25:196:50Waning Gibbous23Tue
24Wed4:064.06:053.012:12-0.45:186:51Waning Gibbous24Wed
25Thu4:503.97:043.11:01-0.45:176:52Waning Gibbous25Thu
26Fri5:373.78:013.212:301.41:52-0.35:156:53Waning Gibbous26Fri
27Sat6:303.58:563.31:271.52:44-0.25:146:53Third Quarter27Sat
28Sun7:363.29:503.42:311.53:360.05:136:54Third Quarter28Sun
29Mon8:552.910:413.53:391.54:270.15:126:55Third Quarter29Mon
30Tue10:162.811:283.64:471.35:160.35:116:56Third Quarter30Tue
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 11:32 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 Rio Vista, CA?

Rio Vista, CA is currently in a transitional phase. Tonight's moon is 37% 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 (37% 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