Tides Today & Tomorrow in Block Island, RI

TIDE TIMES for Thursday, August 20, 2026
The tide is currently falling in Block Island, RI.
Next low tide : in 3h 14m at 9:10 pm (0.9 ft)
Next high tide (tomorrow) : 2:30 am (2.1 ft)
Sunset today : 7:38 pm
Sunrise tomorrow : 6:01 am
Moon phase : First Quarter (55% illuminated)
Tide Station Location : Station #8459338
Common Questions About Tides

Block Island, RI Tides - Aug 1924

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri8:433.08:543.42:560.22:250.15:418:03New Moon1Fri
2Sat9:223.19:323.43:240.13:040.15:428:02New Moon2Sat
3Sun10:033.110:133.33:490.13:440.25:438:01Waxing Crescent3Sun
4Mon10:463.210:573.24:170.14:270.25:448:00Waxing Crescent4Mon
5Tue11:333.211:453.14:510.15:150.35:457:58Waxing Crescent5Tue
6Wed12:233.35:330.16:120.45:467:57First Quarter6Wed
7Thu12:383.01:183.36:230.27:240.55:477:56First Quarter7Thu
8Fri1:352.92:163.47:200.28:520.55:487:55First Quarter8Fri
9Sat2:372.83:213.48:250.210:140.45:497:53First Quarter9Sat
10Sun3:462.84:303.59:390.211:190.25:507:52Waxing Gibbous10Sun
11Mon4:562.95:353.710:570.15:517:51Waxing Gibbous11Mon
12Tue5:593.16:323.912:160.012:03-0.15:527:49Waxing Gibbous12Tue
13Wed6:553.37:254.01:07-0.11:01-0.25:537:48Full Moon13Wed
14Thu7:473.58:154.01:56-0.31:55-0.35:547:47Full Moon14Thu
15Fri8:363.69:023.92:40-0.32:45-0.25:557:45Full Moon15Fri
16Sat9:243.69:473.73:21-0.33:31-0.15:567:44Waning Gibbous16Sat
17Sun10:103.610:323.53:57-0.24:140.05:577:43Waning Gibbous17Sun
18Mon10:563.411:163.24:300.04:560.25:587:41Waning Gibbous18Mon
19Tue11:423.25:000.25:430.55:597:40Waning Gibbous19Tue
20Wed12:022.912:283.05:320.36:450.76:007:38Third Quarter20Wed
21Thu12:492.71:162.96:110.57:570.86:017:37Third Quarter21Thu
22Fri1:382.52:052.76:580.79:050.96:027:35Third Quarter22Fri
23Sat2:312.33:012.77:530.710:080.96:037:34Third Quarter23Sat
24Sun3:352.34:112.78:560.811:030.86:047:32Waning Crescent24Sun
25Mon4:422.35:122.810:090.711:500.76:057:31Waning Crescent25Mon
26Tue5:352.55:582.911:110.66:067:29Waning Crescent26Tue
27Wed6:182.66:363.112:330.512:010.46:077:27Waning Crescent27Wed
28Thu6:572.97:123.31:120.412:450.36:087:26New Moon28Thu
29Fri7:353.17:493.41:470.21:270.16:097:24New Moon29Fri
30Sat8:143.38:283.52:180.12:090.06:107:23New Moon30Sat
31Sun8:543.49:083.52:460.02:490.06:117:21New Moon31Sun
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (8459338)

Common Questions About Block Island, RI Tides

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What time does the tide turn (slack tide) in Block Island, RI today?

Slack tide in Block Island, RI is approximately 11:50 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 Block Island, RI?

Block Island, RI is currently in a neap phase. Tonight's moon is 55% 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 Block Island, RI 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 Block Island, RI?

Tide predictions for Block Island, RI 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 Block Island, RI?

Tide data for Block Island, RI is sourced from NOAA Station #8459338. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=8459338.

What is the moon phase in Block Island, RI tonight?

Tonight the moon over Block Island, RI is First Quarter (55% illuminated). This places Block Island, RI 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