Tides Today & Tomorrow in Block Island, RI

TIDE TIMES for Friday, August 21, 2026
The tide is currently falling in Block Island, RI.
Next low tide : in 1h 30m at 7:49 am (0.9 ft)
Next high tide : 3:23 pm (2.6 ft)
Sunset today : 7:36 pm
Sunrise tomorrow : 6:02 am
Moon phase : First Quarter (65% illuminated)
Tide Station Location : Station #8459338
Common Questions About Tides

Block Island, RI Tides - Jan 1924

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue2:173.02:372.68:560.18:43-0.27:114:27Waning Crescent1Tue
2Wed3:233.23:472.710:07-0.19:50-0.37:114:28Waning Crescent2Wed
3Thu4:263.44:492.811:05-0.410:49-0.57:124:29Waning Crescent3Thu
4Fri5:223.75:453.011:59-0.511:43-0.67:124:29Waning Crescent4Fri
5Sat6:153.86:383.112:50-0.77:124:30New Moon5Sat
6Sun7:063.97:293.212:35-0.71:38-0.77:124:31New Moon6Sun
7Mon7:553.88:183.21:25-0.72:23-0.77:124:32New Moon7Mon
8Tue8:433.69:063.12:13-0.63:06-0.67:114:33Waxing Crescent8Tue
9Wed9:303.49:553.02:57-0.43:47-0.47:114:34Waxing Crescent9Wed
10Thu10:183.110:452.83:42-0.24:27-0.27:114:35Waxing Crescent10Thu
11Fri11:062.811:362.64:300.05:080.07:114:36Waxing Crescent11Fri
12Sat11:562.55:350.35:500.17:114:37First Quarter12Sat
13Sun12:282.512:462.26:560.46:350.27:104:38First Quarter13Sun
14Mon1:222.41:412.08:060.57:240.37:104:40First Quarter14Mon
15Tue2:212.32:441.99:100.58:200.37:104:41First Quarter15Tue
16Wed3:262.33:492.010:060.49:200.37:094:42Waxing Gibbous16Wed
17Thu4:212.44:412.010:540.310:120.27:094:43Waxing Gibbous17Thu
18Fri5:052.65:242.211:380.110:580.17:084:44Waxing Gibbous18Fri
19Sat5:432.86:032.312:200.07:084:45Waxing Gibbous19Sat
20Sun6:182.96:402.512:59-0.17:074:46Full Moon20Sun
21Mon6:543.07:172.612:20-0.21:34-0.27:074:48Full Moon21Mon
22Tue7:313.17:562.712:59-0.32:05-0.37:064:49Full Moon22Tue
23Wed8:093.28:362.81:39-0.42:32-0.37:054:50Full Moon23Wed
24Thu8:493.19:192.92:18-0.43:00-0.47:054:51Waning Gibbous24Thu
25Fri9:333.010:052.93:00-0.33:32-0.37:044:52Waning Gibbous25Fri
26Sat10:202.910:562.93:45-0.24:12-0.37:034:54Waning Gibbous26Sat
27Sun11:112.711:502.94:38-0.14:59-0.27:024:55Third Quarter27Sun
28Mon12:072.65:430.05:54-0.27:014:56Third Quarter28Mon
29Tue12:492.91:082.57:100.16:58-0.17:014:57Third Quarter29Tue
30Wed1:532.92:162.48:450.08:15-0.17:004:59Third Quarter30Wed
31Thu3:033.03:302.49:57-0.19:39-0.26:595:00Waning Crescent31Thu
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 11:36 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 Block Island, RI?

Block Island, RI is currently in a transitional phase. Tonight's moon is 65% 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 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 (65% illuminated). This places Block Island, RI 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