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 31m at 10:17 pm (0.9 ft)
Next high tide (tomorrow) : 3:42 am (2.1 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 - Oct 1922

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun4:132.84:422.910:330.610:570.55:425:29Waxing Gibbous1Sun
2Mon5:012.95:253.011:150.511:320.45:435:28Waxing Gibbous2Mon
3Tue5:423.16:033.111:540.45:445:26Waxing Gibbous3Tue
4Wed6:193.26:383.112:020.312:290.35:455:24Full Moon4Wed
5Thu6:523.37:103.112:300.21:030.25:465:23Full Moon5Thu
6Fri7:233.37:423.112:560.11:350.25:475:21Full Moon6Fri
7Sat7:543.38:153.01:230.12:050.25:485:19Full Moon7Sat
8Sun8:263.38:502.91:520.12:340.35:495:18Waning Gibbous8Sun
9Mon9:013.29:282.82:250.23:050.45:505:16Waning Gibbous9Mon
10Tue9:403.110:122.73:000.33:410.55:515:15Waning Gibbous10Tue
11Wed10:253.011:022.63:400.44:260.65:525:13Waning Gibbous11Wed
12Thu11:173.011:572.64:270.55:240.75:545:11Third Quarter12Thu
13Fri12:153.05:250.66:460.75:555:10Third Quarter13Fri
14Sat12:582.61:173.06:340.68:210.55:565:08Third Quarter14Sat
15Sun2:032.82:253.17:540.59:220.35:575:07Waning Crescent15Sun
16Mon3:103.03:343.39:200.310:120.15:585:05Waning Crescent16Mon
17Tue4:123.44:343.510:270.010:58-0.25:595:04Waning Crescent17Tue
18Wed5:063.85:293.611:23-0.311:41-0.46:005:02Waning Crescent18Wed
19Thu5:574.16:203.812:16-0.56:015:01New Moon19Thu
20Fri6:474.37:103.812:25-0.51:08-0.66:024:59New Moon20Fri
21Sat7:364.37:593.71:08-0.51:58-0.66:044:58New Moon21Sat
22Sun8:264.28:493.51:51-0.52:48-0.46:054:56Waxing Crescent22Sun
23Mon9:164.09:403.32:34-0.33:38-0.26:064:55Waxing Crescent23Mon
24Tue10:083.710:343.03:17-0.14:350.16:074:53Waxing Crescent24Tue
25Wed11:053.411:322.84:050.25:440.36:084:52First Quarter25Wed
26Thu12:053.15:100.56:520.56:094:50First Quarter26Thu
27Fri12:342.71:082.86:570.77:540.66:114:49First Quarter27Fri
28Sat1:382.62:122.78:120.78:490.66:124:48First Quarter28Sat
29Sun2:442.63:152.69:140.79:360.56:134:46Waxing Gibbous29Sun
30Mon3:432.74:092.710:060.610:160.56:144:45Waxing Gibbous30Mon
31Tue4:322.84:542.710:490.510:510.46:154:44Waxing Gibbous31Tue
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 12:59 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