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 44m 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 - Dec 1923

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat12:392.612:512.76:190.57:100.36:514:18Third Quarter1Sat
2Sun1:392.81:542.77:410.48:160.16:524:18Third Quarter2Sun
3Mon2:423.03:012.89:090.29:17-0.16:534:18Waning Crescent3Mon
4Tue3:453.34:063.010:16-0.110:12-0.36:544:18Waning Crescent4Tue
5Wed4:423.65:043.111:13-0.311:02-0.56:554:17Waning Crescent5Wed
6Thu5:353.95:583.312:06-0.66:564:17New Moon6Thu
7Fri6:274.16:503.412:58-0.76:574:17New Moon7Fri
8Sat7:184.27:423.412:42-0.71:48-0.76:584:17New Moon8Sat
9Sun8:084.18:333.31:31-0.72:37-0.76:594:17Waxing Crescent9Sun
10Mon8:593.99:243.22:20-0.53:26-0.57:004:17Waxing Crescent10Mon
11Tue9:513.610:183.03:09-0.34:17-0.37:014:17Waxing Crescent11Tue
12Wed10:453.311:142.84:02-0.15:13-0.17:014:17Waxing Crescent12Wed
13Thu11:412.95:130.26:140.17:024:17First Quarter13Thu
14Fri12:132.712:372.66:400.47:100.27:034:18First Quarter14Fri
15Sat1:122.61:352.47:520.58:020.37:044:18First Quarter15Sat
16Sun2:132.52:372.38:550.58:500.37:054:18First Quarter16Sun
17Mon3:152.63:372.29:500.59:330.37:054:18Waxing Gibbous17Mon
18Tue4:092.64:282.310:380.410:130.27:064:19Waxing Gibbous18Tue
19Wed4:552.85:122.311:200.310:490.27:064:19Waxing Gibbous19Wed
20Thu5:342.95:522.412:010.17:074:19Waxing Gibbous20Thu
21Fri6:083.06:282.512:400.07:084:20Full Moon21Fri
22Sat6:413.17:042.61:17-0.17:084:20Full Moon22Sat
23Sun7:153.17:402.612:36-0.11:52-0.17:094:21Full Moon23Sun
24Mon7:493.18:172.61:13-0.12:22-0.17:094:21Full Moon24Mon
25Tue8:263.18:562.61:51-0.12:49-0.17:094:22Waning Gibbous25Tue
26Wed9:063.09:392.62:29-0.13:17-0.17:104:23Waning Gibbous26Wed
27Thu9:492.910:262.63:100.03:520.07:104:23Waning Gibbous27Thu
28Fri10:362.811:172.73:560.14:340.07:114:24Waning Gibbous28Fri
29Sat11:292.74:500.25:260.07:114:25Third Quarter29Sat
30Sun12:132.712:262.65:570.26:250.07:114:25Third Quarter30Sun
31Mon1:112.81:272.67:200.27:34-0.17:114:26Third Quarter31Mon
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (8459338)

Common Questions About Block Island, RI Tides

Show All
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