Tides Today & Tomorrow in Block Island, RI

TIDE TIMES for Friday, August 21, 2026
The tide is currently rising in Block Island, RI.
Next low tide : 7:49 am (0.9 ft)
Next high tide : in 54m at 2:30 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 - May 1924

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Thu6:532.87:133.212:590.112:510.15:437:42Waning Crescent1Thu
2Fri7:342.97:513.31:390.11:200.05:427:43New Moon2Fri
3Sat8:122.98:263.32:150.01:470.05:417:45New Moon3Sat
4Sun8:482.88:593.32:490.02:160.05:397:46New Moon4Sun
5Mon9:242.89:313.23:190.02:470.15:387:47New Moon5Mon
6Tue9:592.710:033.03:480.13:210.25:377:48Waxing Crescent6Tue
7Wed10:362.610:382.94:170.23:570.35:367:49Waxing Crescent7Wed
8Thu11:172.411:182.84:500.34:370.45:357:50Waxing Crescent8Thu
9Fri12:012.45:300.55:210.55:347:51Waxing Crescent9Fri
10Sat12:032.712:502.36:200.66:140.65:327:52First Quarter10Sat
11Sun12:542.61:422.47:220.67:160.75:317:53First Quarter11Sun
12Mon1:492.62:392.58:280.58:280.65:307:54First Quarter12Mon
13Tue2:502.63:412.79:300.49:480.55:297:55First Quarter13Tue
14Wed3:562.74:423.010:250.211:010.25:287:56Waxing Gibbous14Wed
15Thu5:002.95:373.411:130.011:59-0.15:277:57Waxing Gibbous15Thu
16Fri5:583.16:293.811:59-0.25:267:58Waxing Gibbous16Fri
17Sat6:513.37:194.012:53-0.312:45-0.45:257:59Full Moon17Sat
18Sun7:433.48:094.21:46-0.51:32-0.55:248:00Full Moon18Sun
19Mon8:353.59:004.32:38-0.62:21-0.65:248:01Full Moon19Mon
20Tue9:263.49:514.23:30-0.63:11-0.55:238:02Waning Gibbous20Tue
21Wed10:193.410:454.04:21-0.54:01-0.35:228:03Waning Gibbous21Wed
22Thu11:143.211:413.75:17-0.34:56-0.15:218:04Waning Gibbous22Thu
23Fri12:123.16:20-0.16:070.15:208:04Waning Gibbous23Fri
24Sat12:403.41:133.07:250.07:370.35:208:05Third Quarter24Sat
25Sun1:413.12:142.98:250.28:530.45:198:06Third Quarter25Sun
26Mon2:422.93:172.99:200.310:000.55:188:07Third Quarter26Mon
27Tue3:452.74:202.910:110.310:590.55:188:08Waning Crescent27Tue
28Wed4:452.65:173.010:550.311:490.45:178:09Waning Crescent28Wed
29Thu5:382.66:043.111:340.35:178:10Waning Crescent29Thu
30Fri6:242.66:463.212:330.412:070.35:168:10Waning Crescent30Fri
31Sat7:052.77:243.21:140.312:370.25:168:11New Moon31Sat
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 5:09 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