Tides Today & Tomorrow in Block Island, RI

TIDE TIMES for Tuesday, August 18, 2026
The tide is currently rising in Block Island, RI.
Next low tide : 6:49 pm (0.7 ft)
Next high tide : in 6h 38m at 12:33 pm (3.1 ft)
Sunset today : 7:41 pm
Sunrise tomorrow : 5:59 am
Moon phase : First Quarter (36% illuminated)
Tide Station Location : Station #8459338
Common Questions About Tides

Block Island, RI Tides - Oct 1930

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed2:402.33:252.78:560.99:560.85:425:29Waxing Gibbous1Wed
2Thu3:472.44:212.79:560.810:380.75:435:28Waxing Gibbous2Thu
3Fri4:382.55:042.810:420.711:140.55:445:26Waxing Gibbous3Fri
4Sat5:192.85:403.011:230.511:450.45:455:24Waxing Gibbous4Sat
5Sun5:543.06:123.012:010.45:465:23Waxing Gibbous5Sun
6Mon6:253.26:423.112:130.212:370.25:475:21Full Moon6Mon
7Tue6:553.37:143.112:380.11:130.25:485:19Full Moon7Tue
8Wed7:273.47:473.01:030.11:460.25:495:18Full Moon8Wed
9Thu8:013.58:232.91:300.12:170.25:505:16Full Moon9Thu
10Fri8:373.59:032.82:010.12:500.35:515:14Waning Gibbous10Fri
11Sat9:183.49:482.72:360.13:260.45:535:13Waning Gibbous11Sat
12Sun10:043.310:392.63:150.24:120.55:545:11Waning Gibbous12Sun
13Mon10:583.211:372.54:020.35:150.75:555:10Third Quarter13Mon
14Tue12:003.14:590.57:080.75:565:08Third Quarter14Tue
15Wed12:422.51:073.16:110.58:280.65:575:07Third Quarter15Wed
16Thu1:512.62:203.17:420.59:270.45:585:05Third Quarter16Thu
17Fri3:022.93:313.29:160.310:170.15:595:03Waning Crescent17Fri
18Sat4:063.24:313.410:230.111:00-0.16:005:02Waning Crescent18Sat
19Sun5:013.65:233.511:19-0.111:40-0.36:015:00Waning Crescent19Sun
20Mon5:503.96:113.512:10-0.36:034:59New Moon20Mon
21Tue6:374.16:583.512:18-0.412:59-0.46:044:57New Moon21Tue
22Wed7:234.17:443.412:54-0.41:46-0.36:054:56New Moon22Wed
23Thu8:084.08:293.21:30-0.32:30-0.26:064:55Waxing Crescent23Thu
24Fri8:523.89:143.02:04-0.13:120.06:074:53Waxing Crescent24Fri
25Sat9:383.510:022.72:400.13:550.36:084:52Waxing Crescent25Sat
26Sun10:283.210:542.53:170.34:490.56:094:50Waxing Crescent26Sun
27Mon11:232.911:522.34:000.66:070.76:114:49First Quarter27Mon
28Tue12:252.64:540.87:200.86:124:48First Quarter28Tue
29Wed12:552.21:312.56:260.98:200.86:134:46First Quarter29Wed
30Thu2:032.22:392.58:210.99:120.76:144:45First Quarter30Thu
31Fri3:092.33:372.59:240.89:530.66:154:44Waxing Gibbous31Fri
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 3:41 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 transitional phase. Tonight's moon is 36% 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 (36% 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