Tides Today & Tomorrow in Block Island, RI

TIDE TIMES for Monday, August 17, 2026
The tide is currently rising in Block Island, RI.
Next low tide (tomorrow) : 5:28 am (0.4 ft)
Next high tide : in 9m at 11:58 pm (2.7 ft)
Sunset today : 7:42 pm
Sunrise tomorrow : 5:58 am
Moon phase : Waxing Crescent (27% illuminated)
Tide Station Location : Station #8459338
Common Questions About Tides

Block Island, RI Tides - May 1931

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri7:323.27:584.11:38-0.51:27-0.55:447:42Full Moon1Fri
2Sat8:213.28:454.12:28-0.52:08-0.45:437:43Full Moon2Sat
3Sun9:093.19:323.93:16-0.52:49-0.35:427:44Full Moon3Sun
4Mon9:573.010:203.64:01-0.33:30-0.25:407:45Waning Gibbous4Mon
5Tue10:462.811:113.34:48-0.14:110.15:397:46Waning Gibbous5Tue
6Wed11:382.65:400.24:550.35:387:47Waning Gibbous6Wed
7Thu12:053.012:342.46:430.45:500.65:377:48Third Quarter7Thu
8Fri1:022.71:322.37:470.57:200.75:357:49Third Quarter8Fri
9Sat2:012.52:332.38:450.68:530.85:347:50Third Quarter9Sat
10Sun3:022.43:362.39:360.610:000.85:337:51Third Quarter10Sun
11Mon4:042.44:352.510:200.610:550.75:327:52Waning Crescent11Mon
12Tue4:572.45:222.710:570.511:420.55:317:53Waning Crescent12Tue
13Wed5:422.46:012.911:290.45:307:54Waning Crescent13Wed
14Thu6:202.56:343.112:240.411:59 AM0.35:297:55Waning Crescent14Thu
15Fri6:562.57:073.21:050.212:300.25:287:56Waning Crescent15Fri
16Sat7:312.67:413.41:450.11:030.15:277:57New Moon16Sat
17Sun8:092.68:183.42:230.11:390.05:267:58New Moon17Sun
18Mon8:482.78:583.43:000.12:170.05:257:59New Moon18Mon
19Tue9:292.79:403.43:340.12:580.05:248:00Waxing Crescent19Tue
20Wed10:142.710:273.34:100.23:400.15:238:01Waxing Crescent20Wed
21Thu11:032.611:173.24:510.24:270.25:238:02Waxing Crescent21Thu
22Fri11:572.65:440.35:210.35:228:03Waxing Crescent22Fri
23Sat12:133.112:562.76:510.36:280.45:218:04First Quarter23Sat
24Sun1:113.01:562.87:570.37:500.45:208:05First Quarter24Sun
25Mon2:122.92:593.08:550.29:200.45:198:06First Quarter25Mon
26Tue3:162.94:033.39:480.110:360.25:198:06Waxing Gibbous26Tue
27Wed4:222.85:043.510:390.011:390.15:188:07Waxing Gibbous27Wed
28Thu5:252.95:593.811:26-0.15:188:08Waxing Gibbous28Thu
29Fri6:212.96:503.912:34-0.112:12-0.25:178:09Waxing Gibbous29Fri
30Sat7:133.07:394.01:27-0.212:57-0.25:168:10Full Moon30Sat
31Sun8:033.08:283.92:17-0.21:43-0.15:168:11Full Moon31Sun
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 2:43 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 27% 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 Waxing Crescent (27% 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