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 27m 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 - Mar 1930

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat8:032.98:172.91:49-0.22:07-0.36:215:36New Moon1Sat
2Sun8:342.88:502.92:20-0.22:29-0.36:195:37Waxing Crescent2Sun
3Mon9:082.79:262.92:51-0.12:55-0.36:185:38Waxing Crescent3Mon
4Tue9:462.610:062.93:24-0.13:26-0.26:165:39Waxing Crescent4Tue
5Wed10:302.410:512.94:030.14:03-0.26:155:40Waxing Crescent5Wed
6Thu11:202.311:432.84:510.24:490.06:135:42First Quarter6Thu
7Fri12:172.25:540.35:460.16:115:43First Quarter7Fri
8Sat12:432.81:222.17:330.46:540.16:105:44First Quarter8Sat
9Sun1:532.82:372.29:170.28:160.16:085:45First Quarter9Sun
10Mon3:132.93:532.410:220.09:50-0.16:065:46Waxing Gibbous10Mon
11Tue4:263.14:562.811:14-0.211:00-0.36:055:47Waxing Gibbous11Tue
12Wed5:243.35:503.112:01-0.46:035:48Waxing Gibbous12Wed
13Thu6:163.56:403.412:45-0.66:025:49Full Moon13Thu
14Fri7:033.57:273.612:51-0.71:24-0.76:005:51Full Moon14Fri
15Sat7:493.58:133.71:41-0.82:00-0.75:585:52Full Moon15Sat
16Sun8:333.38:573.72:26-0.72:33-0.65:575:53Waning Gibbous16Sun
17Mon9:173.09:423.53:10-0.53:02-0.55:555:54Waning Gibbous17Mon
18Tue10:012.710:273.23:52-0.33:32-0.25:535:55Waning Gibbous18Tue
19Wed10:472.411:152.94:380.04:050.05:525:56Waning Gibbous19Wed
20Thu11:372.25:340.34:460.35:505:57Third Quarter20Thu
21Fri12:082.612:322.06:520.55:370.55:485:58Third Quarter21Fri
22Sat1:092.31:371.88:100.66:480.75:475:59Third Quarter22Sat
23Sun2:282.22:591.89:180.69:030.75:456:00Third Quarter23Sun
24Mon3:462.24:072.010:130.510:100.55:436:01Waning Crescent24Mon
25Tue4:422.44:562.210:570.410:590.45:416:03Waning Crescent25Tue
26Wed5:232.55:352.411:340.211:410.25:406:04Waning Crescent26Wed
27Thu5:582.76:092.712:070.15:386:05Waning Crescent27Thu
28Fri6:302.86:412.912:200.012:36-0.15:366:06New Moon28Fri
29Sat7:002.97:123.112:57-0.11:01-0.25:356:07New Moon29Sat
30Sun7:332.97:463.21:32-0.21:25-0.35:336:08New Moon30Sun
31Mon8:072.88:213.32:05-0.21:52-0.35:316:09New Moon31Mon
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