Tides Today & Tomorrow in Roche Harbor, San Juan Island, WA

TIDE TIMES for Tuesday, August 4, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 4h 18m at 2:54 pm (3.2 ft)
Next high tide : 9:37 pm (7.7 ft)
Sunset today : 8:45 pm
Sunrise tomorrow : 5:51 am
Moon phase : Third Quarter (64% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Dec 2093

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue4:517.32:427.89:145.79:50-0.97:444:19Full Moon1Tue
2Wed5:387.83:087.610:056.310:22-1.27:464:18Full Moon2Wed
3Thu6:228.23:367.310:566.610:55-1.47:474:18Full Moon3Thu
4Fri7:038.44:077.111:506.911:31-1.37:484:17Full Moon4Fri
5Sat7:448.54:406.812:496.97:494:17Waning Gibbous5Sat
6Sun8:238.45:166.512:08-1.02:006.87:504:17Waning Gibbous6Sun
7Mon9:028.45:576.112:48-0.53:356.67:514:17Waning Gibbous7Mon
8Tue9:408.36:505.61:300.05:226.17:524:16Waning Gibbous8Tue
9Wed10:158.28:005.12:130.76:145.57:534:16Third Quarter9Wed
10Thu10:498.19:254.72:591.56:424.87:544:16Third Quarter10Thu
11Fri11:208.011:024.63:482.36:584.07:554:16Third Quarter11Fri
12Sat11:508.04:433.27:173.07:564:16Third Quarter12Sat
13Sun1:004.812:208.05:434.17:401.97:574:17Waning Crescent13Sun
14Mon2:365.512:518.06:454.98:090.77:584:17Waning Crescent14Mon
15Tue3:396.31:238.17:435.68:41-0.57:584:17Waning Crescent15Tue
16Wed4:287.11:568.18:366.19:17-1.57:594:17New Moon16Wed
17Thu5:137.82:338.29:276.69:57-2.48:004:17New Moon17Thu
18Fri5:578.33:138.110:186.810:39-2.88:004:18New Moon18Fri
19Sat6:418.73:598.011:127.011:24-2.98:014:18New Moon19Sat
20Sun7:268.94:507.712:116.98:014:19Waxing Crescent20Sun
21Mon8:118.95:477.212:12-2.51:186.68:024:19Waxing Crescent21Mon
22Tue8:568.96:526.51:01-1.82:336.18:024:20Waxing Crescent22Tue
23Wed9:418.88:075.71:52-0.83:555.28:034:20First Quarter23Wed
24Thu10:248.79:415.12:440.55:144.18:034:21First Quarter24Thu
25Fri11:058.611:484.93:392.06:183.08:034:22First Quarter25Fri
26Sat11:438.44:403.47:091.88:044:22Waxing Gibbous26Sat
27Sun1:475.512:198.25:484.77:500.88:044:23Waxing Gibbous27Sun
28Mon3:086.312:528.07:005.78:250.08:044:24Waxing Gibbous28Mon
29Tue4:087.11:247.88:096.48:58-0.68:044:25Waxing Gibbous29Tue
30Wed4:567.81:567.69:116.89:30-1.08:044:26Full Moon30Wed
31Thu5:378.22:307.410:057.010:02-1.38:044:27Full Moon31Thu
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (9449834)

Common Questions About Roche Harbor, San Juan Island, WA Tides

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What time does the tide turn (slack tide) in Roche Harbor, San Juan Island, WA today?

Slack tide in Roche Harbor, San Juan Island, WA is approximately 6:15 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 Roche Harbor, San Juan Island, WA?

Roche Harbor, San Juan Island, WA is currently in a transitional phase. Tonight's moon is 64% 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 Roche Harbor, San Juan Island, WA 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 Roche Harbor, San Juan Island, WA?

Tide predictions for Roche Harbor, San Juan Island, WA 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 Roche Harbor, San Juan Island, WA?

Tide data for Roche Harbor, San Juan Island, WA is sourced from NOAA Station #9449834. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=9449834.

What is the moon phase in Roche Harbor, San Juan Island, WA tonight?

Tonight the moon over Roche Harbor, San Juan Island, WA is Third Quarter (64% illuminated). This places Roche Harbor, San Juan Island, WA 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