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

TIDE TIMES for Tuesday, August 4, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide (tomorrow) : 4:34 am (1.0 ft)
Next high tide : in 53m at 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 - Jan 2095

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat3:015.511:55 AM7.85:575.87:410.98:044:28Waning Crescent1Sat
2Sun3:576.412:257.87:086.58:12-0.18:044:29Waning Crescent2Sun
3Mon4:387.212:577.88:107.18:46-1.08:044:30Waning Crescent3Mon
4Tue5:137.81:317.89:047.49:23-1.88:044:31New Moon4Tue
5Wed5:478.32:117.99:517.610:02-2.48:034:32New Moon5Wed
6Thu6:218.62:587.910:387.610:44-2.78:034:33New Moon6Thu
7Fri6:568.83:517.811:277.411:29-2.68:034:34New Moon7Fri
8Sat7:328.94:497.512:227.08:024:35Waxing Crescent8Sat
9Sun8:088.95:527.012:15-2.21:236.48:024:37Waxing Crescent9Sun
10Mon8:448.87:016.31:01-1.42:295.68:024:38Waxing Crescent10Mon
11Tue9:208.88:215.61:48-0.23:374.58:014:39First Quarter11Tue
12Wed9:548.710:015.02:361.24:433.28:004:41First Quarter12Wed
13Thu10:298.63:262.85:431.98:004:42First Quarter13Thu
14Fri12:175.111:03 AM8.44:234.46:370.77:594:43First Quarter14Fri
15Sat2:135.911:39 AM8.25:355.87:25-0.27:584:45Waxing Gibbous15Sat
16Sun3:296.912:178.06:586.78:09-0.97:584:46Waxing Gibbous16Sun
17Mon4:227.712:577.88:187.28:49-1.47:574:48Waxing Gibbous17Mon
18Tue5:058.21:417.59:257.39:28-1.57:564:49Full Moon18Tue
19Wed5:438.52:287.410:207.310:07-1.57:554:51Full Moon19Wed
20Thu6:188.63:167.211:077.110:45-1.37:544:52Full Moon20Thu
21Fri6:518.54:037.011:506.811:23-0.97:534:54Full Moon21Fri
22Sat7:208.44:516.712:336.47:524:55Waning Gibbous22Sat
23Sun7:468.35:396.412:01-0.41:195.97:514:57Waning Gibbous23Sun
24Mon8:098.26:306.012:380.32:065.47:504:58Waning Gibbous24Mon
25Tue8:318.17:285.51:151.12:544.77:495:00Waning Gibbous25Tue
26Wed8:558.08:365.11:502.13:424.07:485:01Third Quarter26Wed
27Thu9:207.910:064.82:253.24:293.27:475:03Third Quarter27Thu
28Fri9:487.73:004.35:152.37:455:05Third Quarter28Fri
29Sat1:065.110:18 AM7.63:425.56:011.47:445:06Third Quarter29Sat
30Sun3:035.910:50 AM7.55:016.56:460.57:435:08Waning Crescent30Sun
31Mon3:486.711:27 AM7.56:397.17:31-0.37:425:09Waning Crescent31Mon
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 1:05 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 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