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

TIDE TIMES for Friday, July 31, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 3h 36m at 12:35 pm (-0.7 ft)
Next high tide : 8:05 pm (7.7 ft)
Sunset today : 8:51 pm
Sunrise tomorrow : 5:46 am
Moon phase : Waning Gibbous (95% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Jan 2086

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue6:548.64:216.911:576.511:31-0.88:044:28Full Moon1Tue
2Wed7:238.55:096.612:466.18:044:29Waning Gibbous2Wed
3Thu7:498.46:006.212:09-0.11:375.68:044:30Waning Gibbous3Thu
4Fri8:138.36:545.712:460.62:295.08:044:31Waning Gibbous4Fri
5Sat8:368.27:575.21:221.63:194.38:034:32Waning Gibbous5Sat
6Sun9:018.29:134.81:582.64:083.58:034:33Third Quarter6Sun
7Mon9:288.011:174.82:333.74:562.88:034:34Third Quarter7Mon
8Tue9:597.93:094.95:422.08:024:36Third Quarter8Tue
9Wed2:175.410:32 AM7.83:565.96:271.18:024:37Third Quarter9Wed
10Thu3:286.211:08 AM7.75:286.77:090.38:014:38Waning Crescent10Thu
11Fri4:026.911:48 AM7.76:577.27:51-0.58:014:39Waning Crescent11Fri
12Sat4:317.412:347.88:037.48:32-1.28:004:41Waning Crescent12Sat
13Sun4:587.91:277.88:557.49:14-1.88:004:42New Moon13Sun
14Mon5:268.22:237.99:417.19:55-2.17:594:44New Moon14Mon
15Tue5:538.43:227.810:286.610:37-2.17:584:45New Moon15Tue
16Wed6:228.64:227.611:176.011:20-1.77:584:46New Moon16Wed
17Thu6:528.75:237.212:105.27:574:48Waxing Crescent17Thu
18Fri7:228.86:286.712:03-0.91:074.27:564:49Waxing Crescent18Fri
19Sat7:548.87:396.112:470.32:063.27:554:51Waxing Crescent19Sat
20Sun8:278.89:035.61:311.73:062.27:544:52First Quarter20Sun
21Mon9:028.610:555.42:173.24:071.37:534:54First Quarter21Mon
22Tue9:408.43:084.65:090.67:524:55First Quarter22Tue
23Wed1:005.910:20 AM8.14:135.96:100.07:514:57First Quarter23Wed
24Thu2:296.711:06 AM7.85:426.87:08-0.47:504:59Waxing Gibbous24Thu
25Fri3:287.411:59 AM7.57:197.17:59-0.77:495:00Waxing Gibbous25Fri
26Sat4:127.812:577.38:407.08:44-0.77:485:02Waxing Gibbous26Sat
27Sun4:498.11:557.19:376.89:24-0.77:465:03Full Moon27Sun
28Mon5:228.22:507.010:186.410:02-0.57:455:05Full Moon28Mon
29Tue5:518.23:406.910:546.010:37-0.27:445:06Full Moon29Tue
30Wed6:158.24:276.711:305.511:120.37:435:08Full Moon30Wed
31Thu6:368.15:146.512:074.97:415:10Waning Gibbous31Thu
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 4:20 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 spring phase. Tonight's moon is 95% 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 near their weekly maximum.

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 Waning Gibbous (95% illuminated). This places Roche Harbor, San Juan Island, WA in a spring tide cycle, so tidal ranges are near their weekly maximum 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