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

TIDE TIMES for Saturday, August 1, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 5h 10m at 1:08 pm (-0.1 ft)
Next high tide : 8:25 pm (7.8 ft)
Sunset today : 8:50 pm
Sunrise tomorrow : 5:47 am
Moon phase : Waning Gibbous (90% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Mar 1974

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri12:086.09:36 AM7.43:476.15:15-0.17:546:55First Quarter1Fri
2Sat1:596.410:23 AM7.35:056.76:21-0.47:526:57First Quarter2Sat
3Sun3:076.811:30 AM7.16:466.87:26-0.67:506:59Waxing Gibbous3Sun
4Mon3:517.212:507.08:116.58:27-0.77:487:00Waxing Gibbous4Mon
5Tue4:267.52:127.09:145.89:21-0.67:467:02Waxing Gibbous5Tue
6Wed4:567.83:297.010:044.810:10-0.37:447:03Full Moon6Wed
7Thu5:257.94:387.110:503.710:550.37:427:05Full Moon7Thu
8Fri5:528.05:427.111:342.611:381.17:407:06Full Moon8Fri
9Sat6:198.16:437.112:181.77:387:08Full Moon9Sat
10Sun6:478.17:436.912:222.11:020.97:367:09Waning Gibbous10Sun
11Mon7:157.98:456.81:063.21:470.47:337:11Waning Gibbous11Mon
12Tue7:457.79:556.61:534.22:340.27:317:12Waning Gibbous12Tue
13Wed8:177.411:166.52:455.13:220.27:297:14Waning Gibbous13Wed
14Thu8:537.03:465.84:150.57:277:15Third Quarter14Thu
15Fri12:466.69:33 AM6.65:036.25:140.87:257:17Third Quarter15Fri
16Sat2:036.810:25 AM6.36:446.36:191.17:237:18Third Quarter16Sat
17Sun3:027.011:32 AM6.08:266.17:251.37:217:20Third Quarter17Sun
18Mon3:447.112:495.89:195.78:221.47:197:21Waning Crescent18Mon
19Tue4:167.12:065.99:505.29:101.57:177:23Waning Crescent19Tue
20Wed4:407.13:136.010:134.69:491.67:157:24Waning Crescent20Wed
21Thu4:577.14:106.210:363.810:241.97:137:26Waning Crescent21Thu
22Fri5:107.25:016.411:013.010:572.37:117:27New Moon22Fri
23Sat5:267.35:496.611:302.211:312.87:087:29New Moon23Sat
24Sun5:477.46:386.812:011.37:067:30New Moon24Sun
25Mon6:127.47:286.912:063.512:360.57:047:32Waxing Crescent25Mon
26Tue6:397.48:226.912:434.11:15-0.27:027:33Waxing Crescent26Tue
27Wed7:097.39:226.91:234.81:58-0.67:007:35Waxing Crescent27Wed
28Thu7:407.210:326.82:095.52:47-0.96:587:36Waxing Crescent28Thu
29Fri8:167.111:526.83:026.03:41-0.86:567:38First Quarter29Fri
30Sat9:016.84:126.44:42-0.66:547:39First Quarter30Sat
31Sun1:097.010:08 AM6.45:426.45:48-0.36:527:41First Quarter31Sun
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 4:46 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 90% 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 (90% 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