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

TIDE TIMES for Monday, August 3, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 2:18 pm (1.9 ft)
Next high tide : in 30m at 8:27 am (5.4 ft)
Sunset today : 8:47 pm
Sunrise tomorrow : 5:50 am
Moon phase : Waning Gibbous (74% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Sep 1970

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue5:186.36:417.211:460.96:297:55New Moon1Tue
2Wed6:056.36:557.212:223.512:171.66:317:53New Moon2Wed
3Thu6:546.27:137.212:542.712:492.46:327:51Waxing Crescent3Thu
4Fri7:466.17:357.21:282.01:223.36:337:49Waxing Crescent4Fri
5Sat8:446.07:587.02:041.31:564.36:357:47Waxing Crescent5Sat
6Sun9:525.98:216.92:440.72:345.26:367:45Waxing Crescent6Sun
7Mon11:256.08:426.83:300.23:176.06:387:43First Quarter7Mon
8Tue1:346.34:22-0.14:246.76:397:41First Quarter8Tue
9Wed2:556.75:24-0.36:137.16:407:39First Quarter9Wed
10Thu3:397.16:32-0.67:486.96:427:36Waxing Gibbous10Thu
11Fri4:117.37:38-0.88:456.46:437:34Waxing Gibbous11Fri
12Sat12:546.64:387.48:38-1.09:295.66:457:32Waxing Gibbous12Sat
13Sun2:176.85:037.69:30-0.910:114.56:467:30Waxing Gibbous13Sun
14Mon3:336.95:267.710:17-0.510:543.26:477:28Full Moon14Mon
15Tue4:447.05:507.811:010.311:381.96:497:26Full Moon15Tue
16Wed5:527.16:157.811:441.46:507:24Full Moon16Wed
17Thu6:587.06:417.812:220.712:282.76:527:22Waning Gibbous17Thu
18Fri8:057.07:087.61:08-0.21:153.96:537:20Waning Gibbous18Fri
19Sat9:186.97:387.41:55-0.82:075.16:547:17Waning Gibbous19Sat
20Sun10:406.98:107.02:45-0.93:106.06:567:15Third Quarter20Sun
21Mon12:097.03:37-0.74:386.66:577:13Third Quarter21Mon
22Tue1:317.24:36-0.37:256.66:597:11Third Quarter22Tue
23Wed2:347.45:420.28:596.17:007:09Third Quarter23Wed
24Thu3:227.46:530.69:385.77:017:07Waning Crescent24Thu
25Fri12:195.54:007.47:590.910:025.17:037:05Waning Crescent25Fri
26Sat1:495.64:297.38:531.110:194.67:047:03Waning Crescent26Sat
27Sun3:025.84:507.29:361.410:363.97:067:00Waning Crescent27Sun
28Mon4:006.05:037.110:121.810:553.17:076:58New Moon28Mon
29Tue4:516.25:137.110:442.311:182.37:096:56New Moon29Tue
30Wed5:386.45:257.111:163.011:441.57:106:54New Moon30Wed
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 11:22 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 74% 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 Waning Gibbous (74% 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