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

TIDE TIMES for Friday, August 7, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 6h 23m at 6:26 am (-0.8 ft)
Next high tide : 3:31 pm (6.2 ft)
Sunset today : 8:41 pm
Sunrise tomorrow : 5:55 am
Moon phase : Third Quarter (31% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Sep 2099

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue6:076.37:097.212:303.612:241.56:307:54Full Moon1Tue
2Wed6:566.27:247.21:042.912:562.36:327:51Waning Gibbous2Wed
3Thu7:486.07:447.11:392.21:293.26:337:49Waning Gibbous3Thu
4Fri8:455.98:066.92:151.62:044.26:357:47Waning Gibbous4Fri
5Sat9:535.88:286.82:541.02:415.16:367:45Waning Gibbous5Sat
6Sun11:275.98:486.63:370.63:236.06:377:43Third Quarter6Sun
7Mon1:486.24:270.34:326.76:397:41Third Quarter7Mon
8Tue3:096.65:260.16:387.06:407:39Third Quarter8Tue
9Wed3:507.06:31-0.28:207.06:427:37Waning Crescent9Wed
10Thu4:197.27:36-0.58:576.76:437:35Waning Crescent10Thu
11Fri12:386.54:447.48:34-0.89:306.06:447:33Waning Crescent11Fri
12Sat2:006.75:067.59:26-1.010:065.16:467:31Waning Crescent12Sat
13Sun3:156.95:287.610:12-0.810:463.96:477:29New Moon13Sun
14Mon4:257.05:517.710:56-0.211:282.66:497:26New Moon14Mon
15Tue5:327.16:157.811:380.86:507:24New Moon15Tue
16Wed6:397.16:407.912:131.312:222.06:517:22Waxing Crescent16Wed
17Thu7:477.07:087.81:000.11:073.46:537:20Waxing Crescent17Thu
18Fri9:006.97:387.61:48-0.71:574.76:547:18Waxing Crescent18Fri
19Sat10:236.98:107.32:39-1.12:555.76:567:16First Quarter19Sat
20Sun11:567.08:476.93:33-1.14:146.56:577:14First Quarter20Sun
21Mon1:227.34:32-0.86:176.76:587:12First Quarter21Mon
22Tue2:307.55:38-0.38:436.47:007:09First Quarter22Tue
23Wed3:217.66:500.29:345.87:017:07Waxing Gibbous23Wed
24Thu12:165.74:017.67:590.510:045.27:037:05Waxing Gibbous24Thu
25Fri1:485.74:347.58:560.810:254.77:047:03Waxing Gibbous25Fri
26Sat3:055.85:007.49:411.110:434.07:057:01Waxing Gibbous26Sat
27Sun4:056.05:187.310:181.611:043.37:076:59Full Moon27Sun
28Mon4:566.25:307.110:512.211:272.57:086:57Full Moon28Mon
29Tue5:436.45:407.111:232.811:531.77:106:55Full Moon29Tue
30Wed6:296.55:547.111:563.67:116:53Full 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 10:58 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 31% 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 (31% 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