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 3h 09m 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 - Oct 2094

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri1:227.34:460.17:276.07:136:50Third Quarter1Fri
2Sat2:257.45:490.68:545.67:146:48Third Quarter2Sat
3Sun3:157.56:560.99:385.27:166:46Waning Crescent3Sun
4Mon12:515.33:547.58:001.210:044.77:176:44Waning Crescent4Mon
5Tue2:155.54:257.48:531.410:224.27:196:42Waning Crescent5Tue
6Wed3:215.84:487.39:371.710:393.77:206:40Waning Crescent6Wed
7Thu4:146.05:047.210:152.010:593.07:226:38New Moon7Thu
8Fri5:006.35:187.210:502.411:222.37:236:36New Moon8Fri
9Sat5:446.55:357.211:242.911:491.67:256:34New Moon9Sat
10Sun6:276.75:577.211:583.57:266:32New Moon10Sun
11Mon7:136.96:217.112:190.912:354.27:286:30Waxing Crescent11Mon
12Tue8:027.06:486.912:520.31:154.97:296:28Waxing Crescent12Tue
13Wed8:567.17:146.81:30-0.22:005.57:316:26Waxing Crescent13Wed
14Thu9:587.17:396.62:12-0.52:556.17:326:24Waxing Crescent14Thu
15Fri11:117.28:016.42:59-0.64:076.57:346:22First Quarter15Fri
16Sat12:287.33:53-0.55:426.67:356:20First Quarter16Sat
17Sun1:327.54:55-0.37:226.27:376:18First Quarter17Sun
18Mon2:217.66:030.08:145.57:386:16First Quarter18Mon
19Tue12:065.73:007.77:110.38:514.67:406:14Waxing Gibbous19Tue
20Wed1:385.83:337.88:130.79:283.47:416:12Waxing Gibbous20Wed
21Thu3:036.24:037.99:081.310:052.17:436:10Waxing Gibbous21Thu
22Fri4:186.64:317.99:582.010:440.97:446:09Full Moon22Fri
23Sat5:247.14:597.910:462.911:24-0.27:466:07Full Moon23Sat
24Sun6:257.45:287.811:333.87:476:05Full Moon24Sun
25Mon7:247.75:577.612:04-1.012:234.77:496:03Waning Gibbous25Mon
26Tue8:237.96:287.312:46-1.41:185.67:506:02Waning Gibbous26Tue
27Wed9:247.97:016.91:29-1.52:226.27:526:00Waning Gibbous27Wed
28Thu10:287.97:366.42:15-1.23:476.57:545:58Waning Gibbous28Thu
29Fri11:357.98:185.93:04-0.66:236.37:555:56Third Quarter29Fri
30Sat12:387.93:570.18:015.87:575:55Third Quarter30Sat
31Sun1:327.84:570.98:475.27:585:53Third Quarter31Sun
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (9449834)

Common Questions About Roche Harbor, San Juan Island, WA Tides

Show All
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