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

TIDE TIMES for Thursday, July 30, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 6h 54m at 12:01 pm (-1.0 ft)
Next high tide : 7:46 pm (7.7 ft)
Sunset today : 8:53 pm
Sunrise tomorrow : 5:44 am
Moon phase : Full Moon (99% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Jun 2083

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue4:137.98:118.411:56-3.85:149:07Full Moon1Tue
2Wed5:047.68:598.412:347.012:45-3.55:139:08Waning Gibbous2Wed
3Thu6:017.19:468.41:426.81:35-2.85:139:08Waning Gibbous3Thu
4Fri7:016.510:318.33:026.42:25-1.85:129:09Waning Gibbous4Fri
5Sat8:095.811:138.14:335.63:16-0.65:129:10Third Quarter5Sat
6Sun9:285.011:508.05:564.74:070.85:119:11Third Quarter6Sun
7Mon11:124.46:593.54:592.25:119:12Third Quarter7Mon
8Tue12:227.81:344.47:472.45:553.65:109:12Third Quarter8Tue
9Wed12:497.63:235.18:241.46:594.85:109:13Waning Crescent9Wed
10Thu1:117.44:386.08:550.48:095.85:109:14Waning Crescent10Thu
11Fri1:327.25:326.79:24-0.39:166.55:109:14Waning Crescent11Fri
12Sat1:557.16:157.39:52-0.910:156.95:099:15Waning Crescent12Sat
13Sun2:237.06:527.610:23-1.311:067.05:099:16New Moon13Sun
14Mon2:546.97:257.810:55-1.611:527.15:099:16New Moon14Mon
15Tue3:316.87:577.911:29-1.75:099:17New Moon15Tue
16Wed4:116.88:287.912:347.112:05-1.85:099:17New Moon16Wed
17Thu4:536.68:577.91:197.012:43-1.75:099:17Waxing Crescent17Thu
18Fri5:376.49:268.02:096.81:21-1.55:099:18Waxing Crescent18Fri
19Sat6:276.09:548.03:036.42:01-1.05:109:18Waxing Crescent19Sat
20Sun7:295.610:218.03:565.72:40-0.35:109:18Waxing Crescent20Sun
21Mon8:435.010:488.04:464.93:210.65:109:18First Quarter21Mon
22Tue10:114.511:158.05:333.74:031.95:109:19First Quarter22Tue
23Wed11:574.411:447.96:182.44:513.35:119:19First Quarter23Wed
24Thu2:134.87:030.95:494.65:119:19First Quarter24Thu
25Fri12:138.03:565.87:49-0.57:025.85:119:19Waxing Gibbous25Fri
26Sat12:468.05:006.88:35-1.88:176.75:129:19Waxing Gibbous26Sat
27Sun1:238.15:497.59:21-2.89:247.15:129:19Waxing Gibbous27Sun
28Mon2:078.06:328.010:08-3.410:267.25:139:19Full Moon28Mon
29Tue3:007.97:138.310:55-3.611:247.05:139:18Full Moon29Tue
30Wed3:597.77:528.411:42-3.45:149:18Full 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 3:53 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 99% 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 Full Moon (99% 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