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

TIDE TIMES for Wednesday, July 22, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 5h 06m at 6:38 am (0.8 ft)
Next high tide : 2:48 pm (5.6 ft)
Sunset today : 9:03 pm
Sunrise tomorrow : 5:34 am
Moon phase : First Quarter (63% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Jan 1989

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun1:525.010:37 AM7.93:515.46:381.58:044:27Third Quarter1Sun
2Mon3:396.011:04 AM7.85:046.57:130.68:044:28Waning Crescent2Mon
3Tue4:186.811:32 AM7.76:447.37:49-0.38:044:29Waning Crescent3Tue
4Wed4:487.512:047.78:027.88:26-1.18:044:31Waning Crescent4Wed
5Thu5:178.012:437.88:598.09:04-1.78:044:32Waning Crescent5Thu
6Fri5:458.41:307.89:438.09:45-2.28:044:33New Moon6Fri
7Sat6:138.62:267.910:247.910:26-2.58:034:34New Moon7Sat
8Sun6:428.73:267.811:087.511:09-2.48:034:35New Moon8Sun
9Mon7:118.84:287.511:587.011:52-2.08:024:36Waxing Crescent9Mon
10Tue7:408.85:327.012:546.28:024:38Waxing Crescent10Tue
11Wed8:088.86:416.412:34-1.21:545.28:014:39Waxing Crescent11Wed
12Thu8:378.87:595.71:160.12:553.98:014:40Waxing Crescent12Thu
13Fri9:068.89:365.11:591.63:552.68:004:42First Quarter13Fri
14Sat9:368.711:545.22:423.34:531.38:004:43First Quarter14Sat
15Sun10:078.53:305.05:500.27:594:45First Quarter15Sun
16Mon2:066.110:40 AM8.34:366.46:44-0.67:584:46Waxing Gibbous16Mon
17Tue3:247.111:18 AM8.16:127.47:35-1.27:574:47Waxing Gibbous17Tue
18Wed4:137.912:047.87:517.88:23-1.57:574:49Waxing Gibbous18Wed
19Thu4:538.312:587.69:117.89:07-1.67:564:50Waxing Gibbous19Thu
20Fri5:288.61:577.410:087.59:49-1.57:554:52Full Moon20Fri
21Sat6:018.62:557.210:517.110:28-1.37:544:53Full Moon21Sat
22Sun6:318.53:487.011:316.711:06-0.97:534:55Full Moon22Sun
23Mon6:588.44:396.712:126.27:524:56Full Moon23Mon
24Tue7:208.35:306.412:555.57:514:58Waning Gibbous24Tue
25Wed7:398.26:246.012:180.51:384.87:505:00Waning Gibbous25Wed
26Thu7:568.17:235.512:521.52:224.07:485:01Waning Gibbous26Thu
27Fri8:168.18:335.21:252.63:063.27:475:03Waning Gibbous27Fri
28Sat8:387.910:125.01:553.83:502.57:465:04Third Quarter28Sat
29Sun9:027.82:205.04:361.87:455:06Third Quarter29Sun
30Mon9:287.65:251.17:445:07Third Quarter30Mon
31Tue9:557.56:160.47:425:09Third Quarter31Tue
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 10:43 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 63% 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 First Quarter (63% 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