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

TIDE TIMES for Friday, July 17, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 1:31 pm (-1.3 ft)
Next high tide : in 2h 34m at 6:35 am (6.6 ft)
Sunset today : 9:08 pm
Sunrise tomorrow : 5:28 am
Moon phase : Waxing Crescent (15% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Jun 1990

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri12:347.81:064.47:572.95:593.05:149:06First Quarter1Fri
2Sat1:027.63:024.98:331.87:014.35:139:07Waxing Gibbous2Sat
3Sun1:257.44:225.79:020.88:065.35:139:08Waxing Gibbous3Sun
4Mon1:457.25:206.59:280.09:086.15:129:09Waxing Gibbous4Mon
5Tue2:067.16:067.19:54-0.610:066.65:129:10Waxing Gibbous5Tue
6Wed2:317.06:467.510:22-1.210:576.95:119:10Full Moon6Wed
7Thu3:007.07:217.810:52-1.511:447.05:119:11Full Moon7Thu
8Fri3:336.97:557.911:25-1.75:109:12Full Moon8Fri
9Sat4:096.88:287.912:307.012:00-1.85:109:13Full Moon9Sat
10Sun4:486.79:007.91:177.012:38-1.75:109:13Waning Gibbous10Sun
11Mon5:296.59:327.92:096.91:17-1.65:099:14Waning Gibbous11Mon
12Tue6:146.210:038.03:066.61:58-1.25:099:15Waning Gibbous12Tue
13Wed7:125.710:328.04:036.12:38-0.65:099:15Waning Gibbous13Wed
14Thu8:255.211:007.94:555.33:200.25:099:16Third Quarter14Thu
15Fri9:514.711:277.95:414.24:041.35:099:16Third Quarter15Fri
16Sat11:314.411:557.96:252.94:512.75:099:17Third Quarter16Sat
17Sun1:354.67:081.55:484.15:099:17Third Quarter17Sun
18Mon12:247.93:325.57:510.06:555.35:099:17Waning Crescent18Mon
19Tue12:548.04:466.58:35-1.48:076.35:099:18Waning Crescent19Tue
20Wed1:288.05:407.39:19-2.69:156.95:099:18Waning Crescent20Wed
21Thu2:088.16:267.910:05-3.310:167.25:109:18New Moon21Thu
22Fri2:558.07:098.210:51-3.711:157.15:109:18New Moon22Fri
23Sat3:507.87:518.411:38-3.65:109:19New Moon23Sat
24Sun4:497.58:318.412:156.912:26-3.25:109:19Waxing Crescent24Sun
25Mon5:507.09:108.31:216.51:13-2.45:119:19Waxing Crescent25Mon
26Tue6:526.49:468.22:325.92:00-1.45:119:19Waxing Crescent26Tue
27Wed7:585.610:208.13:475.02:46-0.15:129:19Waxing Crescent27Wed
28Thu9:144.910:507.94:574.13:311.35:129:19First Quarter28Thu
29Fri10:554.411:167.75:573.04:172.75:139:18First Quarter29Fri
30Sat1:204.56:482.05:084.25:139:18First Quarter30Sat
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 10:03 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 spring phase. Tonight's moon is 15% 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 Waxing Crescent (15% 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