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

TIDE TIMES for Wednesday, July 22, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 5:41 pm (5.8 ft)
Next high tide : in 8h 01m at 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 - Sep 1988

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Thu10:186.28:467.53:06-0.22:574.86:307:54Third Quarter1Thu
2Fri12:026.34:01-0.54:025.96:317:52Third Quarter2Fri
3Sat1:426.75:00-0.55:386.66:337:50Third Quarter3Sat
4Sun2:567.16:04-0.48:156.76:347:48Third Quarter4Sun
5Mon3:497.47:12-0.29:406.36:367:46Waning Crescent5Mon
6Tue12:126.04:307.58:170.010:175.96:377:43Waning Crescent6Tue
7Wed1:346.05:047.59:110.110:395.56:387:41Waning Crescent7Wed
8Thu2:466.15:327.49:550.310:565.06:407:39Waning Crescent8Thu
9Fri3:456.25:537.310:310.611:164.46:417:37New Moon9Fri
10Sat4:356.36:077.211:041.011:413.76:437:35New Moon10Sat
11Sun5:226.36:187.111:361.56:447:33New Moon11Sun
12Mon6:096.36:317.112:082.912:072.26:457:31New Moon12Mon
13Tue6:576.36:497.112:382.112:393.06:477:29Waxing Crescent13Tue
14Wed7:476.37:117.01:111.41:133.96:487:27Waxing Crescent14Wed
15Thu8:436.37:336.91:450.81:494.86:507:25Waxing Crescent15Thu
16Fri9:486.37:546.72:240.32:295.66:517:22Waxing Crescent16Fri
17Sat11:156.38:086.63:080.03:186.36:527:20First Quarter17Sat
18Sun1:106.53:59-0.24:356.96:547:18First Quarter18Sun
19Mon2:306.95:00-0.36:347.16:557:16First Quarter19Mon
20Tue3:157.16:08-0.48:066.86:577:14First Quarter20Tue
21Wed3:487.37:17-0.58:466.26:587:12Waxing Gibbous21Wed
22Thu12:416.34:147.58:18-0.59:225.37:007:10Waxing Gibbous22Thu
23Fri2:086.54:387.69:12-0.410:004.17:017:08Waxing Gibbous23Fri
24Sat3:266.75:017.79:590.110:402.77:027:05Full Moon24Sat
25Sun4:386.95:247.810:440.911:211.37:047:03Full Moon25Sun
26Mon5:467.15:487.811:282.07:057:01Full Moon26Mon
27Tue6:527.26:147.812:040.112:123.37:076:59Waning Gibbous27Tue
28Wed7:587.36:427.712:49-0.91:004.57:086:57Waning Gibbous28Wed
29Thu9:087.37:127.41:35-1.41:535.57:106:55Waning Gibbous29Thu
30Fri10:257.37:447.02:23-1.42:596.37:116:53Waning Gibbous30Fri
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 4:14 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 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