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

TIDE TIMES for Thursday, July 23, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 7h 11m at 7:27 am (0.2 ft)
Next high tide : 4:07 pm (6.4 ft)
Sunset today : 9:02 pm
Sunrise tomorrow : 5:35 am
Moon phase : Waxing Gibbous (72% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Jun 2074

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri8:325.311:507.85:505.73:570.05:149:07First Quarter1Fri
2Sat10:034.86:405.04:500.75:139:08First Quarter2Sat
3Sun12:287.811:38 AM4.67:174.05:481.65:139:09First Quarter3Sun
4Mon1:037.81:204.77:542.86:502.55:129:09Waxing Gibbous4Mon
5Tue1:377.83:015.28:321.47:523.45:129:10Waxing Gibbous5Tue
6Wed2:117.94:216.09:110.08:514.25:119:11Waxing Gibbous6Wed
7Thu2:478.05:246.89:51-1.39:485.05:119:12Waxing Gibbous7Thu
8Fri3:248.06:207.510:33-2.410:435.65:109:13Full Moon8Fri
9Sat4:037.97:118.011:17-3.011:396.05:109:13Full Moon9Sat
10Sun4:467.78:018.312:02-3.25:109:14Full Moon10Sun
11Mon5:327.48:508.412:396.212:48-3.05:109:15Waning Gibbous11Mon
12Tue6:227.09:398.41:466.21:36-2.45:099:15Waning Gibbous12Tue
13Wed7:166.410:288.33:035.92:26-1.65:099:16Waning Gibbous13Wed
14Thu8:155.711:158.14:295.43:16-0.55:099:16Third Quarter14Thu
15Fri9:265.011:588.05:564.74:080.65:099:17Third Quarter15Fri
16Sat10:554.57:053.95:031.85:099:17Third Quarter16Sat
17Sun12:377.81:044.37:552.96:023.05:099:17Third Quarter17Sun
18Mon1:097.62:574.88:332.17:044.05:099:18Waning Crescent18Mon
19Tue1:367.44:135.59:031.28:074.95:109:18Waning Crescent19Tue
20Wed2:007.25:096.29:310.59:065.55:109:18Waning Crescent20Wed
21Thu2:267.15:546.79:58-0.19:586.05:109:18Waning Crescent21Thu
22Fri2:547.06:337.110:26-0.710:456.35:109:19New Moon22Fri
23Sat3:267.07:077.410:56-1.111:296.55:119:19New Moon23Sat
24Sun4:006.97:397.611:28-1.45:119:19New Moon24Sun
25Mon4:376.88:107.812:126.512:03-1.65:119:19New Moon25Mon
26Tue5:156.68:427.912:586.512:40-1.65:129:19Waxing Crescent26Tue
27Wed5:576.49:157.91:476.41:19-1.55:129:19Waxing Crescent27Wed
28Thu6:436.19:498.02:416.12:00-1.15:139:19Waxing Crescent28Thu
29Fri7:385.710:248.03:385.72:43-0.65:139:18Waxing Crescent29Fri
30Sat8:465.210:598.04:355.03:290.35:149:18First 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 11:47 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 72% 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 Waxing Gibbous (72% 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