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 1m 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 2073

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri3:597.06:017.510:46-0.811:143.96:317:53New Moon1Fri
2Sat4:577.16:317.711:30-0.611:583.16:327:51New Moon2Sat
3Sun5:567.17:027.812:130.06:347:49Waxing Crescent3Sun
4Mon6:567.07:367.812:462.212:590.96:357:47Waxing Crescent4Mon
5Tue8:006.78:117.71:371.41:472.06:367:45Waxing Crescent5Tue
6Wed9:106.58:497.52:300.82:383.16:387:43Waxing Crescent6Wed
7Thu10:326.39:317.33:270.33:374.26:397:41First Quarter7Thu
8Fri12:096.34:280.14:495.16:417:38First Quarter8Fri
9Sat1:396.65:320.06:175.66:427:36First Quarter9Sat
10Sun2:497.06:390.17:525.66:437:34Waxing Gibbous10Sun
11Mon12:216.33:437.37:440.29:075.36:457:32Waxing Gibbous11Mon
12Tue1:356.24:277.58:420.39:554.96:467:30Waxing Gibbous12Tue
13Wed2:456.25:037.59:310.410:304.46:487:28Waxing Gibbous13Wed
14Thu3:466.35:347.410:140.711:003.96:497:26Full Moon14Thu
15Fri4:376.45:597.310:521.011:293.46:507:24Full Moon15Fri
16Sat5:236.56:197.211:281.56:527:22Full Moon16Sat
17Sun6:066.56:377.112:002.912:042.06:537:19Full Moon17Sun
18Mon6:496.56:587.012:322.412:412.66:557:17Waning Gibbous18Mon
19Tue7:336.57:226.91:071.91:193.36:567:15Waning Gibbous19Tue
20Wed8:226.47:516.71:441.52:004.06:577:13Waning Gibbous20Wed
21Thu9:156.38:226.52:231.32:454.76:597:11Waning Gibbous21Thu
22Fri10:186.38:576.33:061.13:395.37:007:09Third Quarter22Fri
23Sat11:366.39:376.13:541.04:485.77:027:07Third Quarter23Sat
24Sun1:066.44:480.96:145.97:037:05Third Quarter24Sun
25Mon2:136.75:480.87:325.87:047:02Third Quarter25Mon
26Tue2:596.96:510.78:235.57:067:00Waning Crescent26Tue
27Wed12:435.93:347.17:510.59:004.97:076:58Waning Crescent27Wed
28Thu1:546.14:057.38:450.49:364.17:096:56Waning Crescent28Thu
29Fri3:036.54:347.59:340.410:133.17:106:54Waning Crescent29Fri
30Sat4:086.85:047.610:200.710:532.07:126:52New Moon30Sat
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