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

TIDE TIMES for Friday, July 31, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 2h 09m at 12:53 am (5.6 ft)
Next high tide : 5:34 am (6.5 ft)
Sunset today : 8:53 pm
Sunrise tomorrow : 5:44 am
Moon phase : Full Moon (99% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Mar 2085

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Thu7:397.810:326.41:474.82:470.26:515:57First Quarter1Thu
2Fri8:147.42:455.73:430.36:495:59First Quarter2Fri
3Sat12:126.58:54 AM6.94:036.44:450.56:476:00First Quarter3Sat
4Sun1:336.99:45 AM6.55:536.75:510.76:456:02First Quarter4Sun
5Mon2:317.210:51 AM6.27:546.46:550.86:436:03Waxing Gibbous5Mon
6Tue3:137.312:086.18:496.17:500.96:416:05Waxing Gibbous6Tue
7Wed3:467.41:236.19:175.68:351.06:396:06Waxing Gibbous7Wed
8Thu4:127.42:266.29:385.19:121.16:376:08Waxing Gibbous8Thu
9Fri4:317.33:196.49:594.49:451.46:356:09Full Moon9Fri
10Sat4:447.34:086.510:243.710:171.86:336:11Full Moon10Sat
11Sun5:577.45:556.511:512.911:492.47:317:12Full Moon11Sun
12Mon6:147.56:426.612:212.17:297:14Full Moon12Mon
13Tue6:367.57:316.612:223.012:541.47:277:15Waning Gibbous13Tue
14Wed7:017.58:246.612:563.81:300.77:257:17Waning Gibbous14Wed
15Thu7:287.49:256.51:334.52:110.27:237:19Waning Gibbous15Thu
16Fri7:567.310:386.52:135.32:57-0.27:217:20Waning Gibbous16Fri
17Sat8:267.22:596.03:50-0.47:197:22Third Quarter17Sat
18Sun12:106.59:01 AM7.04:006.54:50-0.47:177:23Third Quarter18Sun
19Mon1:396.79:56 AM6.85:286.75:56-0.47:147:25Third Quarter19Mon
20Tue2:387.011:18 AM6.57:046.57:04-0.37:127:26Waning Crescent20Tue
21Wed3:197.312:486.48:185.88:06-0.17:107:28Waning Crescent21Wed
22Thu3:537.52:166.49:104.89:020.27:087:29Waning Crescent22Thu
23Fri4:227.63:376.69:553.69:520.87:067:31Waning Crescent23Fri
24Sat4:497.84:486.910:372.310:381.57:047:32New Moon24Sat
25Sun5:157.95:527.111:191.111:232.47:027:34New Moon25Sun
26Mon5:427.96:537.212:000.17:007:35New Moon26Mon
27Tue6:107.87:517.312:083.412:43-0.56:587:36Waxing Crescent27Tue
28Wed6:407.78:527.212:554.31:26-0.96:567:38Waxing Crescent28Wed
29Thu7:127.49:577.11:465.12:12-0.86:547:39Waxing Crescent29Thu
30Fri7:477.011:107.02:445.73:00-0.56:527:41Waxing Crescent30Fri
31Sat8:256.63:546.13:520.06:497:42First Quarter31Sat
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 3:13 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 99% 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 Full Moon (99% 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