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

TIDE TIMES for Thursday, July 9, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 5:57 pm (5.8 ft)
Next high tide : in 1h 52m at 3:25 pm (5.5 ft)
Sunset today : 9:15 pm
Sunrise tomorrow : 5:20 am
Moon phase : Waning Crescent (28% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Aug 1999

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun7:336.09:157.82:234.42:020.25:468:51Waning Gibbous1Sun
2Mon8:355.69:487.83:153.62:441.15:488:49Waning Gibbous2Mon
3Tue9:485.210:227.74:092.73:302.25:498:48Third Quarter3Tue
4Wed11:185.011:007.65:061.84:223.45:508:46Third Quarter4Wed
5Thu1:135.26:040.85:254.65:528:45Third Quarter5Thu
6Fri2:565.87:02-0.16:415.45:538:43Waning Crescent6Fri
7Sat12:267.54:046.57:58-0.97:595.95:548:41Waning Crescent7Sat
8Sun1:187.44:557.18:51-1.59:086.05:568:40Waning Crescent8Sun
9Mon2:157.45:387.59:41-1.910:065.85:578:38New Moon9Mon
10Tue3:137.36:167.810:28-2.010:585.45:588:36New Moon10Tue
11Wed4:127.26:527.911:13-1.811:475.06:008:35New Moon11Wed
12Thu5:087.07:267.911:56-1.36:018:33New Moon12Thu
13Fri6:036.87:587.812:374.512:40-0.66:038:31Waxing Crescent13Fri
14Sat6:576.48:287.71:274.01:230.36:048:30Waxing Crescent14Sat
15Sun7:546.08:577.52:183.42:071.36:058:28Waxing Crescent15Sun
16Mon8:555.69:267.33:102.92:522.46:078:26Waxing Crescent16Mon
17Tue10:115.39:567.14:022.43:413.56:088:24First Quarter17Tue
18Wed11:585.210:306.84:562.04:384.56:108:22First Quarter18Wed
19Thu1:525.55:511.65:495.36:118:21First Quarter19Thu
20Fri3:116.06:461.37:125.86:128:19First Quarter20Fri
21Sat4:056.57:390.98:295.96:148:17Waxing Gibbous21Sat
22Sun12:426.44:456.88:280.59:255.96:158:15Waxing Gibbous22Sun
23Mon1:356.45:177.19:110.210:035.86:178:13Waxing Gibbous23Mon
24Tue2:296.55:447.29:51-0.110:345.56:188:11Waxing Gibbous24Tue
25Wed3:216.66:077.310:28-0.311:045.16:198:09Full Moon25Wed
26Thu4:116.76:297.411:04-0.411:374.66:218:07Full Moon26Thu
27Fri5:016.86:537.511:41-0.36:228:05Full Moon27Fri
28Sat5:526.87:207.612:144.012:190.16:248:03Waning Gibbous28Sat
29Sun6:466.67:497.612:563.312:590.76:258:01Waning Gibbous29Sun
30Mon7:436.48:217.61:412.51:411.66:267:59Waning Gibbous30Mon
31Tue8:476.28:557.52:311.72:262.66:287:57Waning Gibbous31Tue
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 4:41 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 28% 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 Waning Crescent (28% 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