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

TIDE TIMES for Thursday, July 9, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 1h 33m at 7:08 am (-0.1 ft)
Next high tide : 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 - Mar 2000

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed3:387.312:106.48:416.37:590.66:525:56Waning Crescent1Wed
2Thu4:117.51:126.49:186.18:410.46:505:58Waning Crescent2Thu
3Fri4:387.62:096.69:435.89:190.26:486:00Waning Crescent3Fri
4Sat5:007.63:016.710:085.49:540.26:466:01New Moon4Sat
5Sun5:197.73:516.810:354.810:290.36:446:03New Moon5Sun
6Mon5:397.74:406.811:064.211:050.76:426:04New Moon6Mon
7Tue6:017.85:316.811:423.411:411.26:406:06New Moon7Tue
8Wed6:267.86:256.712:222.66:386:07Waxing Crescent8Wed
9Thu6:547.87:256.512:202.01:051.86:366:09Waxing Crescent9Thu
10Fri7:247.78:326.31:003.01:521.06:346:10Waxing Crescent10Fri
11Sat7:567.59:546.21:454.02:440.46:326:12First Quarter11Sat
12Sun8:327.411:386.32:385.13:420.06:306:13First Quarter12Sun
13Mon9:147.13:465.94:44-0.36:286:15First Quarter13Mon
14Tue1:136.710:09 AM6.95:176.45:51-0.56:266:16First Quarter14Tue
15Wed2:187.211:20 AM6.76:526.46:56-0.56:246:18Waxing Gibbous15Wed
16Thu3:067.612:406.68:055.97:55-0.56:226:20Waxing Gibbous16Thu
17Fri3:457.81:576.68:565.28:47-0.46:206:21Waxing Gibbous17Fri
18Sat4:197.93:066.79:384.49:340.06:176:23Full Moon18Sat
19Sun4:497.94:086.810:183.610:170.66:156:24Full Moon19Sun
20Mon5:167.95:046.810:582.811:001.36:136:26Full Moon20Mon
21Tue5:427.85:596.811:372.111:422.26:116:27Full Moon21Tue
22Wed6:067.66:536.712:171.56:096:29Waning Gibbous22Wed
23Thu6:317.47:516.612:253.212:591.16:076:30Waning Gibbous23Thu
24Fri6:587.28:566.51:124.11:410.86:056:31Waning Gibbous24Fri
25Sat7:276.910:166.52:054.92:260.76:036:33Waning Gibbous25Sat
26Sun7:596.511:476.63:085.63:150.86:016:34Third Quarter26Sun
27Mon8:376.24:316.14:101.05:596:36Third Quarter27Mon
28Tue1:046.89:27 AM5.96:216.15:111.15:576:37Third Quarter28Tue
29Wed2:007.010:32 AM5.77:535.96:131.25:546:39Third Quarter29Wed
30Thu2:417.111:46 AM5.68:335.67:111.25:526:40Waning Crescent30Thu
31Fri3:127.212:595.78:535.18:001.15:506:42Waning Crescent31Fri
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 11:16 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 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