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

TIDE TIMES for Saturday, July 4, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 4h 14m at 3:18 am (5.7 ft)
Next high tide : 7:07 am (5.7 ft)
Sunset today : 9:17 pm
Sunrise tomorrow : 5:16 am
Moon phase : Waning Gibbous (87% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Aug 2051

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue3:116.17:10-0.46:555.75:478:50Waning Crescent1Tue
2Wed12:307.44:116.78:08-0.88:165.95:488:49Waning Crescent2Wed
3Thu1:267.24:597.29:00-1.19:235.95:508:47Waning Crescent3Thu
4Fri2:257.15:397.59:47-1.210:185.65:518:46New Moon4Fri
5Sat3:237.06:147.610:30-1.111:055.25:528:44New Moon5Sat
6Sun4:186.86:467.711:10-0.911:494.85:548:42New Moon6Sun
7Mon5:096.77:147.611:49-0.45:558:41New Moon7Mon
8Tue5:586.57:397.612:314.312:280.25:568:39Waxing Crescent8Tue
9Wed6:476.28:037.51:143.81:060.95:588:38Waxing Crescent9Wed
10Thu7:375.98:277.41:583.31:451.75:598:36Waxing Crescent10Thu
11Fri8:315.68:547.32:442.92:262.66:018:34Waxing Crescent11Fri
12Sat9:335.39:247.13:312.43:083.56:028:32First Quarter12Sat
13Sun10:525.29:587.04:202.03:554.46:038:31First Quarter13Sun
14Mon12:565.25:111.74:535.26:058:29First Quarter14Mon
15Tue2:395.66:061.36:085.76:068:27First Quarter15Tue
16Wed3:396.17:010.97:266.06:078:25Waxing Gibbous16Wed
17Thu12:106.64:186.57:530.58:296.06:098:23Waxing Gibbous17Thu
18Fri1:056.64:486.88:410.09:165.86:108:22Waxing Gibbous18Fri
19Sat2:026.75:147.09:25-0.49:565.46:128:20Waxing Gibbous19Sat
20Sun2:596.95:397.210:06-0.710:344.86:138:18Full Moon20Sun
21Mon3:577.06:047.410:46-0.711:154.16:148:16Full Moon21Mon
22Tue4:547.16:317.611:27-0.511:593.26:168:14Full Moon22Tue
23Wed5:517.07:017.712:090.16:178:12Waning Gibbous23Wed
24Thu6:516.87:347.812:462.312:520.96:198:10Waning Gibbous24Thu
25Fri7:536.68:087.81:361.51:371.96:208:08Waning Gibbous25Fri
26Sat9:016.38:467.72:290.82:263.06:218:06Waning Gibbous26Sat
27Sun10:216.09:287.53:260.33:214.16:238:04Third Quarter27Sun
28Mon11:576.010:157.24:260.04:265.06:248:02Third Quarter28Mon
29Tue1:326.35:31-0.15:485.56:268:00Third Quarter29Tue
30Wed2:456.76:38-0.17:205.76:277:58Waning Crescent30Wed
31Thu12:156.63:407.07:42-0.18:415.46:287:56Waning Crescent31Thu
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 5:12 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 87% 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 Waning Gibbous (87% 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