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

TIDE TIMES for Thursday, July 30, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 4h 00m at 12:01 pm (-1.0 ft)
Next high tide : 7:46 pm (7.7 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 - Feb 1978

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed10:058.03:354.85:240.97:415:10Third Quarter1Wed
2Thu1:185.810:49 AM7.94:475.76:220.07:405:12Waning Crescent2Thu
3Fri2:376.511:40 AM7.86:126.37:18-0.77:395:13Waning Crescent3Fri
4Sat3:297.212:387.87:296.48:10-1.37:375:15Waning Crescent4Sat
5Sun4:117.71:407.88:336.28:59-1.67:365:17Waning Crescent5Sun
6Mon4:498.12:437.79:295.89:46-1.67:345:18New Moon6Mon
7Tue5:258.43:437.610:215.210:31-1.37:335:20New Moon7Tue
8Wed5:598.54:427.411:124.611:15-0.77:315:22New Moon8Wed
9Thu6:328.55:407.012:044.07:295:23Waxing Crescent9Thu
10Fri7:058.56:386.612:563.37:285:25Waxing Crescent10Fri
11Sat7:378.37:416.212:431.21:502.87:265:27Waxing Crescent11Sat
12Sun8:098.18:545.81:292.42:442.37:255:28Waxing Crescent12Sun
13Mon8:427.810:325.62:163.63:391.97:235:30First Quarter13Mon
14Tue9:177.53:094.64:371.77:215:31First Quarter14Tue
15Wed12:265.89:56 AM7.24:165.65:361.47:205:33First Quarter15Wed
16Thu1:556.310:41 AM6.95:416.26:341.27:185:35First Quarter16Thu
17Fri2:556.811:33 AM6.77:126.47:260.97:165:36Waxing Gibbous17Fri
18Sat3:397.112:306.68:226.38:110.77:145:38Waxing Gibbous18Sat
19Sun4:137.41:276.69:076.18:500.57:125:40Waxing Gibbous19Sun
20Mon4:407.52:206.79:395.89:260.47:115:41Waxing Gibbous20Mon
21Tue5:027.63:096.810:075.410:000.47:095:43Full Moon21Tue
22Wed5:217.63:576.810:374.910:330.57:075:44Full Moon22Wed
23Thu5:407.74:446.811:094.311:070.87:055:46Full Moon23Thu
24Fri6:027.85:326.711:443.711:431.37:035:48Full Moon24Fri
25Sat6:297.96:236.612:233.07:015:49Waning Gibbous25Sat
26Sun6:587.97:186.412:202.01:062.26:595:51Waning Gibbous26Sun
27Mon7:297.88:216.112:592.81:531.66:575:52Waning Gibbous27Mon
28Tue8:037.79:376.01:423.72:441.06:555:54Third Quarter28Tue
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 3:53 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 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