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

TIDE TIMES for Tuesday, August 4, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 2:54 pm (3.2 ft)
Next high tide : in 4h 22m at 9:43 am (5.1 ft)
Sunset today : 8:45 pm
Sunrise tomorrow : 5:51 am
Moon phase : Third Quarter (64% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Jul 2093

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed10:264.511:417.76:064.04:282.05:159:18First Quarter1Wed
2Thu12:004.46:472.95:193.05:169:18First Quarter2Thu
3Fri12:147.71:584.77:261.86:204.15:169:17First Quarter3Fri
4Sat12:477.73:395.48:070.57:275.05:179:17Waxing Gibbous4Sat
5Sun1:227.74:446.38:48-0.88:325.75:189:16Waxing Gibbous5Sun
6Mon2:007.85:347.09:30-1.99:326.15:199:16Waxing Gibbous6Mon
7Tue2:427.96:207.610:14-2.710:286.35:209:15Full Moon7Tue
8Wed3:307.97:038.011:00-3.211:246.35:209:15Full Moon8Wed
9Thu4:227.87:458.211:47-3.35:219:14Full Moon9Thu
10Fri5:197.58:278.312:226.212:35-3.05:229:13Waning Gibbous10Fri
11Sat6:187.19:088.31:245.81:23-2.35:239:13Waning Gibbous11Sat
12Sun7:206.59:498.32:325.22:12-1.35:249:12Waning Gibbous12Sun
13Mon8:285.710:288.23:434.53:020.05:259:11Third Quarter13Mon
14Tue9:475.111:068.04:543.63:531.35:269:10Third Quarter14Tue
15Wed11:324.711:437.86:022.64:472.85:279:09Third Quarter15Wed
16Thu1:394.97:021.75:494.15:289:09Third Quarter16Thu
17Fri12:187.53:175.57:530.97:015.15:309:08Waning Crescent17Fri
18Sat12:537.34:266.38:360.28:175.95:319:07Waning Crescent18Sat
19Sun1:287.15:176.99:14-0.39:266.25:329:06Waning Crescent19Sun
20Mon2:046.95:587.39:49-0.710:236.45:339:04Waning Crescent20Mon
21Tue2:436.86:337.510:22-0.911:076.45:349:03New Moon21Tue
22Wed3:246.77:057.610:56-1.011:456.35:359:02New Moon22Wed
23Thu4:076.77:337.711:31-1.05:379:01New Moon23Thu
24Fri4:516.67:587.712:226.112:06-1.05:389:00New Moon24Fri
25Sat5:366.48:227.71:015.912:42-0.75:398:59Waxing Crescent25Sat
26Sun6:226.28:467.71:425.51:18-0.45:408:57Waxing Crescent26Sun
27Mon7:105.99:137.72:265.11:550.25:428:56Waxing Crescent27Mon
28Tue8:055.59:427.73:124.52:320.95:438:55Waxing Crescent28Tue
29Wed9:085.110:137.64:003.83:111.85:448:53First Quarter29Wed
30Thu10:244.810:457.54:492.93:542.95:468:52First Quarter30Thu
31Fri12:004.85:401.94:464.05:478:50First Quarter31Fri
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 12:18 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 64% 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 Third Quarter (64% 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