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

TIDE TIMES for Friday, July 17, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 4h 18m at 1:44 am (5.4 ft)
Next high tide : 6:35 am (6.6 ft)
Sunset today : 9:09 pm
Sunrise tomorrow : 5:27 am
Moon phase : Waxing Crescent (8% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Jul 2069

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Mon1:507.15:567.09:39-0.59:576.45:159:18Waxing Gibbous1Mon
2Tue2:317.06:277.310:12-1.010:406.45:159:18Full Moon2Tue
3Wed3:147.06:557.510:46-1.311:206.45:169:17Full Moon3Wed
4Thu3:597.07:227.711:21-1.65:179:17Full Moon4Thu
5Fri4:466.97:497.812:016.211:58 AM-1.65:189:16Full Moon5Fri
6Sat5:356.78:187.912:465.812:37-1.55:189:16Waning Gibbous6Sat
7Sun6:286.48:488.01:345.41:17-1.05:199:15Waning Gibbous7Sun
8Mon7:266.09:208.12:274.71:58-0.35:209:15Waning Gibbous8Mon
9Tue8:305.59:538.13:233.82:420.75:219:14Waning Gibbous9Tue
10Wed9:455.010:288.04:202.93:271.95:229:14Third Quarter10Wed
11Thu11:174.811:058.05:181.84:183.15:239:13Third Quarter11Thu
12Fri1:165.06:160.85:184.45:249:12Third Quarter12Fri
13Sat3:015.67:12-0.26:315.35:259:11Waning Crescent13Sat
14Sun12:297.84:116.48:06-1.07:505.95:269:10Waning Crescent14Sun
15Mon1:177.75:027.08:57-1.79:016.25:279:10Waning Crescent15Mon
16Tue2:107.65:467.59:44-2.010:026.15:289:09New Moon16Tue
17Wed3:067.46:257.810:29-2.110:575.85:299:08New Moon17Wed
18Thu4:027.27:017.911:12-1.911:495.55:309:07New Moon18Thu
19Fri4:567.07:348.011:54-1.55:329:06New Moon19Fri
20Sat5:496.68:067.912:415.012:35-0.95:339:05Waxing Crescent20Sat
21Sun6:426.28:357.81:334.51:17-0.15:349:04Waxing Crescent21Sun
22Mon7:375.89:037.72:264.01:580.95:359:02Waxing Crescent22Mon
23Tue8:365.39:307.63:193.42:401.95:369:01Waxing Crescent23Tue
24Wed9:455.09:587.44:112.83:233.05:389:00First Quarter24Wed
25Thu11:224.810:297.25:032.34:114.05:398:59First Quarter25Thu
26Fri1:385.05:561.85:085.05:408:57First Quarter26Fri
27Sat3:135.56:481.36:225.75:418:56First Quarter27Sat
28Sun4:126.17:380.87:406.15:438:55Waxing Gibbous28Sun
29Mon12:286.84:526.58:240.38:456.35:448:53Waxing Gibbous29Mon
30Tue1:166.85:246.99:05-0.29:356.25:458:52Waxing Gibbous30Tue
31Wed2:076.95:507.19:44-0.610:146.05:478:51Waxing Gibbous31Wed
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 4:09 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 8% 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 Waxing Crescent (8% 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