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

TIDE TIMES for Saturday, August 1, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide (tomorrow) : 2:14 am (4.1 ft)
Next high tide : in 1h 35m at 8:25 pm (7.8 ft)
Sunset today : 8:50 pm
Sunrise tomorrow : 5:47 am
Moon phase : Waning Gibbous (90% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Apr 1973

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun3:247.23:216.49:212.89:162.25:496:43New Moon1Sun
2Mon3:437.44:206.79:521.69:552.85:476:44New Moon2Mon
3Tue4:077.55:177.110:280.410:353.65:456:46New Moon3Tue
4Wed4:347.66:137.311:07-0.711:174.45:436:47New Moon4Wed
5Thu5:047.77:127.411:49-1.45:416:49Waxing Crescent5Thu
6Fri5:377.68:157.412:045.212:36-1.85:396:50Waxing Crescent6Fri
7Sat6:137.59:257.312:555.81:27-1.95:376:52Waxing Crescent7Sat
8Sun6:547.210:407.31:576.32:23-1.55:356:53First Quarter8Sun
9Mon7:466.711:517.33:166.53:24-1.05:336:54First Quarter9Mon
10Tue8:576.25:016.24:30-0.35:316:56First Quarter10Tue
11Wed12:497.410:28 AM5.76:525.55:390.55:296:57First Quarter11Wed
12Thu1:357.512:145.47:524.66:441.25:276:59Waxing Gibbous12Thu
13Fri2:127.51:535.68:313.57:421.95:257:00Waxing Gibbous13Fri
14Sat2:437.53:116.09:022.48:322.75:237:02Waxing Gibbous14Sat
15Sun3:097.44:136.49:311.49:183.45:217:03Full Moon15Sun
16Mon3:307.45:076.810:000.610:014.25:197:05Full Moon16Mon
17Tue3:507.35:557.110:30-0.110:444.85:177:06Full Moon17Tue
18Wed4:117.16:417.311:02-0.611:285.45:157:08Full Moon18Wed
19Thu4:367.07:277.411:35-0.85:137:09Waning Gibbous19Thu
20Fri5:056.88:137.412:165.812:12-0.85:117:11Waning Gibbous20Fri
21Sat5:366.69:037.31:106.112:51-0.75:097:12Waning Gibbous21Sat
22Sun6:116.49:587.22:116.31:34-0.35:087:14Waning Gibbous22Sun
23Mon6:496.110:547.13:256.32:210.15:067:15Third Quarter23Mon
24Tue7:365.711:447.14:586.13:120.55:047:17Third Quarter24Tue
25Wed8:445.36:295.74:081.05:027:18Third Quarter25Wed
26Thu12:227.110:07 AM5.07:065.15:061.65:007:19Third Quarter26Thu
27Fri12:517.111:36 AM4.97:264.36:042.14:587:21Waning Crescent27Fri
28Sat1:157.11:085.17:493.36:592.74:577:22Waning Crescent28Sat
29Sun1:387.23:315.69:152.18:493.45:558:24Waning Crescent29Sun
30Mon3:037.34:406.39:460.79:374.15:538:25Waning Crescent30Mon
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 11:19 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 90% 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 (90% 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