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

TIDE TIMES for Tuesday, August 4, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 9m at 3:45 am (2.0 ft)
Next high tide : 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 - May 2093

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri7:575.911:537.34:396.13:250.15:508:28First Quarter1Fri
2Sat8:415.56:525.94:160.55:498:30First Quarter2Sat
3Sun12:477.29:46 AM5.18:165.55:121.05:478:31First Quarter3Sun
4Mon1:337.211:09 AM4.88:495.06:121.55:458:32First Quarter4Mon
5Tue2:077.212:364.89:024.57:121.95:448:34Waxing Gibbous5Tue
6Wed2:347.22:025.09:133.78:062.35:428:35Waxing Gibbous6Wed
7Thu2:597.33:215.49:322.88:552.75:418:37Waxing Gibbous7Thu
8Fri3:247.44:265.99:571.69:413.25:398:38Waxing Gibbous8Fri
9Sat3:517.55:246.510:270.410:263.85:388:40Full Moon9Sat
10Sun4:207.56:187.111:02-0.711:114.55:368:41Full Moon10Sun
11Mon4:517.67:117.511:40-1.711:595.15:358:42Full Moon11Mon
12Tue5:257.58:057.812:22-2.35:348:44Waning Gibbous12Tue
13Wed6:017.49:028.012:515.71:08-2.65:328:45Waning Gibbous13Wed
14Thu6:427.110:018.01:516.11:57-2.55:318:46Waning Gibbous14Thu
15Fri7:296.711:018.03:026.32:50-2.05:308:48Waning Gibbous15Fri
16Sat8:276.111:598.04:286.13:46-1.35:288:49Third Quarter16Sat
17Sun9:415.56:135.54:46-0.35:278:50Third Quarter17Sun
18Mon12:538.011:13 AM4.97:404.65:500.75:268:51Third Quarter18Mon
19Tue1:397.91:054.78:323.56:551.75:258:53Waning Crescent19Tue
20Wed2:197.82:525.09:102.57:572.75:248:54Waning Crescent20Wed
21Thu2:537.74:125.69:421.48:543.65:238:55Waning Crescent21Thu
22Fri3:217.65:146.210:110.59:474.45:228:56Waning Crescent22Fri
23Sat3:467.46:066.810:39-0.210:355.05:218:58New Moon23Sat
24Sun4:097.26:537.211:09-0.811:235.65:208:59New Moon24Sun
25Mon4:337.17:377.511:40-1.25:199:00New Moon25Mon
26Tue5:006.98:187.712:126.012:13-1.45:189:01New Moon26Tue
27Wed5:306.68:587.81:046.312:49-1.35:179:02Waxing Crescent27Wed
28Thu6:036.49:397.82:046.41:27-1.15:169:03Waxing Crescent28Thu
29Fri6:386.110:207.73:136.42:07-0.85:159:04Waxing Crescent29Fri
30Sat7:185.711:007.74:406.22:50-0.35:159:05Waxing Crescent30Sat
31Sun8:085.311:387.66:325.83:350.25:149:06First Quarter31Sun
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 6:44 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 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