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 2h 18m 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 - Jan 2084

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat10:078.33:074.05:311.58:044:27Third Quarter1Sat
2Sun12:595.210:38 AM8.33:595.46:190.28:044:28Third Quarter2Sun
3Mon2:536.211:11 AM8.35:176.67:08-1.08:044:29Waning Crescent3Mon
4Tue3:507.111:50 AM8.46:467.47:57-2.08:044:30Waning Crescent4Tue
5Wed4:327.912:398.48:027.78:45-2.78:044:31Waning Crescent5Wed
6Thu5:118.41:378.39:057.79:32-3.08:034:33New Moon6Thu
7Fri5:478.72:408.210:027.410:19-3.08:034:34New Moon7Fri
8Sat6:238.93:447.910:596.911:05-2.58:034:35New Moon8Sat
9Sun6:579.04:477.511:586.311:50-1.78:024:36Waxing Crescent9Sun
10Mon7:318.95:506.81:005.58:024:37Waxing Crescent10Mon
11Tue8:038.96:576.112:35-0.62:034.58:014:39Waxing Crescent11Tue
12Wed8:348.78:135.51:180.83:053.68:014:40Waxing Crescent12Wed
13Thu9:038.69:555.12:012.34:042.68:004:41First Quarter13Thu
14Fri9:318.32:443.85:011.87:594:43First Quarter14Fri
15Sat12:175.39:59 AM8.03:345.35:541.17:594:44First Quarter15Sat
16Sun2:146.110:29 AM7.74:456.56:440.57:584:46Waxing Gibbous16Sun
17Mon3:246.911:04 AM7.56:257.27:290.17:574:47Waxing Gibbous17Mon
18Tue4:097.511:45 AM7.38:067.58:11-0.27:564:49Waxing Gibbous18Tue
19Wed4:457.912:347.29:187.58:50-0.57:554:50Waxing Gibbous19Wed
20Thu5:168.11:277.19:597.39:26-0.67:554:52Waxing Gibbous20Thu
21Fri5:438.22:207.110:277.110:00-0.77:544:53Full Moon21Fri
22Sat6:068.23:107.110:556.810:34-0.77:534:55Full Moon22Sat
23Sun6:268.23:597.011:276.411:07-0.57:524:56Full Moon23Sun
24Mon6:448.24:486.812:025.97:514:58Full Moon24Mon
25Tue7:038.35:406.412:415.27:494:59Waning Gibbous25Tue
26Wed7:248.46:366.112:130.61:234.37:485:01Waning Gibbous26Wed
27Thu7:488.47:405.712:471.52:073.37:475:02Waning Gibbous27Thu
28Fri8:148.38:575.41:212.62:542.37:465:04Third Quarter28Fri
29Sat8:418.210:435.31:573.93:451.37:455:06Third Quarter29Sat
30Sun9:108.22:355.14:400.47:435:07Third Quarter30Sun
31Mon1:205.89:43 AM8.13:266.35:40-0.47:425:09Third Quarter31Mon
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