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

TIDE TIMES for Wednesday, July 22, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 5:41 pm (5.8 ft)
Next high tide : in 6h 52m at 2:48 pm (5.6 ft)
Sunset today : 9:03 pm
Sunrise tomorrow : 5:34 am
Moon phase : First Quarter (63% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Aug 1988

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Mon7:146.48:498.21:554.11:42-0.25:478:50Waning Gibbous1Mon
2Tue8:295.89:188.12:542.92:261.35:488:48Waning Gibbous2Tue
3Wed9:565.39:488.03:541.73:112.95:508:47Third Quarter3Wed
4Thu11:525.210:207.84:530.74:024.55:518:45Third Quarter4Thu
5Fri1:585.85:52-0.15:075.85:528:44Third Quarter5Fri
6Sat3:296.66:51-0.66:436.75:548:42Waning Crescent6Sat
7Sun4:277.27:48-0.98:377.05:558:40Waning Crescent7Sun
8Mon12:236.95:107.68:42-1.110:066.95:578:39Waning Crescent8Mon
9Tue1:226.75:477.89:31-1.110:506.65:588:37Waning Crescent9Tue
10Wed2:256.66:207.810:14-1.011:176.35:598:35New Moon10Wed
11Thu3:236.56:487.710:53-0.911:445.96:018:34New Moon11Thu
12Fri4:166.57:117.511:28-0.66:028:32New Moon12Fri
13Sat5:046.47:297.412:145.412:02-0.26:038:30New Moon13Sat
14Sun5:526.37:447.412:484.812:350.46:058:28Waxing Crescent14Sun
15Mon6:416.08:007.41:244.11:081.16:068:27Waxing Crescent15Mon
16Tue7:345.88:197.32:023.41:402.16:088:25Waxing Crescent16Tue
17Wed8:325.58:417.32:412.62:123.16:098:23Waxing Crescent17Wed
18Thu9:405.39:057.13:211.92:454.26:108:21First Quarter18Thu
19Fri11:125.39:297.04:051.33:185.26:128:19First Quarter19Fri
20Sat1:585.64:530.73:596.16:138:17First Quarter20Sat
21Sun3:416.35:480.15:366.96:158:15First Quarter21Sun
22Mon4:186.86:49-0.47:297.26:168:14Waxing Gibbous22Mon
23Tue4:487.27:50-1.08:397.16:178:12Waxing Gibbous23Tue
24Wed12:327.05:147.48:46-1.59:276.76:198:10Waxing Gibbous24Wed
25Thu1:507.15:407.69:38-1.810:116.06:208:08Waxing Gibbous25Thu
26Fri3:037.26:047.710:25-1.810:555.16:228:06Full Moon26Fri
27Sat4:137.36:287.811:10-1.411:423.96:238:04Full Moon27Sat
28Sun5:207.26:537.911:53-0.66:248:02Full Moon28Sun
29Mon6:276.97:197.912:312.712:350.66:268:00Waning Gibbous29Mon
30Tue7:366.67:467.91:211.51:192.06:277:58Waning Gibbous30Tue
31Wed8:516.48:157.82:130.52:053.56:297:56Waning 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 4:14 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 63% 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 First Quarter (63% 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