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

TIDE TIMES for Monday, August 3, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide (tomorrow) : 3:45 am (2.0 ft)
Next high tide : in 2h 33m at 9:11 pm (7.7 ft)
Sunset today : 8:47 pm
Sunrise tomorrow : 5:50 am
Moon phase : Waning Gibbous (74% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Aug 2092

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri2:516.76:247.310:21-0.711:006.15:498:49New Moon1Fri
2Sat3:376.76:507.410:56-0.911:345.85:508:47New Moon2Sat
3Sun4:246.77:147.511:32-1.05:518:45New Moon3Sun
4Mon5:106.77:387.612:095.512:08-0.95:538:44New Moon4Mon
5Tue5:596.68:057.712:485.112:46-0.65:548:42Waxing Crescent5Tue
6Wed6:506.38:347.71:324.61:24-0.15:558:41Waxing Crescent6Wed
7Thu7:476.09:067.72:193.92:050.75:578:39Waxing Crescent7Thu
8Fri8:505.69:397.73:103.12:481.75:588:37Waxing Crescent8Fri
9Sat10:065.310:157.64:052.23:352.85:598:36First Quarter9Sat
10Sun11:415.210:547.55:021.34:303.96:018:34First Quarter10Sun
11Mon1:375.56:010.55:395.06:028:32First Quarter11Mon
12Tue3:076.17:01-0.36:585.66:048:31Waxing Gibbous12Tue
13Wed12:277.44:086.87:59-0.98:155.96:058:29Waxing Gibbous13Wed
14Thu1:237.34:567.38:53-1.49:205.86:068:27Waxing Gibbous14Thu
15Fri2:237.35:377.69:44-1.710:155.56:088:25Full Moon15Fri
16Sat3:247.26:147.810:31-1.611:045.06:098:23Full Moon16Sat
17Sun4:237.16:487.811:15-1.311:524.56:108:22Full Moon17Sun
18Mon5:207.07:207.811:59-0.86:128:20Full Moon18Mon
19Tue6:146.77:517.712:394.012:41-0.16:138:18Waning Gibbous19Tue
20Wed7:096.48:207.51:273.41:240.96:158:16Waning Gibbous20Wed
21Thu8:056.08:487.32:162.92:081.96:168:14Waning Gibbous21Thu
22Fri9:085.79:177.13:062.42:542.96:178:12Waning Gibbous22Fri
23Sat10:255.59:486.93:572.03:454.06:198:10Third Quarter23Sat
24Sun12:145.44:501.74:474.96:208:08Third Quarter24Sun
25Mon2:005.85:451.46:055.56:228:06Third Quarter25Mon
26Tue3:136.26:421.27:335.96:238:04Third Quarter26Tue
27Wed4:036.67:380.98:475.96:248:02Waning Crescent27Wed
28Thu12:486.24:406.98:280.69:355.86:268:00Waning Crescent28Thu
29Fri1:456.25:107.19:120.310:075.56:277:58Waning Crescent29Fri
30Sat2:406.45:347.29:520.110:355.26:297:56Waning Crescent30Sat
31Sun3:336.55:567.310:30-0.111:044.76:307:54New Moon31Sun
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 12:28 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 74% 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 Waning Gibbous (74% 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