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

TIDE TIMES for Tuesday, August 4, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide (tomorrow) : 4:34 am (1.0 ft)
Next high tide : in 4h 53m at 9:37 pm (7.7 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 - Aug 2094

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun8:505.710:018.03:273.42:590.95:488:49Third Quarter1Sun
2Mon10:175.210:377.94:312.43:502.45:498:48Third Quarter2Mon
3Tue12:125.15:351.54:473.95:518:46Third Quarter3Tue
4Wed2:095.66:360.75:585.15:528:45Third Quarter4Wed
5Thu3:336.37:330.07:245.95:538:43Waning Crescent5Thu
6Fri12:357.14:337.08:24-0.58:506.35:558:42Waning Crescent6Fri
7Sat1:216.85:197.49:10-0.710:006.35:568:40Waning Crescent7Sat
8Sun2:106.75:587.69:51-0.910:486.25:578:38Waning Crescent8Sun
9Mon3:006.66:317.710:29-0.911:236.05:598:37New Moon9Mon
10Tue3:496.67:017.611:06-0.811:555.76:008:35New Moon10Tue
11Wed4:356.57:267.511:42-0.66:018:33New Moon11Wed
12Thu5:206.57:487.512:285.412:18-0.36:038:31New Moon12Thu
13Fri6:066.38:087.41:055.012:530.26:048:30Waxing Crescent13Fri
14Sat6:536.18:297.41:434.51:280.86:068:28Waxing Crescent14Sat
15Sun7:435.88:537.42:243.92:041.56:078:26Waxing Crescent15Sun
16Mon8:405.59:217.33:073.32:402.46:088:24Waxing Crescent16Mon
17Tue9:465.29:507.13:522.63:183.46:108:22First Quarter17Tue
18Wed11:105.110:227.04:391.94:014.46:118:21First Quarter18Wed
19Thu1:155.35:291.25:005.46:138:19First Quarter19Thu
20Fri3:025.96:240.56:236.16:148:17First Quarter20Fri
21Sat4:006.57:20-0.37:446.46:158:15Waxing Gibbous21Sat
22Sun12:277.04:417.08:15-1.08:486.46:178:13Waxing Gibbous22Sun
23Mon1:277.15:177.49:07-1.69:406.16:188:11Waxing Gibbous23Mon
24Tue2:317.25:497.69:57-1.910:275.66:208:09Full Moon24Tue
25Wed3:367.46:217.810:45-2.011:144.86:218:07Full Moon25Wed
26Thu4:407.46:527.911:31-1.66:228:05Full Moon26Thu
27Fri5:427.37:237.912:034.012:17-0.96:248:03Waning Gibbous27Fri
28Sat6:467.07:557.912:553.11:030.16:258:01Waning Gibbous28Sat
29Sun7:526.68:287.81:482.21:501.46:277:59Waning Gibbous29Sun
30Mon9:056.29:017.62:441.52:402.86:287:57Waning Gibbous30Mon
31Tue10:336.09:377.33:410.93:354.16:297:55Third Quarter31Tue
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (9449834)

Common Questions About Roche Harbor, San Juan Island, WA Tides

Show All
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 1:05 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