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 (tomorrow) : 7:27 am (0.2 ft)
Next high tide : in 4h 14m at 11:18 pm (7.2 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 - Nov 1987

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun12:015.31:498.06:241.48:163.26:584:53Waxing Gibbous1Sun
2Mon1:485.62:158.07:232.48:471.77:004:52Waxing Gibbous2Mon
3Tue3:126.12:387.98:153.49:190.47:014:50Waxing Gibbous3Tue
4Wed4:206.82:597.99:044.49:51-0.77:034:48Full Moon4Wed
5Thu5:187.43:217.89:525.410:24-1.57:054:47Full Moon5Thu
6Fri6:117.93:437.610:426.210:59-1.97:064:45Full Moon6Fri
7Sat7:028.24:067.311:356.811:35-1.97:084:44Waning Gibbous7Sat
8Sun7:538.34:287.012:387.17:094:43Waning Gibbous8Sun
9Mon8:458.34:416.712:15-1.62:027.27:114:41Waning Gibbous9Mon
10Tue9:398.212:57-1.17:124:40Waning Gibbous10Tue
11Wed10:348.01:44-0.47:144:38Third Quarter11Wed
12Thu11:247.92:350.37:164:37Third Quarter12Thu
13Fri12:047.83:301.07:485.37:174:36Third Quarter13Fri
14Sat12:347.74:281.87:574.67:194:34Third Quarter14Sat
15Sun12:547.75:272.58:053.77:204:33Waning Crescent15Sun
16Mon12:504.81:107.66:223.38:162.77:224:32Waning Crescent16Mon
17Tue2:265.31:277.77:144.18:341.57:234:31Waning Crescent17Tue
18Wed3:336.01:487.78:014.98:570.37:254:30Waning Crescent18Wed
19Thu4:276.72:107.88:475.69:25-0.97:264:29New Moon19Thu
20Fri5:157.42:347.89:316.39:58-1.97:284:28New Moon20Fri
21Sat6:018.02:587.910:166.910:35-2.67:294:27New Moon21Sat
22Sun6:488.43:237.811:047.411:17-2.97:314:26New Moon22Sun
23Mon7:378.53:507.711:577.77:324:25Waxing Crescent23Mon
24Tue8:298.64:227.512:03-2.91:017.77:344:24Waxing Crescent24Tue
25Wed9:228.65:047.012:53-2.52:247.57:354:23Waxing Crescent25Wed
26Thu10:128.56:416.31:46-1.74:216.87:364:22First Quarter26Thu
27Fri10:588.58:355.42:42-0.76:035.77:384:22First Quarter27Fri
28Sat11:378.410:324.93:390.56:454.47:394:21First Quarter28Sat
29Sun12:118.44:391.97:212.97:404:20Waxing Gibbous29Sun
30Mon12:484.912:408.35:423.37:541.57:424:20Waxing Gibbous30Mon
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 3:22 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 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