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

TIDE TIMES for Thursday, July 23, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 4h 17m at 7:27 am (0.2 ft)
Next high tide : 4:07 pm (6.4 ft)
Sunset today : 9:02 pm
Sunrise tomorrow : 5:35 am
Moon phase : Waxing Gibbous (72% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Aug 2074

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed2:025.36:320.55:564.85:488:49First Quarter1Wed
2Thu12:017.73:306.17:28-0.47:145.65:498:48Waxing Gibbous2Thu
3Fri12:477.64:316.88:22-1.28:296.05:508:46Waxing Gibbous3Fri
4Sat1:387.55:187.49:13-1.89:336.15:528:45Waxing Gibbous4Sat
5Sun2:347.46:007.710:01-2.010:295.95:538:43Full Moon5Sun
6Mon3:317.36:387.910:46-2.011:205.55:548:42Full Moon6Mon
7Tue4:277.27:137.911:30-1.85:568:40Full Moon7Tue
8Wed5:227.07:477.912:105.112:13-1.25:578:38Full Moon8Wed
9Thu6:166.68:187.81:004.612:56-0.55:588:37Waning Gibbous9Thu
10Fri7:106.28:487.61:514.11:390.46:008:35Waning Gibbous10Fri
11Sat8:065.89:167.42:423.62:221.56:018:33Waning Gibbous11Sat
12Sun9:095.49:447.23:353.03:062.66:038:32Third Quarter12Sun
13Mon10:285.110:137.04:272.53:543.76:048:30Third Quarter13Mon
14Tue12:295.15:202.04:524.76:058:28Third Quarter14Tue
15Wed2:245.56:141.56:065.56:078:26Third Quarter15Wed
16Thu3:376.17:071.17:305.96:088:25Third Quarter16Thu
17Fri12:076.54:266.57:570.78:446.16:108:23Waning Crescent17Fri
18Sat12:566.45:026.98:430.39:366.16:118:21Waning Crescent18Sat
19Sun1:486.55:317.19:25-0.110:125.96:128:19Waning Crescent19Sun
20Mon2:416.65:577.310:04-0.510:425.76:148:17New Moon20Mon
21Tue3:326.76:207.410:41-0.711:145.36:158:15New Moon21Tue
22Wed4:236.86:447.511:19-0.811:494.86:178:13New Moon22Wed
23Thu5:146.87:097.611:57-0.66:188:11New Moon23Thu
24Fri6:076.77:377.612:294.112:37-0.16:198:09Waxing Crescent24Fri
25Sat7:036.68:077.71:143.31:180.66:218:07Waxing Crescent25Sat
26Sun8:046.38:407.62:022.52:011.66:228:05Waxing Crescent26Sun
27Mon9:136.09:147.52:541.72:482.86:248:04Waxing Crescent27Mon
28Tue10:365.79:537.43:500.93:413.96:258:02First Quarter28Tue
29Wed12:205.84:490.34:464.96:268:00First Quarter29Wed
30Thu2:016.25:52-0.16:075.76:287:57First Quarter30Thu
31Fri3:136.86:57-0.57:345.96:297:55Waxing Gibbous31Fri
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 11:47 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 72% 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 Waxing Gibbous (72% 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