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

TIDE TIMES for Sunday, July 19, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 3:52 am (3.5 ft)
Next high tide (tomorrow) : in 11m at 9:31 pm (8.1 ft)
Sunset today : 9:07 pm
Sunrise tomorrow : 5:30 am
Moon phase : Waxing Crescent (24% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - May 2071

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri5:367.47:507.612:22-1.75:518:27Waxing Crescent1Fri
2Sat6:147.38:447.712:475.11:07-2.05:508:29Waxing Crescent2Sat
3Sun6:567.19:407.71:425.51:55-1.95:488:30Waxing Crescent3Sun
4Mon7:436.710:407.72:465.72:47-1.65:468:31Waxing Crescent4Mon
5Tue8:396.211:397.74:025.63:43-0.95:458:33First Quarter5Tue
6Wed9:495.65:295.24:43-0.15:438:34First Quarter6Wed
7Thu12:357.711:16 AM5.26:584.55:460.85:428:36First Quarter7Thu
8Fri1:257.71:005.08:053.56:521.75:408:37Waxing Gibbous8Fri
9Sat2:097.72:435.38:522.57:562.65:398:39Waxing Gibbous9Sat
10Sun2:477.64:015.89:291.58:543.35:378:40Waxing Gibbous10Sun
11Mon3:207.55:036.410:030.69:474.05:368:41Waxing Gibbous11Mon
12Tue3:507.45:566.910:35-0.110:364.65:348:43Full Moon12Tue
13Wed4:177.36:437.211:08-0.611:235.15:338:44Full Moon13Wed
14Thu4:467.17:277.511:41-1.05:328:45Full Moon14Thu
15Fri5:166.98:097.612:115.412:15-1.15:308:47Full Moon15Fri
16Sat5:496.78:517.71:025.712:52-1.05:298:48Waning Gibbous16Sat
17Sun6:266.49:327.61:585.81:31-0.85:288:49Waning Gibbous17Sun
18Mon7:056.110:147.63:005.82:12-0.45:278:51Waning Gibbous18Mon
19Tue7:505.710:557.54:095.72:540.15:268:52Waning Gibbous19Tue
20Wed8:425.311:357.45:245.43:400.75:248:53Third Quarter20Wed
21Thu9:454.96:334.94:281.45:238:54Third Quarter21Thu
22Fri12:117.411:02 AM4.67:224.35:212.15:228:56Third Quarter22Fri
23Sat12:457.312:304.57:563.56:192.85:218:57Third Quarter23Sat
24Sun1:187.32:074.88:252.67:183.45:208:58Waning Crescent24Sun
25Mon1:507.43:325.38:541.68:144.05:198:59Waning Crescent25Mon
26Tue2:237.44:356.09:250.49:074.55:189:00Waning Crescent26Tue
27Wed2:577.55:276.79:59-0.79:575.05:189:01Waning Crescent27Wed
28Thu3:337.66:157.210:37-1.610:465.45:179:02New Moon28Thu
29Fri4:117.67:027.711:18-2.411:375.75:169:03New Moon29Fri
30Sat4:537.57:498.012:01-2.85:159:04New Moon30Sat
31Sun5:407.48:378.212:325.812:47-2.85:149:05Waxing Crescent31Sun
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 12:41 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 24% 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 Crescent (24% 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