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

TIDE TIMES for Thursday, July 23, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 7:27 am (0.2 ft)
Next high tide (tomorrow) : in 1h 15m 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 - Aug 1987

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat10:074.810:057.54:222.53:183.45:468:51First Quarter1Sat
2Sun11:524.810:317.55:081.53:554.65:478:49First Quarter2Sun
3Mon2:355.45:580.44:455.85:498:48First Quarter3Mon
4Tue4:066.36:51-0.56:176.85:508:46Waxing Gibbous4Tue
5Wed4:507.07:46-1.47:527.25:518:45Waxing Gibbous5Wed
6Thu12:197.55:267.58:41-2.19:037.35:538:43Waxing Gibbous6Thu
7Fri1:227.66:007.89:34-2.610:007.05:548:42Waxing Gibbous7Fri
8Sat2:337.66:317.910:25-2.910:526.45:568:40Full Moon8Sat
9Sun3:437.67:028.011:13-2.711:445.75:578:38Full Moon9Sun
10Mon4:517.47:328.011:59-2.15:588:37Full Moon10Mon
11Tue5:577.08:008.012:384.812:43-1.26:008:35Waning Gibbous11Tue
12Wed7:046.58:288.01:343.81:270.16:018:33Waning Gibbous12Wed
13Thu8:156.08:567.92:312.72:111.66:028:32Waning Gibbous13Thu
14Fri9:375.59:237.73:271.82:563.16:048:30Third Quarter14Fri
15Sat11:245.49:517.44:221.03:474.66:058:28Third Quarter15Sat
16Sun1:265.85:180.44:545.86:078:26Third Quarter16Sun
17Mon3:016.56:150.16:356.66:088:24Third Quarter17Mon
18Tue4:027.17:13-0.18:536.86:098:23Waning Crescent18Tue
19Wed4:477.48:09-0.210:136.66:118:21Waning Crescent19Wed
20Thu12:436.35:247.59:01-0.310:466.46:128:19Waning Crescent20Thu
21Fri1:496.25:557.59:46-0.411:036.16:148:17Waning Crescent21Fri
22Sat2:506.36:207.510:25-0.411:205.86:158:15New Moon22Sat
23Sun3:446.46:407.411:00-0.311:435.46:168:13New Moon23Sun
24Mon4:336.56:567.411:32-0.16:188:11New Moon24Mon
25Tue5:216.47:117.412:124.812:040.36:198:09New Moon25Tue
26Wed6:106.37:277.412:444.112:360.96:218:07Waxing Crescent26Wed
27Thu7:026.17:487.41:183.31:081.76:228:05Waxing Crescent27Thu
28Fri7:585.98:107.41:562.41:412.76:238:03Waxing Crescent28Fri
29Sat9:035.78:347.32:361.62:173.86:258:01Waxing Crescent29Sat
30Sun10:215.78:587.23:210.82:554.96:267:59First Quarter30Sun
31Mon12:135.84:100.13:435.96:287:57First Quarter31Mon
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