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

TIDE TIMES for Monday, August 3, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 2:18 pm (1.9 ft)
Next high tide : in 1h 57m at 8:27 am (5.4 ft)
Sunset today : 8:47 pm
Sunrise tomorrow : 5:50 am
Moon phase : Waning Gibbous (74% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Jul 2091

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun4:157.57:288.111:30-2.55:159:18Full Moon1Sun
2Mon5:037.28:098.212:085.912:13-2.25:159:18Full Moon2Mon
3Tue5:526.88:488.21:065.812:56-1.75:169:17Waning Gibbous3Tue
4Wed6:436.39:268.12:085.51:40-1.05:179:17Waning Gibbous4Wed
5Thu7:365.810:027.93:125.02:24-0.15:179:17Waning Gibbous5Thu
6Fri8:345.210:357.74:164.53:080.95:189:16Third Quarter6Fri
7Sat9:424.711:067.65:173.93:542.05:199:16Third Quarter7Sat
8Sun11:104.411:367.46:133.24:433.15:209:15Third Quarter8Sun
9Mon1:324.57:032.45:394.15:219:14Third Quarter9Mon
10Tue12:077.33:175.17:461.76:455.05:229:14Waning Crescent10Tue
11Wed12:407.14:235.78:241.07:535.65:239:13Waning Crescent11Wed
12Thu1:157.15:086.38:590.38:546.05:249:12Waning Crescent12Thu
13Fri1:537.05:446.89:33-0.39:456.25:259:12Waning Crescent13Fri
14Sat2:347.06:157.110:07-0.910:296.35:269:11New Moon14Sat
15Sun3:167.06:447.410:43-1.311:106.25:279:10New Moon15Sun
16Mon4:017.07:137.611:19-1.711:516.05:289:09New Moon16Mon
17Tue4:487.07:437.811:58-1.85:299:08New Moon17Tue
18Wed5:386.88:157.912:375.712:39-1.65:309:07Waxing Crescent18Wed
19Thu6:316.58:488.01:275.31:21-1.25:319:06Waxing Crescent19Thu
20Fri7:306.19:238.12:224.62:05-0.55:329:05Waxing Crescent20Fri
21Sat8:355.69:598.03:203.92:510.55:349:04Waxing Crescent21Sat
22Sun9:515.210:368.04:202.93:401.75:359:03First Quarter22Sun
23Mon11:254.911:167.95:212.04:343.05:369:02First Quarter23Mon
24Tue1:245.16:221.05:384.25:379:00First Quarter24Tue
25Wed3:025.77:200.16:525.15:388:59Waxing Gibbous25Wed
26Thu12:437.74:116.58:14-0.78:085.75:408:58Waxing Gibbous26Thu
27Fri1:327.55:037.19:04-1.39:165.95:418:57Waxing Gibbous27Fri
28Sat2:247.45:477.59:50-1.610:145.85:428:55Full Moon28Sat
29Sun3:177.26:267.810:33-1.711:055.65:448:54Full Moon29Sun
30Mon4:107.17:027.911:15-1.511:545.35:458:53Full Moon30Mon
31Tue5:006.97:367.911:55-1.25:468:51Full Moon31Tue
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 11:22 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 74% 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 Waning Gibbous (74% 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