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

TIDE TIMES for Saturday, July 11, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 8:45 am (-2.3 ft)
Next high tide : in 1h 56m at 12:36 am (7.9 ft)
Sunset today : 9:14 pm
Sunrise tomorrow : 5:21 am
Moon phase : Waning Crescent (18% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Aug 1997

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri2:586.86:087.510:16-0.910:535.75:478:50New Moon1Fri
2Sat3:476.76:417.610:53-0.811:335.45:488:48New Moon2Sat
3Sun4:326.67:107.611:29-0.65:508:47New Moon3Sun
4Mon5:176.57:357.512:125.112:06-0.35:518:45New Moon4Mon
5Tue6:016.37:587.512:514.812:420.25:528:44Waxing Crescent5Tue
6Wed6:476.18:207.41:324.31:180.85:548:42Waxing Crescent6Wed
7Thu7:355.88:457.42:153.91:551.55:558:41Waxing Crescent7Thu
8Fri8:285.59:147.33:003.42:332.25:568:39Waxing Crescent8Fri
9Sat9:285.29:467.23:462.93:123.15:588:37First Quarter9Sat
10Sun10:415.010:217.14:342.43:554.05:598:36First Quarter10Sun
11Mon12:225.05:251.84:484.86:008:34First Quarter11Mon
12Tue2:245.46:181.25:595.46:028:32First Quarter12Tue
13Wed3:336.07:110.57:165.86:038:31Waxing Gibbous13Wed
14Thu12:296.94:176.58:03-0.18:225.96:058:29Waxing Gibbous14Thu
15Fri1:237.04:536.98:52-0.89:165.76:068:27Waxing Gibbous15Fri
16Sat2:207.15:257.39:38-1.310:045.36:078:25Waxing Gibbous16Sat
17Sun3:207.35:577.510:24-1.510:504.76:098:23Full Moon17Sun
18Mon4:207.36:297.711:09-1.411:384.06:108:21Full Moon18Mon
19Tue5:197.37:017.911:53-1.06:128:20Full Moon19Tue
20Wed6:207.17:367.912:283.212:39-0.36:138:18Waning Gibbous20Wed
21Thu7:226.88:117.91:212.41:260.76:148:16Waning Gibbous21Thu
22Fri8:286.48:497.82:171.72:151.96:168:14Waning Gibbous22Fri
23Sat9:436.09:297.63:151.13:083.16:178:12Third Quarter23Sat
24Sun11:155.810:127.34:150.74:084.26:198:10Third Quarter24Sun
25Mon12:576.05:180.55:225.06:208:08Third Quarter25Mon
26Tue2:236.46:230.36:515.56:218:06Third Quarter26Tue
27Wed3:276.87:270.38:215.66:238:04Waning Crescent27Wed
28Thu1:006.44:167.18:250.29:285.46:248:02Waning Crescent28Thu
29Fri2:056.34:577.39:140.210:125.16:268:00Waning Crescent29Fri
30Sat3:056.35:307.39:560.310:444.76:277:58Waning Crescent30Sat
31Sun3:566.45:587.310:340.511:134.36:287:56New Moon31Sun
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 4:40 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 spring phase. Tonight's moon is 18% 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 near their weekly maximum.

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 Crescent (18% illuminated). This places Roche Harbor, San Juan Island, WA in a spring tide cycle, so tidal ranges are near their weekly maximum 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