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

TIDE TIMES for Monday, July 13, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 10:44 pm (7.2 ft)
Next high tide : in 27m at 6:45 pm (8.1 ft)
Sunset today : 9:12 pm
Sunrise tomorrow : 5:24 am
Moon phase : New Moon (1% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Sep 1993

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed5:226.46:267.211:331.36:307:54Full Moon1Wed
2Thu6:086.46:427.112:073.012:072.06:317:52Full Moon2Thu
3Fri6:536.47:017.112:402.412:422.66:337:50Waning Gibbous3Fri
4Sat7:406.37:257.01:161.81:193.46:347:48Waning Gibbous4Sat
5Sun8:306.27:536.91:531.41:574.16:357:46Waning Gibbous5Sun
6Mon9:286.08:236.72:341.12:384.86:377:44Waning Gibbous6Mon
7Tue10:385.98:566.63:180.93:255.56:387:42Third Quarter7Tue
8Wed12:166.04:080.74:276.06:407:40Third Quarter8Wed
9Thu1:526.25:040.65:536.36:417:38Third Quarter9Thu
10Fri2:496.56:070.57:186.26:427:36Third Quarter10Fri
11Sat3:266.87:090.38:155.86:447:33Waning Crescent11Sat
12Sun12:426.33:557.08:070.18:595.26:457:31Waning Crescent12Sun
13Mon1:566.44:207.28:580.09:384.26:477:29Waning Crescent13Mon
14Tue3:076.74:467.49:450.110:183.16:487:27New Moon14Tue
15Wed4:146.95:127.610:290.611:001.96:497:25New Moon15Wed
16Thu5:187.15:417.711:131.311:440.76:517:23New Moon16Thu
17Fri6:207.26:127.811:582.26:527:21Waxing Crescent17Fri
18Sat7:237.36:467.812:30-0.212:453.26:547:19Waxing Crescent18Sat
19Sun8:287.27:237.71:19-0.81:354.26:557:16Waxing Crescent19Sun
20Mon9:397.18:037.42:10-1.12:325.06:567:14Waxing Crescent20Mon
21Tue10:587.08:487.03:05-1.03:415.76:587:12First Quarter21Tue
22Wed12:207.04:04-0.65:095.96:597:10First Quarter22Wed
23Thu1:337.15:080.06:595.87:017:08First Quarter23Thu
24Fri2:317.36:180.58:275.37:027:06Waxing Gibbous24Fri
25Sat12:155.73:177.37:271.09:174.67:047:04Waxing Gibbous25Sat
26Sun1:475.73:547.38:271.49:514.07:057:02Waxing Gibbous26Sun
27Mon3:065.84:247.29:161.810:173.37:067:00Waxing Gibbous27Mon
28Tue4:076.14:467.19:572.210:412.67:086:57Full Moon28Tue
29Wed4:586.35:027.010:342.711:061.97:096:55Full Moon29Wed
30Thu5:436.65:167.011:093.311:341.37:116:53Full Moon30Thu
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 8:44 pm — 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 1% 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 New Moon (1% 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