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

TIDE TIMES for Monday, August 3, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 33m at 2:58 am (3.1 ft)
Next high tide : 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 - Apr 1971

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Thu7:226.911:477.32:536.63:04-0.85:506:42First Quarter1Thu
2Fri8:096.44:436.74:07-0.15:486:43First Quarter2Fri
3Sat12:567.49:17 AM5.87:196.35:160.55:466:45First Quarter3Sat
4Sun1:497.410:50 AM5.58:175.66:261.05:446:46Waxing Gibbous4Sun
5Mon2:307.412:345.38:505.07:261.55:426:48Waxing Gibbous5Mon
6Tue3:017.32:045.59:124.38:141.95:406:49Waxing Gibbous6Tue
7Wed3:247.23:105.89:293.58:542.45:386:51Waxing Gibbous7Wed
8Thu3:397.14:046.19:482.79:303.05:366:52Full Moon8Thu
9Fri3:497.14:516.410:091.810:053.75:346:54Full Moon9Fri
10Sat4:017.15:356.610:331.010:404.45:326:55Full Moon10Sat
11Sun4:197.16:196.911:010.211:165.05:306:57Full Moon11Sun
12Mon4:417.07:047.011:31-0.311:555.65:286:58Full Moon12Mon
13Tue5:066.97:537.112:06-0.85:267:00Waning Gibbous13Tue
14Wed5:296.88:487.212:386.112:44-1.05:247:01Waning Gibbous14Wed
15Thu5:486.79:547.11:266.61:29-1.05:227:03Waning Gibbous15Thu
16Fri5:536.611:057.22:266.92:19-0.95:207:04Third Quarter16Fri
17Sat5:556.43:487.03:16-0.65:187:05Third Quarter17Sat
18Sun12:067.26:27 AM6.15:366.74:18-0.35:167:07Third Quarter18Sun
19Mon12:517.39:49 AM5.76:446.05:230.25:147:08Third Quarter19Mon
20Tue1:257.411:35 AM5.57:205.06:260.85:127:10Waning Crescent20Tue
21Wed1:527.51:145.67:563.67:231.55:107:11Waning Crescent21Wed
22Thu2:187.62:446.08:332.08:162.45:087:13Waning Crescent22Thu
23Fri2:437.73:596.69:110.49:053.45:077:14New Moon23Fri
24Sat3:097.85:047.29:51-1.09:544.45:057:16New Moon24Sat
25Sun4:387.97:037.611:31-2.011:445.36:038:17New Moon25Sun
26Mon5:097.88:017.912:14-2.66:018:19New Moon26Mon
27Tue5:427.68:598.012:376.012:58-2.75:598:20Waxing Crescent27Tue
28Wed6:187.39:597.91:376.51:45-2.35:588:22Waxing Crescent28Wed
29Thu6:586.811:027.82:496.72:35-1.75:568:23Waxing Crescent29Thu
30Fri7:436.34:256.63:28-0.85:548:25First Quarter30Fri
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 5:42 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