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

TIDE TIMES for Saturday, August 1, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 3h 38m at 1:08 pm (-0.1 ft)
Next high tide : 8:25 pm (7.8 ft)
Sunset today : 8:50 pm
Sunrise tomorrow : 5:47 am
Moon phase : Waning Gibbous (90% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Jan 1974

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue9:498.211:134.82:393.45:062.58:054:27First Quarter1Tue
2Wed10:208.13:204.65:521.48:044:28First Quarter2Wed
3Thu1:505.410:53 AM8.14:195.86:380.28:044:29Waxing Gibbous3Thu
4Fri3:126.311:29 AM8.15:466.77:25-0.98:044:30Waxing Gibbous4Fri
5Sat3:587.212:138.27:097.38:11-1.88:044:31Waxing Gibbous5Sat
6Sun5:367.82:048.39:177.49:58-2.59:045:32Waxing Gibbous6Sun
7Mon6:128.33:038.210:167.310:44-2.89:035:34Full Moon7Mon
8Tue6:478.64:058.111:117.011:30-2.89:035:35Full Moon8Tue
9Wed7:218.85:077.812:076.49:035:36Full Moon9Wed
10Thu7:568.96:117.412:16-2.31:065.79:025:37Waning Gibbous10Thu
11Fri8:309.07:156.71:01-1.42:084.99:025:39Waning Gibbous11Fri
12Sat9:038.98:256.01:46-0.23:123.99:015:40Waning Gibbous12Sat
13Sun9:378.89:485.42:311.24:153.09:015:41Third Quarter13Sun
14Mon10:108.611:415.23:182.75:182.19:005:43Third Quarter14Mon
15Tue10:438.44:074.26:181.38:595:44Third Quarter15Tue
16Wed1:485.611:18 AM8.05:075.57:150.78:595:45Third Quarter16Wed
17Thu3:246.411:55 AM7.76:296.58:060.38:585:47Waning Crescent17Thu
18Fri4:267.112:377.58:037.18:520.08:575:48Waning Crescent18Fri
19Sat5:127.71:247.39:277.29:32-0.38:565:50Waning Crescent19Sat
20Sun5:498.02:157.210:267.110:09-0.48:555:51Waning Crescent20Sun
21Mon6:208.13:067.111:056.910:44-0.58:545:53New Moon21Mon
22Tue6:488.23:557.111:386.611:17-0.48:535:54New Moon22Tue
23Wed7:128.24:437.012:116.38:525:56New Moon23Wed
24Thu7:328.25:306.812:455.88:515:57New Moon24Thu
25Fri7:498.26:176.512:220.11:235.38:505:59Waxing Crescent25Fri
26Sat8:098.27:086.212:540.62:024.68:496:01Waxing Crescent26Sat
27Sun8:318.28:035.91:271.32:433.98:486:02Waxing Crescent27Sun
28Mon8:578.29:065.51:592.23:263.18:476:04Waxing Crescent28Mon
29Tue9:248.110:225.32:333.24:132.28:456:05First Quarter29Tue
30Wed9:538.03:084.35:031.48:446:07First Quarter30Wed
31Thu12:115.310:25 AM7.93:475.45:590.68:436:09First Quarter31Thu
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 4:46 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 90% 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 Gibbous (90% 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