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

TIDE TIMES for Wednesday, July 22, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 6:38 am (0.8 ft)
Next high tide (tomorrow) : in 1h 22m at 10:51 pm (7.5 ft)
Sunset today : 9:04 pm
Sunrise tomorrow : 5:33 am
Moon phase : First Quarter (53% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Apr 1989

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat2:197.311:05 AM6.17:356.26:450.05:496:43Waning Crescent1Sat
2Sun3:447.41:396.19:065.38:410.26:477:44Waning Crescent2Sun
3Mon4:057.53:046.39:414.09:300.76:457:46Waning Crescent3Mon
4Tue4:277.64:216.610:182.510:161.56:437:47New Moon4Tue
5Wed4:497.85:307.010:581.011:012.56:417:49New Moon5Wed
6Thu5:147.96:357.311:39-0.411:463.76:397:50New Moon6Thu
7Fri5:428.07:397.512:23-1.56:377:52Waxing Crescent7Fri
8Sat6:127.98:447.612:334.71:08-2.06:357:53Waxing Crescent8Sat
9Sun6:447.79:537.61:265.71:56-2.16:337:55Waxing Crescent9Sun
10Mon7:197.311:077.52:276.32:47-1.86:317:56Waxing Crescent10Mon
11Tue7:586.83:446.73:42-1.16:297:58First Quarter11Tue
12Wed12:237.58:46 AM6.35:446.74:44-0.46:277:59First Quarter12Wed
13Thu1:297.59:58 AM5.78:126.15:520.46:258:01First Quarter13Thu
14Fri2:227.511:36 AM5.29:055.47:011.16:238:02First Quarter14Fri
15Sat3:047.41:295.19:394.68:031.76:218:03Waxing Gibbous15Sat
16Sun3:367.33:055.310:023.88:552.36:198:05Waxing Gibbous16Sun
17Mon3:597.24:145.610:193.09:382.96:178:06Waxing Gibbous17Mon
18Tue4:137.15:106.010:372.110:173.66:158:08Waxing Gibbous18Tue
19Wed4:237.05:586.410:581.210:544.36:138:09Full Moon19Wed
20Thu4:367.06:436.711:210.411:314.96:118:11Full Moon20Thu
21Fri4:547.07:257.011:48-0.36:098:12Full Moon21Fri
22Sat5:167.08:087.212:105.512:18-0.86:078:14Full Moon22Sat
23Sun5:406.98:547.312:516.012:52-1.16:058:15Waning Gibbous23Sun
24Mon6:036.79:457.41:376.51:30-1.36:048:17Waning Gibbous24Mon
25Tue6:166.610:447.42:296.82:13-1.26:028:18Waning Gibbous25Tue
26Wed6:046.511:467.43:357.03:02-1.06:008:20Waning Gibbous26Wed
27Thu6:026.35:086.93:56-0.75:588:21Third Quarter27Thu
28Fri12:417.44:55-0.35:578:23Third Quarter28Fri
29Sat1:237.410:29 AM5.47:505.85:580.35:558:24Third Quarter29Sat
30Sun1:557.512:195.28:104.76:591.05:538:25Waning Crescent30Sun
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 2:44 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 neap phase. Tonight's moon is 53% 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 minimum.

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 First Quarter (53% illuminated). This places Roche Harbor, San Juan Island, WA in a neap tide cycle, so tidal ranges are near their weekly minimum 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