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

TIDE TIMES for Thursday, July 23, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 2h 21m at 7:27 am (0.2 ft)
Next high tide : 4:07 pm (6.4 ft)
Sunset today : 9:02 pm
Sunrise tomorrow : 5:35 am
Moon phase : Waxing Gibbous (72% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Feb 1987

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun7:308.76:216.612:05-0.91:134.57:425:10Waxing Crescent1Sun
2Mon7:588.67:315.912:480.42:103.57:405:12Waxing Crescent2Mon
3Tue8:248.48:565.41:291.93:052.67:395:13First Quarter3Tue
4Wed8:498.210:595.42:113.53:591.87:375:15First Quarter4Wed
5Thu9:147.92:565.04:531.17:365:16First Quarter5Thu
6Fri1:165.99:40 AM7.63:566.35:470.67:345:18First Quarter6Fri
7Sat2:486.810:10 AM7.25:397.26:400.37:335:20Waxing Gibbous7Sat
8Sun3:407.410:48 AM7.08:037.57:310.17:315:21Waxing Gibbous8Sun
9Mon4:197.811:43 AM6.89:417.38:18-0.17:305:23Waxing Gibbous9Mon
10Tue4:518.012:496.810:137.29:00-0.37:285:25Waxing Gibbous10Tue
11Wed5:198.11:516.810:256.99:37-0.47:275:26Waxing Gibbous11Wed
12Thu5:428.02:466.910:406.610:12-0.57:255:28Full Moon12Thu
13Fri6:028.03:366.911:036.210:45-0.37:235:30Full Moon13Fri
14Sat6:188.04:256.811:325.611:170.07:225:31Full Moon14Sat
15Sun6:348.05:166.612:064.97:205:33Full Moon15Sun
16Mon6:528.16:106.312:434.07:185:34Waning Gibbous16Mon
17Tue7:138.17:106.012:221.51:233.07:165:36Waning Gibbous17Tue
18Wed7:368.08:195.812:552.62:062.07:155:38Waning Gibbous18Wed
19Thu7:597.99:485.61:303.82:521.17:135:39Third Quarter19Thu
20Fri8:237.82:065.13:450.37:115:41Third Quarter20Fri
21Sat12:075.98:48 AM7.72:496.34:44-0.47:095:42Third Quarter21Sat
22Sun2:156.69:18 AM7.64:077.25:48-0.97:075:44Third Quarter22Sun
23Mon3:097.310:11 AM7.56:087.76:53-1.37:055:46Waning Crescent23Mon
24Tue3:467.811:35 AM7.47:437.67:53-1.67:035:47Waning Crescent24Tue
25Wed4:188.11:017.38:457.08:47-1.77:025:49Waning Crescent25Wed
26Thu4:488.22:207.39:336.39:36-1.57:005:50New Moon26Thu
27Fri5:168.33:307.210:195.310:20-0.96:585:52New Moon27Fri
28Sat5:428.34:357.111:044.311:020.06:565:54New Moon28Sat
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 11:47 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 72% 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 Waxing Gibbous (72% 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