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

TIDE TIMES for Tuesday, June 30, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 1h 59m at 11:45 am (-1.6 ft)
Next high tide : 8:10 pm (7.9 ft)
Sunset today : 9:18 pm
Sunrise tomorrow : 5:14 am
Moon phase : Full Moon (99% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Oct 2045

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun10:236.97:116.82:21-0.82:436.57:136:50Waning Gibbous1Sun
2Mon11:497.07:096.73:12-0.93:537.07:146:48Third Quarter2Mon
3Tue1:117.14:11-0.75:407.07:166:46Third Quarter3Tue
4Wed2:087.35:17-0.57:406.67:176:44Third Quarter4Wed
5Thu2:487.46:27-0.28:245.87:196:42Waning Crescent5Thu
6Fri12:155.93:197.57:330.19:004.77:206:40Waning Crescent6Fri
7Sat1:516.03:457.68:310.69:373.37:216:38Waning Crescent7Sat
8Sun3:196.34:107.79:231.310:141.97:236:36Waning Crescent8Sun
9Mon4:346.74:347.810:102.210:520.57:246:34New Moon9Mon
10Tue5:417.14:587.810:553.311:31-0.67:266:32New Moon10Tue
11Wed6:437.45:247.811:424.37:276:30New Moon11Wed
12Thu7:427.75:527.612:11-1.412:315.37:296:28Waxing Crescent12Thu
13Fri8:437.86:217.312:53-1.71:266.07:306:26Waxing Crescent13Fri
14Sat9:467.86:526.91:36-1.62:326.67:326:24Waxing Crescent14Sat
15Sun10:547.77:266.52:22-1.24:016.87:336:22First Quarter15Sun
16Mon12:037.73:13-0.66:466.57:356:20First Quarter16Mon
17Tue1:057.64:100.28:096.07:366:18First Quarter17Tue
18Wed1:567.65:140.98:475.47:386:16First Quarter18Wed
19Thu2:357.56:221.59:124.87:396:14First Quarter19Thu
20Fri12:345.03:047.47:252.19:314.07:416:13Waxing Gibbous20Fri
21Sat2:145.23:237.38:182.69:483.27:436:11Waxing Gibbous21Sat
22Sun3:325.53:357.29:033.210:062.37:446:09Waxing Gibbous22Sun
23Mon4:316.03:477.29:423.810:271.37:466:07Waxing Gibbous23Mon
24Tue5:216.54:037.310:194.410:510.37:476:05Full Moon24Tue
25Wed6:076.94:237.310:565.111:19-0.57:496:04Full Moon25Wed
26Thu6:527.34:457.311:345.811:51-1.27:506:02Full Moon26Thu
27Fri7:387.65:077.212:146.37:526:00Waning Gibbous27Fri
28Sat8:277.85:257.212:27-1.712:586.87:535:58Waning Gibbous28Sat
29Sun9:217.95:337.11:08-1.91:517.27:555:57Waning Gibbous29Sun
30Mon10:207.95:386.91:55-1.82:587.37:575:55Waning Gibbous30Mon
31Tue11:227.95:526.62:47-1.54:347.27:585:53Third Quarter31Tue
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 3:57 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 99% 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 Full Moon (99% 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