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 7h 08m 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 - Jul 2045

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat5:086.68:537.91:216.612:44-1.35:149:18Waning Gibbous1Sat
2Sun5:576.39:197.82:106.31:21-0.95:159:18Waning Gibbous2Sun
3Mon6:495.99:417.83:025.81:58-0.25:169:17Waning Gibbous3Mon
4Tue7:455.410:017.73:525.12:330.65:179:17Waning Gibbous4Tue
5Wed8:494.910:237.74:404.33:071.75:179:16Third Quarter5Wed
6Thu10:074.410:477.65:233.43:402.85:189:16Third Quarter6Thu
7Fri11:494.311:127.56:042.44:134.05:199:15Third Quarter7Fri
8Sat2:494.86:451.34:535.25:209:15Third Quarter8Sat
9Sun4:305.87:270.26:126.35:219:14Waning Crescent9Sun
10Mon12:067.55:116.68:10-0.97:457.05:229:14Waning Crescent10Mon
11Tue12:387.55:457.28:55-1.88:577.45:239:13Waning Crescent11Tue
12Wed1:197.76:187.79:40-2.69:557.45:249:12Waning Crescent12Wed
13Thu2:137.76:508.010:27-3.110:477.25:259:11New Moon13Thu
14Fri3:177.87:238.111:14-3.311:406.85:269:11New Moon14Fri
15Sat4:247.67:558.212:01-3.15:279:10New Moon15Sat
16Sun5:327.38:278.312:386.112:47-2.55:289:09Waxing Crescent16Sun
17Mon6:406.78:588.31:405.31:33-1.55:299:08Waxing Crescent17Mon
18Tue7:516.09:288.32:454.22:18-0.15:309:07Waxing Crescent18Tue
19Wed9:125.39:598.23:493.03:031.55:319:06First Quarter19Wed
20Thu10:544.910:298.04:511.83:503.25:329:05First Quarter20Thu
21Fri1:055.15:510.84:454.85:349:04First Quarter21Fri
22Sat2:575.96:480.05:586.05:359:03First Quarter22Sat
23Sun4:116.77:41-0.67:346.85:369:01Waxing Gibbous23Sun
24Mon12:137.25:027.38:31-1.09:107.05:379:00Waxing Gibbous24Mon
25Tue12:577.05:427.79:17-1.210:216.95:388:59Waxing Gibbous25Tue
26Wed1:496.86:187.89:58-1.211:046.75:408:58Waxing Gibbous26Wed
27Thu2:446.76:497.810:37-1.211:366.55:418:56Full Moon27Thu
28Fri3:376.77:177.711:14-1.15:428:55Full Moon28Fri
29Sat4:286.67:407.612:076.111:49 AM-0.95:448:54Full Moon29Sat
30Sun5:166.47:597.612:425.712:22-0.55:458:52Full Moon30Sun
31Mon6:046.28:167.61:205.212:550.15:468:51Waning Gibbous31Mon
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