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

TIDE TIMES for Thursday, July 30, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide (tomorrow) : 12:53 am (5.6 ft)
Next high tide : in 5h 09m at 7:46 pm (7.7 ft)
Sunset today : 8:53 pm
Sunrise tomorrow : 5:44 am
Moon phase : Full Moon (99% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Jun 1977

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed3:447.96:427.810:54-2.711:125.65:149:06Full Moon1Wed
2Thu4:297.87:308.111:39-3.15:139:07Full Moon2Thu
3Fri5:177.68:188.312:095.812:25-3.05:139:08Waning Gibbous3Fri
4Sat6:097.29:068.31:115.81:14-2.65:129:09Waning Gibbous4Sat
5Sun7:056.69:538.32:205.62:03-1.85:119:10Waning Gibbous5Sun
6Mon8:056.010:408.23:375.12:54-0.85:119:10Waning Gibbous6Mon
7Tue9:155.311:258.04:594.53:460.45:119:11Third Quarter7Tue
8Wed10:414.76:163.64:411.75:109:12Third Quarter8Wed
9Thu12:087.912:394.57:192.75:392.95:109:13Third Quarter9Thu
10Fri12:467.72:324.98:081.96:444.05:109:13Waning Crescent10Fri
11Sat1:207.53:535.58:471.17:514.95:099:14Waning Crescent11Sat
12Sun1:507.34:526.29:190.48:535.55:099:15Waning Crescent12Sun
13Mon2:197.15:406.79:49-0.29:485.95:099:15Waning Crescent13Mon
14Tue2:497.06:197.110:18-0.610:366.15:099:16New Moon14Tue
15Wed3:216.96:547.410:49-0.911:216.25:099:16New Moon15Wed
16Thu3:576.97:267.611:20-1.15:099:17New Moon16Thu
17Fri4:366.77:567.712:036.311:54 AM-1.25:099:17New Moon17Fri
18Sat5:166.68:257.812:476.212:29-1.25:099:17Waxing Crescent18Sat
19Sun5:596.38:547.81:356.11:06-1.05:099:18Waxing Crescent19Sun
20Mon6:446.09:247.92:255.81:44-0.75:099:18Waxing Crescent20Mon
21Tue7:355.69:577.93:195.42:24-0.15:109:18Waxing Crescent21Tue
22Wed8:345.210:307.94:124.83:050.65:109:18First Quarter22Wed
23Thu9:454.811:047.95:044.03:501.55:109:19First Quarter23Thu
24Fri11:114.511:407.95:553.04:402.55:109:19First Quarter24Fri
25Sat12:564.66:451.95:393.65:119:19First Quarter25Sat
26Sun12:177.92:485.27:330.66:464.65:119:19Waxing Gibbous26Sun
27Mon12:567.94:056.08:20-0.67:565.35:129:19Waxing Gibbous27Mon
28Tue1:387.95:026.89:06-1.69:015.75:129:19Waxing Gibbous28Tue
29Wed2:247.95:507.49:51-2.410:015.95:139:18Full Moon29Wed
30Thu3:147.96:347.810:37-2.810:585.95:139:18Full Moon30Thu
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 10:19 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