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

TIDE TIMES for Thursday, July 30, 2026
The tide is currently falling in Roche Harbor, San Juan Island, WA.
Next low tide : in 2h 54m at 12:17 am (6.1 ft)
Next high tide : 4:44 am (6.7 ft)
Sunset today : 8:54 pm
Sunrise tomorrow : 5:43 am
Moon phase : Full Moon (100% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Jul 2082

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed8:285.310:268.24:034.73:040.25:159:18First Quarter1Wed
2Thu9:564.710:558.25:003.43:481.65:159:18First Quarter2Thu
3Fri11:484.511:248.15:552.04:353.25:169:17First Quarter3Fri
4Sat2:085.06:470.65:334.85:179:17First Quarter4Sat
5Sun3:516.07:37-0.76:476.15:189:16Waxing Gibbous5Sun
6Mon12:298.04:556.98:26-1.78:096.95:189:16Waxing Gibbous6Mon
7Tue1:087.95:437.69:13-2.49:237.25:199:15Waxing Gibbous7Tue
8Wed1:537.76:258.09:59-2.810:267.25:209:15Full Moon8Wed
9Thu2:457.57:038.210:43-2.811:227.05:219:14Full Moon9Thu
10Fri3:427.37:408.211:27-2.65:229:14Full Moon10Fri
11Sat4:397.08:148.112:166.712:10-2.25:239:13Full Moon11Sat
12Sun5:346.78:458.01:116.212:52-1.55:249:12Waning Gibbous12Sun
13Mon6:296.29:137.92:075.61:32-0.65:259:11Waning Gibbous13Mon
14Tue7:275.79:377.83:034.92:120.45:269:11Waning Gibbous14Tue
15Wed8:305.19:587.63:574.12:501.65:279:10Waning Gibbous15Wed
16Thu9:464.610:197.54:473.23:272.95:289:09Third Quarter16Thu
17Fri11:404.510:417.35:352.44:044.25:299:08Third Quarter17Fri
18Sat2:395.06:201.64:485.45:309:07Third Quarter18Sat
19Sun4:225.87:050.86:096.35:319:06Third Quarter19Sun
20Mon5:056.57:490.17:516.95:339:05Waning Crescent20Mon
21Tue12:086.95:377.08:32-0.59:097.25:349:04Waning Crescent21Tue
22Wed12:486.96:057.49:14-1.09:597.35:359:03Waning Crescent22Wed
23Thu1:377.06:307.69:55-1.510:367.25:369:01Waning Crescent23Thu
24Fri2:327.16:557.710:35-1.911:106.95:379:00New Moon24Fri
25Sat3:307.17:187.811:16-2.111:496.55:398:59New Moon25Sat
26Sun4:287.17:427.911:56-2.15:408:58New Moon26Sun
27Mon5:286.98:068.012:345.812:36-1.65:418:56Waxing Crescent27Mon
28Tue6:316.58:328.11:255.01:16-0.85:428:55Waxing Crescent28Tue
29Wed7:386.08:588.12:183.91:570.45:448:54Waxing Crescent29Wed
30Thu8:535.59:268.13:132.62:381.85:458:52First Quarter30Thu
31Fri10:245.19:568.04:091.43:223.45:468:51First Quarter31Fri
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 2:30 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 spring phase. Tonight's moon is 100% 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 (100% 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