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

TIDE TIMES for Monday, July 13, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 10:23 am (-3.4 ft)
Next high tide : in 4h 04m at 2:15 am (7.9 ft)
Sunset today : 9:12 pm
Sunrise tomorrow : 5:23 am
Moon phase : Waning Crescent (4% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Aug 1994

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Mon3:586.17:190.87:226.25:478:50Waning Crescent1Mon
2Tue12:096.84:416.58:080.48:346.35:488:49Waning Crescent2Tue
3Wed12:586.75:146.88:530.09:276.35:498:47Waning Crescent3Wed
4Thu1:506.75:417.19:33-0.410:066.15:518:46Waning Crescent4Thu
5Fri2:436.86:047.210:10-0.710:415.85:528:44New Moon5Fri
6Sat3:356.86:257.410:47-0.911:175.35:538:43New Moon6Sat
7Sun4:286.96:477.511:24-0.911:554.75:558:41New Moon7Sun
8Mon5:216.87:127.712:01-0.65:568:39New Moon8Mon
9Tue6:176.67:397.812:383.912:400.05:578:38Waxing Crescent9Tue
10Wed7:156.38:107.91:253.01:210.95:598:36Waxing Crescent10Wed
11Thu8:186.08:427.92:152.22:041.96:008:34Waxing Crescent11Thu
12Fri9:315.79:187.83:081.32:493.06:018:33First Quarter12Fri
13Sat10:595.59:577.74:050.63:414.26:038:31First Quarter13Sat
14Sun12:485.75:060.04:455.26:048:29First Quarter14Sun
15Mon2:246.16:09-0.46:065.86:068:27First Quarter15Mon
16Tue3:306.77:14-0.77:346.06:078:26Waxing Gibbous16Tue
17Wed12:357.14:207.18:14-0.98:485.86:088:24Waxing Gibbous17Wed
18Thu1:426.95:007.49:08-0.99:465.46:108:22Waxing Gibbous18Thu
19Fri2:506.95:357.59:56-0.810:344.86:118:20Full Moon19Fri
20Sat3:536.86:077.610:39-0.511:164.26:138:18Full Moon20Sat
21Sun4:506.76:357.611:190.011:573.66:148:16Full Moon21Sun
22Mon5:436.67:007.511:580.66:158:14Full Moon22Mon
23Tue6:346.47:237.412:383.012:371.46:178:13Waning Gibbous23Tue
24Wed7:256.27:467.31:202.51:172.36:188:11Waning Gibbous24Wed
25Thu8:196.08:127.12:022.01:583.16:208:09Waning Gibbous25Thu
26Fri9:185.88:416.92:461.72:424.06:218:07Waning Gibbous26Fri
27Sat10:325.79:146.73:331.43:314.86:228:05Third Quarter27Sat
28Sun12:165.74:231.34:325.56:248:03Third Quarter28Sun
29Mon1:585.95:181.25:535.96:258:01Third Quarter29Mon
30Tue3:046.26:181.07:206.16:277:59Third Quarter30Tue
31Wed3:476.57:170.88:275.96:287:57Waning Crescent31Wed
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 6:19 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 4% 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 Waning Crescent (4% 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