Tides Today & Tomorrow in Knappa, Knappa Slough, OR

TIDE TIMES for Tuesday, August 18, 2026
The tide is currently rising in Knappa, Knappa Slough, OR.
Next low tide (tomorrow) : 1:50 am (0.6 ft)
Next high tide : in 37m at 6:26 pm (7.7 ft)
Sunset today : 8:18 pm
Sunrise tomorrow : 6:17 am
Moon phase : First Quarter (37% illuminated)
Tide Station Location : Station #9439069
Common Questions About Tides

Knappa, Knappa Slough, OR Tides - Apr 2050

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri10:166.811:357.04:512.75:401.06:527:43Waxing Gibbous1Fri
2Sat11:207.05:532.26:270.96:507:44Waxing Gibbous2Sat
3Sun12:187.412:157.26:461.77:080.96:487:46Waxing Gibbous3Sun
4Mon12:557.71:037.37:311.27:450.96:477:47Waxing Gibbous4Mon
5Tue1:288.01:467.58:130.88:201.06:457:48Full Moon5Tue
6Wed1:588.22:287.58:520.48:541.16:437:50Full Moon6Wed
7Thu2:268.43:087.59:290.19:271.46:417:51Full Moon7Thu
8Fri2:538.63:487.410:05-0.110:001.66:397:52Full Moon8Fri
9Sat3:218.74:297.310:40-0.210:331.86:377:53Waning Gibbous9Sat
10Sun3:528.85:137.111:17-0.211:092.16:357:55Waning Gibbous10Sun
11Mon4:288.86:016.911:57-0.211:502.36:337:56Waning Gibbous11Mon
12Tue5:108.76:566.612:430.06:327:57Waning Gibbous12Tue
13Wed6:018.47:586.512:402.51:390.26:307:59Third Quarter13Wed
14Thu7:048.09:046.61:452.72:470.46:288:00Third Quarter14Thu
15Fri8:217.610:077.03:052.63:580.56:268:01Third Quarter15Fri
16Sat9:447.511:037.54:252.25:030.46:248:03Waning Crescent16Sat
17Sun11:007.611:538.15:361.56:000.46:228:04Waning Crescent17Sun
18Mon12:077.86:370.76:520.46:218:05Waning Crescent18Mon
19Tue12:388.71:078.07:330.07:400.56:198:07New Moon19Tue
20Wed1:209.12:028.18:24-0.68:260.86:178:08New Moon20Wed
21Thu2:019.42:548.19:13-0.99:111.16:158:09New Moon21Thu
22Fri2:419.43:448.010:00-1.09:551.46:148:11New Moon22Fri
23Sat3:219.34:347.810:46-1.010:381.76:128:12Waxing Crescent23Sat
24Sun4:019.05:247.511:30-0.711:222.16:108:13Waxing Crescent24Sun
25Mon4:418.66:147.212:14-0.36:098:15Waxing Crescent25Mon
26Tue5:258.17:076.912:082.41:000.16:078:16Waxing Crescent26Tue
27Wed6:137.58:026.812:592.61:500.66:058:17First Quarter27Wed
28Thu7:116.98:586.71:592.82:450.96:048:19First Quarter28Thu
29Fri8:216.59:536.93:082.73:431.26:028:20First Quarter29Fri
30Sat9:356.210:427.14:182.44:391.36:018:21First Quarter30Sat
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (9439069)

Common Questions About Knappa, Knappa Slough, OR Tides

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What time does the tide turn (slack tide) in Knappa, Knappa Slough, OR today?

Slack tide in Knappa, Knappa Slough, OR is approximately 10:08 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 Knappa, Knappa Slough, OR?

Knappa, Knappa Slough, OR is currently in a transitional phase. Tonight's moon is 37% 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 shifting between spring and neap.

What datum are Knappa, Knappa Slough, OR 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 Knappa, Knappa Slough, OR?

Tide predictions for Knappa, Knappa Slough, OR 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 Knappa, Knappa Slough, OR?

Tide data for Knappa, Knappa Slough, OR is sourced from NOAA Station #9439069. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=9439069.

What is the moon phase in Knappa, Knappa Slough, OR tonight?

Tonight the moon over Knappa, Knappa Slough, OR is First Quarter (37% illuminated). This places Knappa, Knappa Slough, OR in a transitional tide cycle, so tidal ranges are shifting between spring and neap 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