Tides Today & Tomorrow in Knappa, Knappa Slough, OR

TIDE TIMES for Tuesday, August 18, 2026
The tide is currently falling in Knappa, Knappa Slough, OR.
Next low tide : in 1h 28m at 12:57 am (0.4 ft)
Next high tide : 6:35 am (6.1 ft)
Sunset today : 8:20 pm
Sunrise tomorrow : 6:16 am
Moon phase : Waxing Crescent (28% illuminated)
Tide Station Location : Station #9439069
Common Questions About Tides

Knappa, Knappa Slough, OR Tides - Aug 2048

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat8:005.77:497.62:230.81:531.85:578:43Third Quarter1Sat
2Sun9:125.48:407.43:280.82:492.45:588:42Third Quarter2Sun
3Mon10:275.49:387.34:360.73:562.86:008:40Waning Crescent3Mon
4Tue11:345.710:387.35:400.55:042.86:018:39Waning Crescent4Tue
5Wed12:296.16:340.16:052.76:028:38Waning Crescent5Wed
6Thu1:156.47:20-0.26:592.46:038:36Waning Crescent6Thu
7Fri12:237.71:546.78:00-0.47:472.16:048:35New Moon7Fri
8Sat1:077.82:307.08:37-0.68:311.86:068:33New Moon8Sat
9Sun1:497.93:027.29:11-0.79:121.56:078:32New Moon9Sun
10Mon2:297.93:317.49:43-0.79:521.16:088:30New Moon10Mon
11Tue3:097.83:597.610:13-0.510:300.86:098:28Waxing Crescent11Tue
12Wed3:507.64:277.810:43-0.311:090.56:118:27Waxing Crescent12Wed
13Thu4:337.34:568.111:130.111:510.36:128:25Waxing Crescent13Thu
14Fri5:216.85:308.311:460.56:138:24Waxing Crescent14Fri
15Sat6:176.36:118.312:380.312:251.16:148:22First Quarter15Sat
16Sun7:245.87:008.31:350.31:121.76:168:20First Quarter16Sun
17Mon8:455.58:028.12:470.32:162.36:178:19First Quarter17Mon
18Tue10:095.59:168.14:080.23:392.56:188:17Waxing Gibbous18Tue
19Wed11:235.910:328.25:23-0.25:022.56:198:15Waxing Gibbous19Wed
20Thu12:236.56:26-0.66:132.06:218:13Waxing Gibbous20Thu
21Fri1:127.07:20-1.07:151.56:228:12Waxing Gibbous21Fri
22Sat12:428.61:567.58:08-1.18:100.96:238:10Full Moon22Sat
23Sun1:368.62:377.98:51-1.19:010.56:248:08Full Moon23Sun
24Mon2:278.53:158.19:31-1.09:490.16:268:06Full Moon24Mon
25Tue3:158.23:508.210:08-0.610:35-0.16:278:04Waning Gibbous25Tue
26Wed4:027.74:258.210:43-0.111:18-0.16:288:03Waning Gibbous26Wed
27Thu4:507.24:578.111:170.56:298:01Waning Gibbous27Thu
28Fri5:386.75:307.912:010.011:51 AM1.16:317:59Waning Gibbous28Fri
29Sat6:316.16:067.612:460.212:271.76:327:57Third Quarter29Sat
30Sun7:305.76:477.31:370.51:092.26:337:55Third Quarter30Sun
31Mon8:395.47:407.02:370.82:062.76:357:53Third Quarter31Mon
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 3:46 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 Knappa, Knappa Slough, OR?

Knappa, Knappa Slough, OR is currently in a transitional phase. Tonight's moon is 28% 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 Waxing Crescent (28% 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