Tides Today & Tomorrow in Upper Guadalupe Slough, CA

TIDE TIMES for Monday, August 17, 2026
The tide is currently falling in Upper Guadalupe Slough, CA.
Next low tide (tomorrow) : in 3h 30m at 12:22 am (1.3 ft)
Next high tide (tomorrow) : 5:46 am (6.9 ft)
Sunset today : 7:57 pm
Sunrise tomorrow : 6:26 am
Moon phase : Waxing Crescent (28% illuminated)
Tide Station Location : Station #9414549
Common Questions About Tides

Upper Guadalupe Slough, CA Tides - Sep 1930

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Mon9:217.47:239.52:460.52:323.95:376:38First Quarter1Mon
2Tue10:187.88:259.53:480.43:413.85:386:36Waxing Gibbous2Tue
3Wed11:008.09:209.64:400.24:353.65:396:35Waxing Gibbous3Wed
4Thu11:358.210:089.75:230.15:193.35:406:33Waxing Gibbous4Thu
5Fri12:048.26:000.05:573.05:416:32Waxing Gibbous5Fri
6Sat12:298.26:320.16:322.75:426:30Full Moon6Sat
7Sun12:528.47:010.27:052.45:426:29Full Moon7Sun
8Mon12:089.41:138.57:270.47:382.15:436:27Full Moon8Mon
9Tue12:469.01:358.87:530.78:121.85:446:26Full Moon9Tue
10Wed1:268.61:589.08:201.18:481.55:456:24Waning Gibbous10Wed
11Thu2:108.12:239.28:471.79:281.35:466:23Waning Gibbous11Thu
12Fri2:597.62:529.49:172.310:141.15:476:21Waning Gibbous12Fri
13Sat4:007.03:269.59:522.911:090.95:476:20Waning Gibbous13Sat
14Sun5:216.64:109.510:343.55:486:18Third Quarter14Sun
15Mon7:046.65:089.512:160.711:37 AM3.95:496:17Third Quarter15Mon
16Tue8:366.96:199.61:310.51:094.15:506:15Third Quarter16Tue
17Wed9:357.47:339.92:450.12:383.95:516:13Waning Crescent17Wed
18Thu10:177.98:4310.23:48-0.33:453.55:526:12Waning Crescent18Thu
19Fri10:538.49:4610.64:41-0.64:412.85:526:10Waning Crescent19Fri
20Sat11:278.810:4410.65:27-0.75:332.15:536:09Waning Crescent20Sat
21Sun12:019.36:10-0.56:231.45:546:07New Moon21Sun
22Mon12:349.86:50-0.27:120.85:556:06New Moon22Mon
23Tue12:3610.01:0710.27:290.48:020.35:566:04New Moon23Tue
24Wed1:339.41:4210.48:081.18:520.05:576:03Waxing Crescent24Wed
25Thu2:328.72:1710.48:491.99:440.05:576:01Waxing Crescent25Thu
26Fri3:368.02:5510.29:322.710:390.15:586:00Waxing Crescent26Fri
27Sat4:497.53:399.810:233.411:410.35:595:58First Quarter27Sat
28Sun6:167.34:309.211:323.96:005:57First Quarter28Sun
29Mon7:467.45:348.812:510.51:044.16:015:55First Quarter29Mon
30Tue8:547.76:478.52:030.62:283.96:025:53First Quarter30Tue
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (9414549)

Common Questions About Upper Guadalupe Slough, CA Tides

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What time does the tide turn (slack tide) in Upper Guadalupe Slough, CA today?

Slack tide in Upper Guadalupe Slough, CA is approximately 3:04 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 Upper Guadalupe Slough, CA?

Upper Guadalupe Slough, CA 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 Upper Guadalupe Slough, CA 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 Upper Guadalupe Slough, CA?

Tide predictions for Upper Guadalupe Slough, CA 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 Upper Guadalupe Slough, CA?

Tide data for Upper Guadalupe Slough, CA is sourced from NOAA Station #9414549. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=9414549.

What is the moon phase in Upper Guadalupe Slough, CA tonight?

Tonight the moon over Upper Guadalupe Slough, CA is Waxing Crescent (28% illuminated). This places Upper Guadalupe Slough, CA 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