Tides Today & Tomorrow in Upper Guadalupe Slough, CA

TIDE TIMES for Tuesday, August 18, 2026
The tide is currently rising in Upper Guadalupe Slough, CA.
Next low tide : 11:52 am (2.6 ft)
Next high tide : in 1h 00m at 5:46 am (6.9 ft)
Sunset today : 7:56 pm
Sunrise tomorrow : 6:27 am
Moon phase : First Quarter (37% illuminated)
Tide Station Location : Station #9414549
Common Questions About Tides

Upper Guadalupe Slough, CA Tides - Jan 1930

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed2:407.812:419.97:523.88:42-0.67:225:00New Moon1Wed
2Thu3:127.71:189.68:303.79:15-0.57:225:01Waxing Crescent2Thu
3Fri3:447.71:559.19:113.69:49-0.37:225:02Waxing Crescent3Fri
4Sat4:157.82:368.59:593.510:240.07:225:03Waxing Crescent4Sat
5Sun4:487.93:237.810:553.311:000.57:235:03Waxing Crescent5Sun
6Mon5:228.24:217.012:003.07:235:04First Quarter6Mon
7Tue5:578.65:416.21:112.57:235:05First Quarter7Tue
8Wed6:359.07:235.912:261.72:181.87:225:06First Quarter8Wed
9Thu7:159.69:056.11:182.43:161.07:225:07First Quarter9Thu
10Fri7:5910.110:256.72:183.04:090.17:225:08Waxing Gibbous10Fri
11Sat8:4610.711:267.43:203.44:59-0.77:225:09Waxing Gibbous11Sat
12Sun9:3611.34:203.65:48-1.37:225:10Waxing Gibbous12Sun
13Mon12:167.910:28 AM11.75:163.76:36-1.87:225:11Full Moon13Mon
14Tue1:028.211:21 AM11.96:113.57:24-2.07:215:12Full Moon14Tue
15Wed1:458.512:1311.97:053.38:10-2.07:215:13Full Moon15Wed
16Thu2:278.71:0611.58:003.08:56-1.77:215:14Waning Gibbous16Thu
17Fri3:088.92:0010.78:582.79:40-1.27:205:15Waning Gibbous17Fri
18Sat3:499.12:569.610:002.410:24-0.57:205:16Waning Gibbous18Sat
19Sun4:319.33:598.311:082.111:090.47:205:17Waning Gibbous19Sun
20Mon5:149.55:137.112:221.87:195:18Third Quarter20Mon
21Tue5:599.76:456.31:371.47:195:19Third Quarter21Tue
22Wed6:469.88:316.212:512.22:480.97:185:20Third Quarter22Wed
23Thu7:349.910:006.71:542.93:500.47:185:21Waning Crescent23Thu
24Fri8:239.911:047.23:023.44:430.07:175:23Waning Crescent24Fri
25Sat9:1010.011:527.64:053.75:29-0.27:165:24Waning Crescent25Sat
26Sun9:5510.05:003.86:08-0.47:165:25Waning Crescent26Sun
27Mon12:317.810:37 AM10.15:463.76:44-0.57:155:26New Moon27Mon
28Tue1:057.911:16 AM10.16:263.67:17-0.67:145:27New Moon28Tue
29Wed1:347.911:54 AM10.07:033.47:48-0.67:145:28New Moon29Wed
30Thu2:017.912:309.87:373.28:17-0.57:135:29New Moon30Thu
31Fri2:267.91:069.58:123.08:45-0.37:125:30New Moon31Fri
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 8:49 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 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 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 First Quarter (37% 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