Tides Today & Tomorrow in Port Isabel, TX

TIDE TIMES for Thursday, August 20, 2026
The tide is currently falling in Port Isabel, TX.
Next low tide : in 3h 50m at 4:19 pm (0.1 ft)
Next high tide (tomorrow) : 3:41 am (1.6 ft)
Sunset today : 8:00 pm
Sunrise tomorrow : 7:03 am
Moon phase : First Quarter (56% illuminated)
Tide Station Location : Station #8779770
Common Questions About Tides

Port Isabel, TX Tides - Sep 1998

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue3:501.56:160.27:087:48Waxing Gibbous1Tue
2Wed4:111.67:070.27:097:47Waxing Gibbous2Wed
3Thu4:261.68:010.27:097:46Waxing Gibbous3Thu
4Fri4:371.611:53 AM1.49:411.48:540.27:107:45Waxing Gibbous4Fri
5Sat4:501.51:331.49:531.39:440.37:107:44Full Moon5Sat
6Sun5:051.53:141.510:171.210:340.47:107:43Full Moon6Sun
7Mon5:211.44:291.510:501.011:310.67:117:42Full Moon7Mon
8Tue5:381.35:491.511:340.87:117:41Waning Gibbous8Tue
9Wed5:531.37:231.512:380.912:260.67:127:40Waning Gibbous9Wed
10Thu6:031.39:021.61:441.11:190.47:127:39Waning Gibbous10Thu
11Fri5:551.411:301.62:511.32:110.37:127:37Third Quarter11Fri
12Sat3:070.37:137:36Third Quarter12Sat
13Sun1:011.74:140.27:137:35Third Quarter13Sun
14Mon2:301.85:240.37:147:34Third Quarter14Mon
15Tue3:281.86:260.37:147:33Waning Crescent15Tue
16Wed4:051.77:250.47:147:32Waning Crescent16Wed
17Thu4:301.612:351.410:011.48:220.57:157:31Waning Crescent17Thu
18Fri4:401.61:551.410:001.39:110.67:157:30New Moon18Fri
19Sat4:371.53:081.510:071.29:530.77:167:29New Moon19Sat
20Sun4:371.44:041.510:211.110:300.97:167:27New Moon20Sun
21Mon4:441.44:561.510:411.011:101.07:167:26New Moon21Mon
22Tue4:501.45:531.511:080.911:591.27:177:25New Moon22Tue
23Wed4:501.46:591.511:420.87:177:24Waxing Crescent23Wed
24Thu4:371.48:051.612:561.312:220.77:187:23Waxing Crescent24Thu
25Fri4:251.49:211.61:471.41:050.77:187:22Waxing Crescent25Fri
26Sat11:161.71:460.67:197:21Waxing Crescent26Sat
27Sun2:300.67:197:20First Quarter27Sun
28Mon12:181.73:220.57:197:19First Quarter28Mon
29Tue1:111.74:290.57:207:17First Quarter29Tue
30Wed2:091.85:350.57:207:16First Quarter30Wed
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (8779770)

Common Questions About Port Isabel, TX Tides

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What time does the tide turn (slack tide) in Port Isabel, TX today?

Slack tide in Port Isabel, TX is approximately 10:00 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 Port Isabel, TX?

Port Isabel, TX is currently in a neap phase. Tonight's moon is 56% 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 minimum.

What datum are Port Isabel, TX 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 Port Isabel, TX?

Tide predictions for Port Isabel, TX 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 Port Isabel, TX?

Tide data for Port Isabel, TX is sourced from NOAA Station #8779770. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=8779770.

What is the moon phase in Port Isabel, TX tonight?

Tonight the moon over Port Isabel, TX is First Quarter (56% illuminated). This places Port Isabel, TX in a neap tide cycle, so tidal ranges are near their weekly minimum 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