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 11h 47m 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 1999

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed6:401.311:321.42:371.12:300.37:087:48Third Quarter1Wed
2Thu3:240.27:097:47Third Quarter2Thu
3Fri1:251.64:290.17:097:46Third Quarter3Fri
4Sat3:061.75:340.17:107:45Waning Crescent4Sat
5Sun3:561.76:350.07:107:44Waning Crescent5Sun
6Mon4:331.77:350.17:107:43Waning Crescent6Mon
7Tue5:021.78:340.27:117:42Waning Crescent7Tue
8Wed5:171.61:351.410:131.49:270.37:117:41New Moon8Wed
9Thu5:171.53:051.510:251.210:140.57:127:40New Moon9Thu
10Fri5:201.44:111.510:481.110:590.77:127:39New Moon10Fri
11Sat5:291.35:141.511:191.011:490.87:127:38New Moon11Sat
12Sun5:391.36:271.511:570.87:137:37Waxing Crescent12Sun
13Mon5:431.37:431.512:461.012:380.77:137:35Waxing Crescent13Mon
14Tue5:231.39:031.51:391.21:170.67:147:34Waxing Crescent14Tue
15Wed4:411.411:141.52:291.31:560.67:147:33Waxing Crescent15Wed
16Thu2:390.57:147:32First Quarter16Thu
17Fri12:321.63:310.57:157:31First Quarter17Fri
18Sat1:581.64:360.57:157:30First Quarter18Sat
19Sun3:081.75:370.57:167:29First Quarter19Sun
20Mon3:391.76:310.57:167:28Waxing Gibbous20Mon
21Tue3:551.77:240.57:167:27Waxing Gibbous21Tue
22Wed4:021.78:180.57:177:25Waxing Gibbous22Wed
23Thu4:091.61:131.59:271.49:090.67:177:24Full Moon23Thu
24Fri4:201.62:531.59:441.29:570.77:187:23Full Moon24Fri
25Sat4:321.54:031.610:091.110:480.97:187:22Full Moon25Sat
26Sun4:431.55:111.710:400.911:501.17:187:21Full Moon26Sun
27Mon4:511.46:321.711:200.77:197:20Waning Gibbous27Mon
28Tue4:511.47:581.81:051.312:090.57:197:19Waning Gibbous28Tue
29Wed4:371.59:441.82:171.41:030.47:207:18Waning Gibbous29Wed
30Thu11:501.91:550.37:207:17Third Quarter30Thu
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