Tides Today & Tomorrow in Port Isabel, TX

TIDE TIMES for Friday, August 21, 2026
The tide is currently rising in Port Isabel, TX.
Next low tide (tomorrow) : 6:15 pm (0.0 ft)
Next high tide (tomorrow) : in 6h 36m at 4:23 am (1.6 ft)
Sunset today : 7:59 pm
Sunrise tomorrow : 7:04 am
Moon phase : First Quarter (65% illuminated)
Tide Station Location : Station #8779770
Common Questions About Tides

Port Isabel, TX Tides - Sep 1995

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri5:301.43:011.43:010.27:087:48First Quarter1Fri
2Sat12:561.54:050.17:097:47First Quarter2Sat
3Sun2:541.65:140.17:097:46First Quarter3Sun
4Mon3:411.76:170.17:107:45Waxing Gibbous4Mon
5Tue4:071.67:190.17:107:44Waxing Gibbous5Tue
6Wed4:181.611:51 AM1.59:021.48:210.27:107:43Waxing Gibbous6Wed
7Thu4:191.51:301.59:131.39:180.47:117:42Full Moon7Thu
8Fri4:231.43:031.59:391.110:090.67:117:41Full Moon8Fri
9Sat4:341.34:141.510:110.910:590.87:127:40Full Moon9Sat
10Sun4:481.35:211.510:470.811:561.07:127:39Full Moon10Sun
11Mon5:031.36:381.511:290.77:127:38Waning Gibbous11Mon
12Tue5:121.37:581.51:001.112:160.67:137:37Waning Gibbous12Tue
13Wed5:021.39:461.51:571.31:030.57:137:35Waning Gibbous13Wed
14Thu11:591.61:480.57:147:34Waning Gibbous14Thu
15Fri2:330.57:147:33Third Quarter15Fri
16Sat1:081.63:260.57:147:32Third Quarter16Sat
17Sun2:311.64:300.57:157:31Third Quarter17Sun
18Mon3:211.65:330.57:157:30Third Quarter18Mon
19Tue3:471.66:260.67:167:29Waning Crescent19Tue
20Wed3:581.67:180.67:167:28Waning Crescent20Wed
21Thu3:501.512:471.49:061.38:100.77:167:27Waning Crescent21Thu
22Fri3:431.52:111.59:121.29:000.87:177:25Waning Crescent22Fri
23Sat3:461.53:221.59:311.19:460.97:177:24New Moon23Sat
24Sun3:531.44:211.69:570.910:321.07:187:23New Moon24Sun
25Mon4:001.45:211.710:270.811:261.27:187:22New Moon25Mon
26Tue4:031.46:331.711:040.67:187:21Waxing Crescent26Tue
27Wed4:041.57:491.812:381.411:50 AM0.57:197:20Waxing Crescent27Wed
28Thu4:041.59:151.81:461.512:430.47:197:19Waxing Crescent28Thu
29Fri11:201.81:370.37:207:18Waxing Crescent29Fri
30Sat2:320.37:207:17First Quarter30Sat
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 11:19 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 Port Isabel, TX?

Port Isabel, TX is currently in a transitional phase. Tonight's moon is 65% 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 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 (65% illuminated). This places Port Isabel, TX 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