Tides Today & Tomorrow in Port Isabel, TX

TIDE TIMES for Friday, August 21, 2026
The tide is currently falling in Port Isabel, TX.
Next low tide : in 4h 38m at 5:20 pm (0.0 ft)
Next high tide (tomorrow) : 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 1996

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun6:071.28:241.41:170.91:030.57:097:48Waning Gibbous1Sun
2Mon6:191.310:531.42:161.11:530.47:097:47Waning Gibbous2Mon
3Tue5:301.33:301.32:420.37:097:46Third Quarter3Tue
4Wed12:331.53:380.37:107:45Third Quarter4Wed
5Thu2:021.64:430.37:107:43Third Quarter5Thu
6Fri3:141.65:440.47:117:42Third Quarter6Fri
7Sat3:551.66:360.47:117:41Waning Crescent7Sat
8Sun4:241.67:260.47:117:40Waning Crescent8Sun
9Mon4:421.512:211.310:171.38:150.57:127:39Waning Crescent9Mon
10Tue4:421.41:371.39:521.38:590.67:127:38Waning Crescent10Tue
11Wed4:341.42:511.49:551.29:380.77:137:37New Moon11Wed
12Thu4:351.43:481.410:121.110:140.87:137:36New Moon12Thu
13Fri4:411.44:391.410:371.010:530.97:137:35New Moon13Fri
14Sat4:481.45:371.511:080.811:391.07:147:34New Moon14Sat
15Sun4:501.46:461.511:460.77:147:32Waxing Crescent15Sun
16Mon4:491.47:581.512:381.212:290.67:157:31Waxing Crescent16Mon
17Tue4:481.49:211.61:361.31:130.57:157:30Waxing Crescent17Tue
18Wed4:461.511:251.72:311.51:580.47:157:29First Quarter18Wed
19Thu2:480.47:167:28First Quarter19Thu
20Fri12:361.73:510.37:167:27First Quarter20Fri
21Sat1:471.85:030.37:177:26First Quarter21Sat
22Sun2:461.86:100.47:177:25Waxing Gibbous22Sun
23Mon3:031.710:43 AM1.58:171.57:140.57:187:24Waxing Gibbous23Mon
24Tue3:111.612:381.68:211.48:200.67:187:22Waxing Gibbous24Tue
25Wed3:231.52:161.68:491.29:220.77:187:21Full Moon25Wed
26Thu3:381.53:381.79:231.010:180.97:197:20Full Moon26Thu
27Fri3:551.54:461.79:590.811:171.17:197:19Full Moon27Fri
28Sat4:111.45:591.810:390.67:207:18Full Moon28Sat
29Sun4:241.57:201.812:311.311:25 AM0.57:207:17Waning Gibbous29Sun
30Mon4:251.58:411.81:451.412:150.57:207:16Waning Gibbous30Mon
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 10:51 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 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