Tides Today & Tomorrow in Port Isabel, TX

TIDE TIMES for Tuesday, July 21, 2026
The tide is currently rising in Port Isabel, TX.
Next low tide (tomorrow) : 5:19 pm (-0.2 ft)
Next high tide (tomorrow) : in 5h 12m at 3:17 am (1.1 ft)
Sunset today : 8:21 pm
Sunrise tomorrow : 6:49 am
Moon phase : First Quarter (53% illuminated)
Tide Station Location : Station #8779770
Common Questions About Tides

Port Isabel, TX Tides - Aug 2073

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue5:581.48:37-0.46:558:15Waning Crescent1Tue
2Wed6:331.49:23-0.46:558:14New Moon2Wed
3Thu6:581.410:08-0.36:568:13New Moon3Thu
4Fri7:091.310:55-0.26:568:13New Moon4Fri
5Sat7:181.33:471.112:581.06:578:12Waxing Crescent5Sat
6Sun7:291.25:151.01:230.96:578:11Waxing Crescent6Sun
7Mon7:421.17:091.012:440.21:560.76:588:10Waxing Crescent7Mon
8Tue7:541.19:001.01:390.42:360.46:588:10First Quarter8Tue
9Wed8:011.111:231.12:330.73:250.26:598:09First Quarter9Wed
10Thu7:551.13:451.04:240.16:598:08First Quarter10Thu
11Fri1:301.35:23-0.17:008:07First Quarter11Fri
12Sat3:281.46:18-0.27:008:07Waxing Gibbous12Sat
13Sun4:171.57:11-0.27:018:06Waxing Gibbous13Sun
14Mon4:591.58:05-0.27:018:05Waxing Gibbous14Mon
15Tue5:391.58:56-0.17:028:04Waxing Gibbous15Tue
16Wed6:131.49:390.07:028:03Full Moon16Wed
17Thu6:311.310:190.17:028:02Full Moon17Thu
18Fri6:321.33:111.211:371.110:570.27:038:01Full Moon18Fri
19Sat6:361.24:121.112:001.07:038:00Full Moon19Sat
20Sun6:491.25:121.112:330.97:047:59Waning Gibbous20Sun
21Mon7:031.26:371.112:220.61:060.87:047:58Waning Gibbous21Mon
22Tue7:151.18:061.11:060.71:400.77:057:58Waning Gibbous22Tue
23Wed7:161.110:081.11:460.92:160.57:057:57Waning Gibbous23Wed
24Thu6:471.22:231.12:560.47:067:56Third Quarter24Thu
25Fri12:371.26:00 AM1.23:151.23:460.37:067:55Third Quarter25Fri
26Sat3:121.34:440.37:067:54Third Quarter26Sat
27Sun3:451.55:380.27:077:53Third Quarter27Sun
28Mon4:131.56:290.17:077:52Waning Crescent28Mon
29Tue4:381.67:210.17:087:51Waning Crescent29Tue
30Wed4:581.68:150.07:087:49Waning Crescent30Wed
31Thu5:091.69:080.17:087:48New Moon31Thu
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (8779770)

Common Questions About Port Isabel, TX Tides

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

Slack tide in Port Isabel, TX is approximately 10:18 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 neap phase. Tonight's moon is 53% 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 (53% 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