Tides Today & Tomorrow in Port Isabel, TX

TIDE TIMES for Tuesday, August 18, 2026
The tide is currently falling in Port Isabel, TX.
Next low tide : in 9h 20m at 2:34 pm (0.2 ft)
Next high tide (tomorrow) : 12:36 am (1.4 ft)
Sunset today : 8:02 pm
Sunrise tomorrow : 7:03 am
Moon phase : First Quarter (37% illuminated)
Tide Station Location : Station #8779770
Common Questions About Tides

Port Isabel, TX Tides - Feb 2004

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun4:191.25:35-0.47:136:11Waxing Gibbous1Sun
2Mon5:031.26:24-0.57:126:12Waxing Gibbous2Mon
3Tue5:461.27:14-0.67:126:13Waxing Gibbous3Tue
4Wed6:221.28:01-0.67:116:13Full Moon4Wed
5Thu6:461.18:42-0.67:106:14Full Moon5Thu
6Fri6:551.19:21-0.57:106:15Full Moon6Fri
7Sat6:451.010:00-0.47:096:16Full Moon7Sat
8Sun2:250.86:360.912:130.810:43 AM-0.37:096:16Waning Gibbous8Sun
9Mon3:510.86:310.812:150.611:31 AM-0.17:086:17Waning Gibbous9Mon
10Tue5:410.76:210.712:340.412:200.27:076:18Waning Gibbous10Tue
11Wed7:350.85:560.71:010.21:090.57:076:18Waning Gibbous11Wed
12Thu10:100.95:060.81:37-0.12:130.87:066:19Third Quarter12Thu
13Fri1:091.12:26-0.37:056:20Third Quarter13Fri
14Sat2:411.33:28-0.57:056:20Third Quarter14Sat
15Sun3:291.44:34-0.67:046:21Waning Crescent15Sun
16Mon4:151.45:37-0.77:036:22Waning Crescent16Mon
17Tue5:041.46:41-0.77:026:22Waning Crescent17Tue
18Wed5:451.37:45-0.77:026:23New Moon18Wed
19Thu6:061.18:40-0.67:016:24New Moon19Thu
20Fri5:591.09:30-0.410:130.87:006:24New Moon20Fri
21Sat2:291.05:450.910:19-0.210:410.66:596:25New Moon21Sat
22Sun3:460.95:430.811:110.111:190.46:586:26Waxing Crescent22Sun
23Mon5:100.95:430.712:040.36:576:26Waxing Crescent23Mon
24Tue6:420.95:310.712:530.66:576:27Waxing Crescent24Tue
25Wed8:310.94:020.812:340.11:480.86:566:27Waxing Crescent25Wed
26Thu11:221.01:110.06:556:28First Quarter26Thu
27Fri1:251.11:53-0.16:546:28First Quarter27Fri
28Sat2:321.22:46-0.26:536:29First Quarter28Sat
29Sun3:131.33:52-0.26:526:30First Quarter29Sun
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 7:35 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 37% 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 (37% 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