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 1h 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 - Apr 2003

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue3:181.23:251.09:530.69:210.56:196:45New Moon1Tue
2Wed4:151.23:220.910:470.89:450.36:186:46New Moon2Wed
3Thu5:201.33:031.012:010.96:176:46New Moon3Thu
4Fri6:261.310:500.16:166:46Waxing Crescent4Fri
5Sat7:321.411:320.06:156:47Waxing Crescent5Sat
6Sun10:191.47:147:47Waxing Crescent6Sun
7Mon11:561.41:150.07:137:48Waxing Crescent7Mon
8Tue1:001.52:000.07:127:48First Quarter8Tue
9Wed2:191.52:510.07:117:49First Quarter9Wed
10Thu3:131.53:550.07:107:49First Quarter10Thu
11Fri3:411.55:090.07:097:50First Quarter11Fri
12Sat3:471.46:160.17:087:50Waxing Gibbous12Sat
13Sun3:351.37:220.28:591.07:077:51Waxing Gibbous13Sun
14Mon1:071.23:281.18:330.39:030.87:067:51Waxing Gibbous14Mon
15Tue2:581.33:251.09:390.59:260.57:057:52Full Moon15Tue
16Wed4:171.43:201.010:460.79:580.27:047:52Full Moon16Wed
17Thu5:321.63:031.012:191.07:037:53Full Moon17Thu
18Fri6:561.711:25-0.37:027:53Waning Gibbous18Fri
19Sat8:191.87:017:54Waning Gibbous19Sat
20Sun10:001.812:21-0.47:007:54Waning Gibbous20Sun
21Mon11:361.81:19-0.47:007:55Waning Gibbous21Mon
22Tue12:411.72:16-0.36:597:55Third Quarter22Tue
23Wed1:431.63:18-0.16:587:56Third Quarter23Wed
24Thu2:351.54:370.16:577:56Third Quarter24Thu
25Fri3:001.35:550.26:567:57Waning Crescent25Fri
26Sat2:561.27:040.49:080.96:557:57Waning Crescent26Sat
27Sun1:201.02:431.18:180.68:560.76:547:58Waning Crescent27Sun
28Mon3:051.12:391.09:250.79:040.56:547:58Waning Crescent28Mon
29Tue4:141.22:361.010:230.99:220.36:537:59New Moon29Tue
30Wed5:101.39:430.26:527:59New Moon30Wed
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