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 3h 28m 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 - Jul 2003

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue9:121.411:21-0.56:408:25Waxing Crescent1Tue
2Wed9:491.46:408:25Waxing Crescent2Wed
3Thu10:101.312:08-0.46:418:25Waxing Crescent3Thu
4Fri10:091.212:56-0.36:418:25Waxing Crescent4Fri
5Sat10:041.11:41-0.16:418:24First Quarter5Sat
6Sun10:001.010:350.72:260.24:580.46:428:24First Quarter6Sun
7Mon9:480.93:200.55:210.16:428:24First Quarter7Mon
8Tue12:450.99:11 AM0.95:200.85:54-0.26:438:24First Quarter8Tue
9Wed3:321.16:35-0.56:438:24Waxing Gibbous9Wed
10Thu4:331.47:22-0.76:438:24Waxing Gibbous10Thu
11Fri5:301.58:14-0.86:448:24Waxing Gibbous11Fri
12Sat6:341.69:07-0.86:448:24Full Moon12Sat
13Sun7:301.69:57-0.86:458:23Full Moon13Sun
14Mon8:151.510:47-0.76:458:23Full Moon14Mon
15Tue8:521.411:39-0.56:468:23Waning Gibbous15Tue
16Wed9:171.36:468:23Waning Gibbous16Wed
17Thu9:191.112:31-0.36:478:22Waning Gibbous17Thu
18Fri9:151.05:370.71:190.03:120.76:478:22Waning Gibbous18Fri
19Sat9:170.99:030.72:000.23:390.56:488:22Third Quarter19Sat
20Sun9:180.92:370.54:160.36:488:21Third Quarter20Sun
21Mon12:150.88:56 AM0.93:150.84:550.16:498:21Third Quarter21Mon
22Tue3:371.05:320.06:498:20Third Quarter22Tue
23Wed4:121.26:10-0.26:508:20Waning Crescent23Wed
24Thu4:491.36:50-0.36:508:20Waning Crescent24Thu
25Fri5:301.47:33-0.46:518:19Waning Crescent25Fri
26Sat6:161.48:19-0.46:518:19Waning Crescent26Sat
27Sun7:021.59:04-0.56:528:18New Moon27Sun
28Mon7:401.59:46-0.56:528:18New Moon28Mon
29Tue8:101.410:27-0.46:538:17New Moon29Tue
30Wed8:291.411:10-0.36:538:16New Moon30Wed
31Thu8:301.36:548:16Waxing Crescent31Thu
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