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 14m at 2:43 am (1.1 ft)
Next high tide : 4:52 am (1.1 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 - May 2004

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat1:051.02:011.17:360.58:210.66:518:00Waxing Gibbous1Sat
2Sun2:491.21:501.08:560.78:420.36:508:01Waxing Gibbous2Sun
3Mon4:041.41:221.010:130.99:120.06:498:01Full Moon3Mon
4Tue5:121.69:48-0.26:488:02Full Moon4Tue
5Wed6:281.710:30-0.46:488:02Full Moon5Wed
6Thu7:471.811:19-0.56:478:03Waning Gibbous6Thu
7Fri9:071.86:468:03Waning Gibbous7Fri
8Sat10:441.812:18-0.66:468:04Waning Gibbous8Sat
9Sun11:501.71:19-0.56:458:04Waning Gibbous9Sun
10Mon12:361.62:19-0.36:448:05Third Quarter10Mon
11Tue1:081.43:23-0.16:448:06Third Quarter11Tue
12Wed1:171.34:430.16:438:06Third Quarter12Wed
13Thu1:121.16:020.47:520.76:438:07Waning Crescent13Thu
14Fri12:561.01:081.07:220.68:000.56:428:07Waning Crescent14Fri
15Sat3:131.11:041.09:030.88:210.26:428:08Waning Crescent15Sat
16Sun4:331.38:460.16:418:08Waning Crescent16Sun
17Mon5:371.49:12-0.16:418:09New Moon17Mon
18Tue6:401.59:40-0.26:408:09New Moon18Tue
19Wed7:321.510:10-0.36:408:10New Moon19Wed
20Thu8:171.610:44-0.36:398:10New Moon20Thu
21Fri9:071.511:24-0.36:398:11Waxing Crescent21Fri
22Sat10:131.56:398:11Waxing Crescent22Sat
23Sun11:091.512:10-0.36:388:12Waxing Crescent23Sun
24Mon11:441.512:58-0.26:388:12Waxing Crescent24Mon
25Tue12:051.41:43-0.16:388:13First Quarter25Tue
26Wed12:111.32:260.06:378:13First Quarter26Wed
27Thu12:101.23:150.16:378:14First Quarter27Thu
28Fri12:081.14:240.37:000.66:378:14First Quarter28Fri
29Sat12:120.812:021.05:470.67:040.36:378:15Waxing Gibbous29Sat
30Sun2:021.011:45 AM1.07:150.87:260.06:368:15Waxing Gibbous30Sun
31Mon3:381.38:00-0.36:368:16Waxing Gibbous31Mon
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 3:47 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 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