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 36m 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 - Mar 2003

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat5:331.18:29-0.36:526:30New Moon1Sat
2Sun5:241.09:12-0.29:580.86:516:30New Moon2Sun
3Mon2:201.05:100.99:530.010:110.76:506:31New Moon3Mon
4Tue3:240.95:090.810:350.210:360.56:496:31New Moon4Tue
5Wed4:280.95:100.811:220.411:090.46:486:32Waxing Crescent5Wed
6Thu5:460.94:590.812:110.66:476:32Waxing Crescent6Thu
7Fri7:051.04:130.812:590.86:466:33Waxing Crescent7Fri
8Sat8:521.012:220.16:456:34Waxing Crescent8Sat
9Sun11:271.11:000.06:446:34First Quarter9Sun
10Mon1:281.21:43-0.16:436:35First Quarter10Mon
11Tue2:281.32:38-0.16:426:35First Quarter11Tue
12Wed3:071.43:46-0.26:416:36First Quarter12Wed
13Thu3:401.44:51-0.26:406:36Waxing Gibbous13Thu
14Fri4:091.45:50-0.36:396:37Waxing Gibbous14Fri
15Sat4:261.36:50-0.36:386:37Waxing Gibbous15Sat
16Sun4:221.27:49-0.29:091.06:376:38Waxing Gibbous16Sun
17Mon12:351.14:131.18:44-0.19:150.86:356:38Full Moon17Mon
18Tue2:281.24:101.09:370.19:370.66:346:39Full Moon18Tue
19Wed3:461.34:080.910:380.410:130.36:336:39Full Moon19Wed
20Thu5:111.33:580.911:510.710:590.16:326:39Waning Gibbous20Thu
21Fri6:421.43:311.01:060.96:316:40Waning Gibbous21Fri
22Sat8:221.46:306:40Waning Gibbous22Sat
23Sun10:371.512:44-0.36:296:41Third Quarter23Sun
24Mon12:091.61:39-0.36:286:41Third Quarter24Mon
25Tue1:431.62:45-0.36:276:42Third Quarter25Tue
26Wed2:401.54:04-0.26:266:42Third Quarter26Wed
27Thu3:171.45:17-0.16:256:43Waning Crescent27Thu
28Fri3:411.36:250.06:246:43Waning Crescent28Fri
29Sat3:451.27:310.19:041.06:236:44Waning Crescent29Sat
30Sun12:461.13:331.18:250.38:550.86:226:44Waning Crescent30Sun
31Mon2:161.13:261.09:100.49:030.76:216:45New Moon31Mon
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