Tides Today & Tomorrow in Port Isabel, TX

TIDE TIMES for Monday, August 17, 2026
The tide is currently rising in Port Isabel, TX.
Next low tide (tomorrow) : 2:43 am (1.1 ft)
Next high tide : in 5h 04m at 10:17 pm (1.2 ft)
Sunset today : 8:03 pm
Sunrise tomorrow : 7:02 am
Moon phase : Waxing Crescent (27% illuminated)
Tide Station Location : Station #8779770
Common Questions About Tides

Port Isabel, TX Tides - Mar 2005

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue9:001.012:330.06:516:30Waning Gibbous1Tue
2Wed11:261.21:13-0.26:506:31Third Quarter2Wed
3Thu1:481.42:03-0.46:496:31Third Quarter3Thu
4Fri2:481.53:11-0.46:486:32Third Quarter4Fri
5Sat3:321.54:26-0.56:476:32Waning Crescent5Sat
6Sun4:121.55:35-0.56:466:33Waning Crescent6Sun
7Mon4:431.46:44-0.56:456:33Waning Crescent7Mon
8Tue4:471.27:50-0.49:001.16:446:34New Moon8Tue
9Wed12:051.24:291.08:49-0.29:060.86:436:34New Moon9Wed
10Thu2:151.24:210.99:430.09:330.66:426:35New Moon10Thu
11Fri3:381.24:200.810:430.310:100.36:416:35New Moon11Fri
12Sat5:021.24:170.811:520.610:550.16:406:36Waxing Crescent12Sat
13Sun6:341.23:510.91:030.86:396:36Waxing Crescent13Sun
14Mon8:141.36:386:37Waxing Crescent14Mon
15Tue10:381.312:26-0.16:376:37Waxing Crescent15Tue
16Wed12:011.41:10-0.26:366:38First Quarter16Wed
17Thu1:341.41:59-0.16:356:38First Quarter17Thu
18Fri2:351.43:03-0.16:346:39First Quarter18Fri
19Sat3:171.44:170.06:336:39First Quarter19Sat
20Sun3:491.35:210.06:326:40Waxing Gibbous20Sun
21Mon4:101.36:190.06:316:40Waxing Gibbous21Mon
22Tue4:101.27:150.19:161.06:306:41Waxing Gibbous22Tue
23Wed12:021.03:491.18:030.28:580.96:296:41Waxing Gibbous23Wed
24Thu1:521.13:351.08:460.39:080.76:276:42Full Moon24Thu
25Fri3:001.13:281.09:280.59:270.56:266:42Full Moon25Fri
26Sat4:011.23:180.910:180.79:520.36:256:43Full Moon26Sat
27Sun5:111.32:591.011:290.910:240.16:246:43Waning Gibbous27Sun
28Mon6:271.411:04-0.16:236:43Waning Gibbous28Mon
29Tue7:451.511:51-0.26:226:44Waning Gibbous29Tue
30Wed9:521.56:216:44Waning Gibbous30Wed
31Thu11:271.612:42-0.36:206:45Third Quarter31Thu
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 12:30 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 27% 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 Waxing Crescent (27% 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