Tides Today & Tomorrow in Port Isabel, TX

TIDE TIMES for Thursday, August 20, 2026
The tide is currently rising in Port Isabel, TX.
Next low tide (tomorrow) : 5:20 pm (0.0 ft)
Next high tide (tomorrow) : in 10h 09m at 3:41 am (1.6 ft)
Sunset today : 8:00 pm
Sunrise tomorrow : 7:03 am
Moon phase : First Quarter (56% illuminated)
Tide Station Location : Station #8779770
Common Questions About Tides

Port Isabel, TX Tides - Apr 1998

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed8:581.412:10-0.16:196:45Waxing Crescent1Wed
2Thu10:481.41:02-0.16:186:46First Quarter2Thu
3Fri11:591.41:570.06:176:46First Quarter3Fri
4Sat1:111.43:040.16:166:47First Quarter4Sat
5Sun3:051.35:200.27:157:47First Quarter5Sun
6Mon3:331.26:260.39:380.97:147:48Waxing Gibbous6Mon
7Tue12:221.03:411.27:300.49:320.87:137:48Waxing Gibbous7Tue
8Wed1:431.03:361.18:320.59:320.77:127:48Waxing Gibbous8Wed
9Thu2:591.13:361.09:230.69:410.67:117:49Waxing Gibbous9Thu
10Fri3:551.23:411.010:040.79:570.57:107:49Full Moon10Fri
11Sat4:421.23:451.010:440.810:190.47:097:50Full Moon11Sat
12Sun5:311.33:421.011:330.910:450.37:087:50Full Moon12Sun
13Mon6:261.33:301.012:381.07:077:51Full Moon13Mon
14Tue7:211.311:530.27:067:51Waning Gibbous14Tue
15Wed8:151.47:057:52Waning Gibbous15Wed
16Thu9:181.412:350.17:047:52Waning Gibbous16Thu
17Fri10:431.41:190.17:037:53Waning Gibbous17Fri
18Sat11:431.42:030.17:027:53Third Quarter18Sat
19Sun12:241.42:530.17:017:54Third Quarter19Sun
20Mon12:591.44:010.27:007:54Third Quarter20Mon
21Tue1:281.35:210.27:591.06:597:55Waning Crescent21Tue
22Wed1:531.26:320.37:540.96:587:55Waning Crescent22Wed
23Thu12:481.12:151.27:470.58:190.66:587:56Waning Crescent23Thu
24Fri2:291.22:351.19:030.68:530.46:577:56Waning Crescent24Fri
25Sat3:491.42:521.110:110.89:300.16:567:57New Moon25Sat
26Sun4:561.53:041.111:230.910:100.06:557:57New Moon26Sun
27Mon6:091.63:091.11:061.16:547:58New Moon27Mon
28Tue7:251.611:46-0.26:537:58Waxing Crescent28Tue
29Wed8:381.66:537:59Waxing Crescent29Wed
30Thu10:061.612:40-0.26:527:59Waxing Crescent30Thu
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 10:30 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 neap phase. Tonight's moon is 56% 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 near their weekly minimum.

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 (56% illuminated). This places Port Isabel, TX in a neap tide cycle, so tidal ranges are near their weekly minimum 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