Tides Today & Tomorrow in Port Isabel, TX

TIDE TIMES for Thursday, August 20, 2026
The tide is currently falling in Port Isabel, TX.
Next low tide : in 10h 15m at 4:19 pm (0.1 ft)
Next high tide (tomorrow) : 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 - Jul 1999

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Thu8:331.311:53-0.36:408:25Waning Gibbous1Thu
2Fri8:551.26:408:25Waning Gibbous2Fri
3Sat9:171.212:37-0.26:418:25Waning Gibbous3Sat
4Sun9:381.11:21-0.16:418:25Third Quarter4Sun
5Mon9:551.08:520.62:020.14:440.56:418:24Third Quarter5Mon
6Tue10:091.011:480.72:440.45:110.36:428:24Third Quarter6Tue
7Wed10:140.94:000.65:450.06:428:24Third Quarter7Wed
8Thu2:030.910:05 AM0.96:150.96:24-0.26:438:24Waning Crescent8Thu
9Fri4:031.17:08-0.56:438:24Waning Crescent9Fri
10Sat4:521.37:57-0.66:438:24Waning Crescent10Sat
11Sun5:471.48:49-0.76:448:24New Moon11Sun
12Mon6:451.49:39-0.76:448:24New Moon12Mon
13Tue7:321.410:28-0.66:458:23New Moon13Tue
14Wed8:071.411:18-0.56:458:23New Moon14Wed
15Thu8:311.36:468:23Waxing Crescent15Thu
16Fri8:461.112:11-0.36:468:23Waxing Crescent16Fri
17Sat8:571.06:460.71:03-0.13:140.76:478:22Waxing Crescent17Sat
18Sun9:101.08:470.71:480.23:540.56:478:22First Quarter18Sun
19Mon9:230.911:150.72:280.44:390.46:488:22First Quarter19Mon
20Tue9:300.93:060.65:180.26:488:21First Quarter20Tue
21Wed1:420.98:42 AM0.94:460.85:530.16:498:21First Quarter21Wed
22Thu3:561.06:28-0.16:498:20Waxing Gibbous22Thu
23Fri4:321.17:05-0.26:508:20Waxing Gibbous23Fri
24Sat5:081.27:45-0.26:508:20Waxing Gibbous24Sat
25Sun5:461.38:26-0.36:518:19Waxing Gibbous25Sun
26Mon6:251.39:06-0.36:518:19Full Moon26Mon
27Tue6:571.39:44-0.36:528:18Full Moon27Tue
28Wed7:171.310:21-0.36:528:18Full Moon28Wed
29Thu7:291.310:59-0.26:538:17Full Moon29Thu
30Fri7:401.211:42-0.16:538:16Waning Gibbous30Fri
31Sat7:531.24:070.91:530.96:548:16Waning Gibbous31Sat
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 10:00 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 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