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 4h 18m 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 - Aug 2003

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri8:221.24:271.02:140.96:548:15Waxing Crescent1Fri
2Sat8:181.16:540.912:500.12:260.76:558:15Waxing Crescent2Sat
3Sun8:131.09:140.91:410.42:530.46:558:14First Quarter3Sun
4Mon7:571.011:521.12:320.73:330.26:568:13First Quarter4Mon
5Tue7:191.13:591.04:25-0.16:568:13First Quarter5Tue
6Wed2:441.35:20-0.36:578:12First Quarter6Wed
7Thu3:561.56:13-0.46:578:11Waxing Gibbous7Thu
8Fri4:451.67:09-0.56:588:10Waxing Gibbous8Fri
9Sat5:371.78:08-0.56:588:10Waxing Gibbous9Sat
10Sun6:321.69:04-0.56:598:09Full Moon10Sun
11Mon7:171.69:54-0.36:598:08Full Moon11Mon
12Tue7:451.410:40-0.27:008:07Full Moon12Tue
13Wed7:491.311:270.07:008:06Full Moon13Wed
14Thu7:361.24:191.112:441.07:008:06Waning Gibbous14Thu
15Fri7:311.15:491.112:160.31:100.97:018:05Waning Gibbous15Fri
16Sat7:331.17:411.01:050.51:390.77:018:04Waning Gibbous16Sat
17Sun7:321.09:491.11:490.72:110.57:028:03Waning Gibbous17Sun
18Mon6:531.12:341.02:470.47:028:02Third Quarter18Mon
19Tue12:411.23:310.27:038:01Third Quarter19Tue
20Wed2:561.44:260.17:038:00Third Quarter20Wed
21Thu3:441.55:210.17:047:59Third Quarter21Thu
22Fri4:221.66:120.07:047:58Waning Crescent22Fri
23Sat5:001.67:03-0.17:057:57Waning Crescent23Sat
24Sun5:401.67:55-0.17:057:57Waning Crescent24Sun
25Mon6:201.68:45-0.17:057:56Waning Crescent25Mon
26Tue6:491.69:32-0.17:067:55New Moon26Tue
27Wed6:551.510:160.17:067:54New Moon27Wed
28Thu6:391.43:191.311:301.211:030.37:077:53New Moon28Thu
29Fri6:311.34:471.311:551.011:590.57:077:52Waxing Crescent29Fri
30Sat6:281.26:281.312:310.87:087:51Waxing Crescent30Sat
31Sun6:191.28:141.41:040.81:120.57:087:49Waxing Crescent31Sun
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