Tides Today & Tomorrow in Port Isabel, TX

TIDE TIMES for Tuesday, August 18, 2026
The tide is currently rising in Port Isabel, TX.
Next low tide (tomorrow) : 3:20 pm (0.1 ft)
Next high tide (tomorrow) : in 3h 52m at 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 - Jan 2003

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed5:461.57:44-0.87:165:48New Moon1Wed
2Thu6:391.58:33-0.87:165:49New Moon2Thu
3Fri7:251.49:20-0.87:165:50New Moon3Fri
4Sat8:061.310:07-0.77:165:50Waxing Crescent4Sat
5Sun8:381.210:57-0.57:175:51Waxing Crescent5Sun
6Mon8:481.011:45-0.37:175:52Waxing Crescent6Mon
7Tue8:450.912:28-0.17:175:52Waxing Crescent7Tue
8Wed8:470.81:040.17:175:53First Quarter8Wed
9Thu7:350.58:490.73:120.51:350.37:175:54First Quarter9Thu
10Fri11:070.68:260.73:440.31:400.67:175:55First Quarter10Fri
11Sat3:010.84:180.17:175:55First Quarter11Sat
12Sun3:251.04:52-0.17:175:56Waxing Gibbous12Sun
13Mon3:581.15:29-0.37:175:57Waxing Gibbous13Mon
14Tue4:361.26:09-0.47:175:58Waxing Gibbous14Tue
15Wed5:211.36:53-0.67:175:58Waxing Gibbous15Wed
16Thu6:051.37:38-0.77:175:59Full Moon16Thu
17Fri6:441.38:22-0.77:176:00Full Moon17Fri
18Sat7:181.39:05-0.87:176:01Full Moon18Sat
19Sun7:431.29:48-0.77:176:02Full Moon19Sun
20Mon7:511.110:35-0.67:166:02Waning Gibbous20Mon
21Tue7:471.011:26-0.57:166:03Waning Gibbous21Tue
22Wed3:460.87:440.81:240.712:16-0.27:166:04Waning Gibbous22Wed
23Thu6:140.77:400.71:420.51:050.17:166:05Third Quarter23Thu
24Fri8:420.77:220.72:160.21:560.47:166:05Third Quarter24Fri
25Sat11:210.86:310.83:04-0.14:030.87:156:06Third Quarter25Sat
26Sun2:241.14:00-0.37:156:07Third Quarter26Sun
27Mon3:191.24:53-0.67:156:08Waning Crescent27Mon
28Tue4:071.35:46-0.77:146:08Waning Crescent28Tue
29Wed4:591.46:43-0.87:146:09Waning Crescent29Wed
30Thu5:501.37:39-0.87:136:10New Moon30Thu
31Fri6:301.28:30-0.77:136:11New Moon31Fri
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 7:58 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 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