Coastal Waters Forecast for Waters from Port Mansfield TX to the Rio Grande River from 20 to 60 NM (GMZ170) (Text-Only)
NWS Forecast for: Waters from Port Mansfield TX to the Rio Grande River from 20 to 60 NM (GMZ170)
Issued by: National Weather Service Brownsville, TX
Last Update: 223 AM CDT Sun Sep 20 2026


Today: Southeast winds 5 to 10 knots, becoming east this afternoon. Seas 3 to 4 feet. Wave detail: east 3 feet at 7 seconds. A chance of showers with a slight chance of thunderstorms this morning, then a slight chance of showers and thunderstorms early this afternoon.

Tonight: Southeast winds around 10 knots, becoming 5 to 10 knots early in the morning. Seas 2 to 4 feet. Wave detail: east 3 feet at 6 seconds.

Monday: Southeast winds 5 to 10 knots, becoming east in the afternoon. Seas 2 to 3 feet. Wave detail: east 2 feet at 6 seconds. A slight chance of showers and thunderstorms in the afternoon.

Monday Night: East winds 10 to 15 knots, becoming southeast 5 to 10 knots early in the morning. Seas 2 to 3 feet. Wave detail: east 2 feet at 5 seconds.

Tuesday: East winds 5 to 10 knots, increasing to 10 to 15 knots in the afternoon. Seas 2 to 3 feet. Wave detail: east 2 feet at 5 seconds and east 1 foot at 8 seconds. A chance of showers. A slight chance of thunderstorms in the morning, then a chance of thunderstorms in the afternoon.

Tuesday Night: East winds 10 to 15 knots. Seas 2 to 3 feet. Wave detail: east 3 feet at 4 seconds and east 1 foot at 9 seconds. A slight chance of thunderstorms. A chance of showers early in the evening, then a slight chance of showers in the late evening and overnight.

Wednesday: East winds 10 to 15 knots. Seas 2 to 3 feet. A chance of showers. A slight chance of thunderstorms in the morning, then a chance of thunderstorms in the afternoon.

Wednesday Night: East winds 10 to 15 knots. Seas 3 to 4 feet. A chance of thunderstorms in the evening. A chance of showers. A slight chance of thunderstorms after midnight.

Thursday: East winds 10 to 15 knots. Seas 3 to 4 feet. A chance of showers and thunderstorms.

Thursday Night: East winds 10 to 15 knots. Seas 3 to 4 feet. A chance of showers and thunderstorms.

winds and seas higher in and near thunderstorms.







Zone Forecast: Waters from Port Mansfield TX to the Rio Grande River from 20 to 60 NM (GMZ170)

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