Port Mansfield, TX to the Rio Grande River Marine Forecast
| Tonight...Northeast Winds 10 To 15 Knots. Seas 3 To 4 Feet. Wave Detail: Northeast 4 Feet At 6 Seconds. A Chance Of Showers With A Slight Chance Of Thunderstorms. |
| Thursday...Northeast Winds Around 15 Knots. Seas 4 To 5 Feet. Wave Detail: Northeast 5 Feet At 6 Seconds. A Slight Chance Of Thunderstorms. A Chance Of Showers Until Late Afternoon, Then A Slight Chance Of Showers Late In The Afternoon. |
| Thursday Night...Northeast Winds 15 To 20 Knots. Seas 5 To 7 Feet, Occasionally To 9 Feet. Wave Detail: Northeast 6 Feet At 8 Seconds. A Slight Chance Of Showers Until Early Morning, Then A Chance Of Showers Early In The Morning. |
| Friday...Northeast Winds 15 To 20 Knots. Seas 6 To 8 Feet, Occasionally To 10 Feet. Wave Detail: Northeast 7 Feet At 8 Seconds And North 3 Feet At 5 Seconds. A Chance Of Showers With A Slight Chance Of Thunderstorms. |
| Friday Night...Northeast Winds 10 To 15 Knots. Seas 6 To 8 Feet, Occasionally To 10 Feet. Wave Detail: Northeast 7 Feet At 9 Seconds And North 3 Feet At 5 Seconds. A Chance Of Showers Early In The Evening. A Slight Chance Of Showers After Midnight. |
| Saturday...North Winds 10 To 15 Knots, Diminishing To 5 To 10 Knots In The Afternoon. Seas 6 To 8 Feet, Occasionally To 10 Feet. Wave Detail: East 8 Feet At 10 Seconds. A Slight Chance Of Showers Early In The Morning. |
| Saturday Night...Northeast Winds 5 To 10 Knots, Becoming Southeast Early In The Morning. Seas 4 To 6 Feet, Occasionally To 8 Feet, Subsiding To 3 To 4 Feet After Midnight. |
| Sunday...Southeast Winds 5 To 10 Knots. Seas 3 To 4 Feet. |
| Sunday Night...Southeast Winds Around 10 Knots. Seas 2 To 4 Feet. A Slight Chance Of Showers. |
| Monday...Southeast Winds Around 10 Knots. Seas 2 To 3 Feet. A Slight Chance Of Showers Until Late Afternoon. A Slight Chance Of Thunderstorms Late In The Morning. |
| Monday Night...Southeast Winds Around 10 Knots. Seas 2 To 3 Feet. Winds And Seas Higher In And Near Thunderstorms. |
| Area Forecast Discussion National Weather Service Brownsville TX 145pm CDT Wednesday Oct 7 2026 Issued at 145pm CDT Wednesday Oct 7 2026 Unsettled weather will continue across the Lower Rio Grande Valley and immediate coast through the end of the week as the region remains beneath persistent northeasterly flow. Additional rounds of light to moderate showers, and perhaps an isolated thunderstorm or two, will continue through at least tomorrow. High res guidance continues to highlight a low probability of isolated amounts upwards of 2-3 inches where heavier showers train across portions of Cameron, Willacy, and Kenedy counties. Given antecedent conditions, locally heavy rainfall may result in minor flooding issues, primarily across low-lying and poor drainage areas. Meanwhile, weak mid level ridging will promote general rain-free and warm conditions across the rest of Deep South Texas. Precipitation chances should begin to taper off by Friday, with most activity remaining mostly over the Gulf waters, and southern Cameron County. Generally rain-free conditions and seasonably warm temperatures in the low to mid 90s are expected this weekend and into next week. An isolated sea breeze shower or thunderstorm cannot be ruled out early next week, but chances are fairly low (10% or less). Tropical Storm Isaias will continue to strengthen and track towards the northern Gulf coast late this week and into the weekend, and while no direct impacts are expected across Deep South Texas, hazardous beach/marine conditions are likely. Coastal flooding and a moderate to high risk of rip currents is the primary concern as seas increase upwards of 5-7 feet late this week and weekend. Persistent northeasterly flow and increasing swell will likely result in waters to push into the dunes, especially along narrow beaches. Marine Issued at 145pm CDT Wednesday Oct 7 2026 Adverse to hazardous marine conditions will likely continue into the weekend. Expect persistent northeasterly winds around 15 to 20 knots with occasionally higher gusts, which will result in elevated seas around 5-7 feet. Additionally, increasing swell is expected as Tropical Storm Isaias travels north/northeast across the Gulf. A Small Craft Advisory will likely be needed for the offshore Gulf waters beginning tomorrow afternoon or night, and for the nearshore Gulf waters by Friday. Otherwise, periods of showers and thunderstorms are expected to continue through the end of the week, before decreasing this weekend and early next week. NOAA Brownsville TX Office: Watches - Warnings - Advisories TX...None. GM...None. |
Brownsville TX Radar
Gulf Radar