textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 1103 PM CST Mon Nov 24 2025

- Above average high temperatures continue Tuesday.

- A cold front pushes through Tuesday night into Wednesday, bringing a low to medium (30-60%) chance of showers and thunderstorms across the region.

- More seasonable temperatures are forecast behind the front just in time for Thanksgiving, but won't stick around through the weekend.

DISCUSSION

Issued at 1103 PM CST Mon Nov 24 2025

Hot conditions are expected to continue Tuesday with high temperatures in the upper 80s to low 90s; well above normal for late November. Daily high temperature records will be neared, tied, or broken.

A cold front accelerating across South Texas will approach the region Tuesday, expected to pass overnight Tuesday. Tuesday afternoon, ahead of the front, rain chances of 10-20% are possible depending on the fronts speed and if convection is able to form ahead of the front. Along the front, prepare for low to medium chances of rain (30 to 60%) overnight into early Wednesday across the CWA, with a lingering low to medium chance of showers (20 to 40%) through Wednesday morning. HiRes guidance agrees that a line of showers will form along the front, but how connected this line will be across Deep South Texas is (and coverage of showers ahead of this line), is uncertain. Southeasterly winds allowing moisture to build along the Rio Grande is allowing for a higher chance of rain along the river. There is a chance for strong thunderstorms along the front with adequate instability, however, limited shear could damper strength - storms are expected to be sub-severe.

Gusty conditions return Wednesday following frontal passage. Cooler air will advect in behind the front, bringing more seasonable temperatures Wednesday and Thursday. Thursday morning low temperatures are expected to be the coolest of the forecast period, in the low 50s. These will not last long, as temperatures begin to rise Friday onward with southeasterly flow returning.

AVIATION

(06Z TAFS) Issued at 1103 PM CST Mon Nov 24 2025

Patchy MVFR clouds are scattered across the Rio Grande Valley tonight, which could pass over a site and temporarily reduce ceilings to 020-025kft. There is a chance of fog around sunrise this morning as winds lessen. This can reduce cigs/vsby to MVFR with localized IFR/LIFR. A frontal boundary currently draped across the region is maintaining elevated winds - if this holds its strength, wind may curb fog development. Expect southerly flow following sunrise Tuesday, shifting east through the afternoon.

Tuesday night, a cold front pushing through the region will bring medium chances of showers (40-50%) and thunderstorms to the RGV. Convection ahead of the front may bring showers Tuesday afternoon (10% chance).

MARINE

Issued at 1103 PM CST Mon Nov 24 2025

Generally favorable conditions with a low chance (20%) of rain are expected Tuesday. A cold front is expected to cross over lower Texas Waters Tuesday night bringing adverse conditions. Small Craft Exercise Caution headlines and Small Craft Advisories are likely Wednesday with a fresh northerly breeze and moderate seas. Rain chances increase to low to medium (30 to 50%) Tuesday night across the waters as the cold front pushes through, accompanied by gusty northerly winds. Lightning, gusty winds, elevated seas, and reduced visibility with heavy rain are possible in any storms. Winds and seas may briefly subside Thursday, but adverse conditions are expected to return for the weekend.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 87 71 88 70 / 0 0 10 50 HARLINGEN 90 68 89 65 / 0 0 10 50 MCALLEN 93 71 91 68 / 0 0 10 60 RIO GRANDE CITY 92 66 90 64 / 0 0 20 60 SOUTH PADRE ISLAND 83 75 83 73 / 0 10 10 50 BAYVIEW/PORT ISABEL 87 69 87 68 / 0 0 10 50

BRO WATCHES/WARNINGS/ADVISORIES

TX...None. GM...None.