textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 1042 PM CST Thu Dec 25 2025 * Moderate risk of rip currents continues at area beaches through Friday afternoon.

* Fog Friday morning may create hazardous traveling conditions with visibilities 3 miles or less. * Unseasonably warm temperatures continue through Sunday with highs in the mid to upper 80s.

* A tightened pressure gradient ahead of and behind a cold front passing through late Sunday night or early Monday morning could result in gusts up to 20-30 mph from Saturday into next Tuesday, with hazardous coastal and marine conditions likely.

* Showers and thunderstorms associated with the front is currently expected to increase chances of rain Sunday night through Monday night to as much as a medium (40-60%) chance Monday morning.

DISCUSSION

Issued at 1042 PM CST Thu Dec 25 2025

High pressure will continue to dominate, maintaining unseasonably warm temperatures through Sunday with highs in the 80s and lows in the 60s. A pattern shift is expected early in the week with a cold front Sunday night, bringing a chance of rain, elevated winds, and cooler temperatures to close out the year.

Nightly rounds of fog, with dense fog possible, continue into this weekend. Tonight and Friday morning is no exception; fog reducing visibility to 1-3 miles is expected. Localized dense fog can reduce visibility to a quarter mile or less. There is some uncertainty with when and where the densest of fog will occur, with wind being a key factor. Light winds at KBRO this evening have already allowed visibility to begin dropping. Latest short range guidance suggests dense fog will remain in the northern Ranchlands. Fog will mix out mid- morning as winds increase. A Special Weather Statement has been issued for counties east of Zapata for fog 3 miles or less through 8 AM CST, but an upgrade to Dense Fog Advisory is not out of the cards.

A strong cold front pushing through the region overnight Sunday into Monday will bring much cooler temperatures, breezy northerly winds, and a low to medium (30-60%) chance of showers and thunderstorms. Current guidance suggests a brief period of Wind Advisory-level winds along the immediate coast Monday. Fire weather conditions Monday may be a concern with elevated winds and dry air behind the front. High and low temperatures at or below normal are expected from Monday through midweek. There is a non-zero chance of low temperatures reaching or dipping below freezing in the northern Ranchlands midweek, but uncertainty is high this far out. We will continue to monitor trends and refine the forecast in the coming days to better highlight potential hazards.

AVIATION

(06Z TAFS) Issued at 1042 PM CST Thu Dec 25 2025

Fog is expected to develop as the night progresses, with patchy dense fog reducing vsby/cigs to MVFR/IFR/LIFR at all sites. Recent short range guidance has been trending towards improved visibilities tonight in the Rio Grande Valley. Uncertainty exists with overnight wind speeds - winds greater than ~6kt will minimize depth and coverage of dense fog. HRL's rural location increases confidence in dense fog presence. Conditions gradually return to VFR as southeasterly winds increase mid-morning Friday.

MARINE

Issued at 1042 PM CST Thu Dec 25 2025

Through Saturday, patchy to areas of fog are possible overnight. Favorable conditions will persist through this weekend, with southerly to onshore winds and slight seas, gradually increasing through the weekend with a tightening pressure gradient. Sunday night into Monday morning, a cold front will result in strong to near gale force winds with gusts to gale possible, building rough seas. Accompanying the front is a moderate chance (50 to 60 percent) of showers and thunderstorms Monday. Small Craft Advisories are likely Monday into Tuesday, with Gale Watch/Warnings possible. Conditions improve midweek.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 83 69 83 68 / 10 0 0 0 HARLINGEN 84 65 85 65 / 10 0 0 0 MCALLEN 87 69 88 69 / 0 0 0 0 RIO GRANDE CITY 86 65 88 67 / 0 0 0 0 SOUTH PADRE ISLAND 77 70 77 70 / 10 0 0 0 BAYVIEW/PORT ISABEL 81 67 82 66 / 10 0 0 0

BRO WATCHES/WARNINGS/ADVISORIES

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