textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 1120 AM CST Tue Dec 2 2025

- Chances of rain increase to a low to medium (30-60%) chance inland and to a medium to likely (60-80%) chance near the coast by Thursday evening in association with an offshore coastal low.

- Up to half an inch of rain is possible near the immediate coast line Thursday into Friday.

- Adverse marine conditions return on Thursday in wake of a cold front, with Small Craft Exercise Caution and/or Small Craft Advisory headlines possible.

DISCUSSION

Issued at 1120 AM CST Tue Dec 2 2025

A surface high pressure over northeastern Texas continues to push a cold front southward and offshore throughout the day today, reducing chances of rain across Deep South Texas to less than 10% tonight into tomorrow morning. A developing offshore coastal low increases probabilities of rain to a low to medium (20-40%) chance across coastal and island areas tomorrow afternoon through tomorrow night. A cold front pushing through Thursday morning further increases probabilities of precipitation (PoPs) from a low to medium (20-50%) chance in the morning, highest near the coast, to a low to medium (30-60%) chance inland and a medium to high (60-80%) chance across coastal and island areas throughout Thursday evening. Overnight Thursday, PoP's decrease to a low (15-20%) chance over the northern ranchlands and a low to medium (30-40%) chance closer to the immediate coast by Friday morning, further decreasing throughout the day, though a low to medium (30-40%) chance returns across the County Warning Area Friday night as further rounds of high pressure surge through, enhancing convergence. Currently, we are anticipating as much as a half inch of rain near the immediate coastline from Thursday into Friday. Following a low (15-20%) chance of rain near the Lower Texas coast line on Saturday morning, drier conditions prevail into the beginning of next with the next possible chances of rain possibly by next Tuesday.

Temperatures continue to remain well below average as highs today only reach into the upper 50s/lower 60s, falling to the 40s and 50s tonight inland and low 60s at the beaches. As the surface high pressure continues northeastward to the mid-Atlantic by tomorrow night, southeasterly to easterly winds return tomorrow into Thursday, warming highs back to near normal, into the upper 60s and and 70s as well as 50s/60s tomorrow night. Temperatures plummet again Thursday night behind the front, with 40s/50s Friday morning only rising to the 50s/60s in the afternoon. More seasonable temperatures return Saturday and onward, possibly maximizing in the low 80's on Sunday.

AVIATION

(18Z TAFS) Issued at 1120 AM CST Tue Dec 2 2025

Ceilings have risen to VFR levels, which should prevail through the afternoon and early evening with peaks of sunshine becoming more plentiful along with northerly winds of about 9-12 knots. MVFR ceilings are expected following sunset at KBRO and KHRL while VFR prevails at KMFE along with calm or light and variable winds. Late tonight and into early tomorrow morning, MVFR ceilings lower to IFR, possibly lower, at KHRL and KBRO while KMFE lowers to MVFR before ceilings gradually rise back to VFR by tomorrow afternoon across all terminals along with gentle to moderate northerly winds similar to today.

MARINE

Issued at 1120 AM CST Tue Dec 2 2025

Gentle to moderate northerly winds and moderate (4-6 ft) seas during the day today become southeasterly to southerly with slight to moderate (2-4 ft) seas by tomorrow morning. A cold front passes through Thursday morning, likely bringing Small Craft Exercise Caution (SCEC) conditions as moderate to fresh northerly winds arrive in its wake, elevating seas. A Small Craft Advisory may be possible. Conditions improve on Friday, with more ideal conditions lingering into the beginning of next week. Chances of rain increase from a low to medium (20-40%) chance tomorrow to as much as a medium to likely (69-90%) chance by Thursday evening. Probabilities gradually decrease to a low (less than 10%) by Sunday, possibly increasing again next Tuesday.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 59 56 75 68 / 20 10 20 10 HARLINGEN 58 54 74 64 / 10 10 10 10 MCALLEN 60 55 75 66 / 10 0 0 10 RIO GRANDE CITY 63 51 74 62 / 10 0 0 10 SOUTH PADRE ISLAND 63 63 76 71 / 20 10 40 30 BAYVIEW/PORT ISABEL 59 58 74 66 / 10 10 20 20

BRO WATCHES/WARNINGS/ADVISORIES

TX...High Rip Current Risk until 6 PM CST this evening for TXZ451-454- 455.

GM...Small Craft Advisory until 6 PM CST this evening for GMZ130-132- 135-150-155-170-175.