textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Issued at 1042 PM CST Fri Nov 13 2026

- Isolated showers are possible (20%) during the day today.

- A Small Craft Advisory goes into effect at 5 PM today, lasting through early next week as winds and seas increase ahead of a cold front. Beach hazards are possible later this weekend.

- A cold front late Sunday/Monday will increase chances (20-70%) of showers and thunderstorms Sunday evening through early Monday, with greatest chances (50-70%) east of I-69C.

- The Storm Prediction Center has all of Deep South Texas in a Marginal Risk (level 1 of 5) for severe weather on Sunday. This is a conditional threat depending on the timing of the frontal passage.

- Temperatures will gradually warm through Sunday before the cold front lowers highs into 60s/lower 70s next week.

DISCUSSION

Issued at 1042 PM CST Fri Nov 13 2026

A mostly pleasant Saturday is expected outside of a low chance of isolated showers (20%), with high temperatures a touch warmer than yesterday, around 80. Saturday afternoon, cloud cover builds with deepening moisture, and winds become gusty thanks to a LLJ over central TX. A shortwave moving eastward across central TX will support a low chance (20%) of isolated showers developing over deep S TX, translating west to east through the late morning and afternoon. NBM backed off significantly on today's PoPs, but deep moisture has been outperforming models - opted to bump PoPs back up. Temperatures will continue to climb Sunday into the mid-80s ahead of a cold front.

By Saturday night, the majority of activity moves offshore. A cold front late this weekend/early next week will push through the region, supporting another round of showers and thunderstorms Sunday into Monday. Rain chances increase to low to moderate (20-50%) west of I-69C and moderate to high (50-70%) east, with highest probabilities near the coast. Model guidance indicates a line/cluster of showers moving south ahead of the front, but there remains disagreement on how far inland any showers or thunderstorms could reach. Latest guidance has been converging on frontal passage later Sunday (ranchlands) to overnight/early Monday (RGV), however, some guidance continues to bring precipitation into the area earlier Sunday afternoon. The Storm Prediction Center has placed deep S TX in a Marginal (level 1 of 5) risk of severe weather on Sunday. Front timing will be important regarding severe weather risk, as an earlier front would stop instability that could build in the warm sector.

Expect gusty winds behind the front Monday, and highs in the 60s (70s near the coast). Stay tuned for changes to the forecast as these may change. Tuesday morning will be chillier with lows in the 50s (60s near the coast), and highs similar to Monday. Models begin to diverge on the upper level pattern through the end of the period, but hints at another chance of rain Thursday.

Conditions begin to deteriorate at local beaches this weekend, with increasing swell and elevated seas increasing the risk of life- threatening rip currents. Minor coastal flooding is possible early next week behind the front.

AVIATION

(06Z TAFS) Issued at 1042 PM CST Fri Nov 13 2026

VFR conditions should prevail, with light and variable winds overnight primarily out of the southeast. There is a 30% chance of fog development at all sites under clear skies and light winds. Winds increase Saturday morning, becoming gusty to around 25 kts by the afternoon. Isolated showers moving west to east across the region may bring MVFR ceilings and briefly heavy rain, but confidence in coverage is low. Most likely timing would be 15-20Z at MFE, and 17-22Z at HRL and BRO.

MARINE

Issued at 1042 PM CST Fri Nov 13 2026

Conditions degrade Saturday with a tightening pressure gradient, as southeasterly winds increase through the day to moderate/fresh, and slight seas building overnight to moderate. Unfavorable conditions will continue into next week as a cold front pushes through Sunday/Monday. Small Craft Exercise Caution conditions are likely beginning this afternoon before a Small Craft Advisory goes into effect for all waters at 5 PM this evening for moderate seas offshore, and winds/gusts of 20+ kts across all waters. The Small Craft Advisory will stay in place through early next week as a cold front brings 6 to 9 ft seas and near-gale gusts Monday. There is a low to moderate chance (20-40%) of showers and thunderstorms Saturday night, increasing to moderate/high (40-90%) Sunday along the passing cold front, with greatest chances overnight Sunday.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 80 66 79 71 / 0 0 10 10 HARLINGEN 78 62 79 68 / 0 0 10 0 MCALLEN 79 63 81 69 / 0 0 10 0 RIO GRANDE CITY 79 60 81 67 / 0 0 20 0 SOUTH PADRE ISLAND 76 71 77 74 / 0 0 10 10 BAYVIEW/PORT ISABEL 78 66 78 70 / 0 0 10 10

BRO WATCHES/WARNINGS/ADVISORIES

TX...None. GM...Small Craft Advisory from 5 PM Saturday to midnight CST Tuesday night for GMZ130-132-135-150-155-170-175.