textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 1255 PM CDT Sun Apr 19 2026

Key Messages:

* Medium to likely chances of rain prevail over the next 24 hours, with the possibility of thunderstorms and heavier rain tonight into tomorrow, possibly bringing an additional 1-2 inches of rain along/east of US-281 by Tuesday afternoon.

* Minor nuisance flooding in low-lying areas is possible within heavier downpours late tonight into tomorrow, when the bulk of the rain is likely to fall.

* Breezy to windy northeasterly winds and moderate to rough seas today continue to produce dangerous waves, minor coastal flooding and adverse marine conditions into at least tonight as well as life-threatening rip currents through at least tomorrow afternoon.

* Much cooler temperatures and overcast skies persist as well, rising from the 50s/60 today and tonight into the 70s tomorrow.

* Sunnier skies resumes Tuesday along with a warming trend into this upcoming weekend.

DISCUSSION

Issued at 1255 PM CDT Sun Apr 19 2026

Overnight last night, a cold front passed through all of Deep South Texas, leaving much cooler temperatures, cloudy skies, breezy north-northwesterly to northeasterly winds (gusting to 15-25 mph) areas of drizzle inland and intermittent light to moderate showers from coastal troughing along/near the coast. The cold front and associated surface low pressure remain offshore to our southeast at this time. Throughout this afternoon and into tonight, short term high resolution models indicate surface high pressure shifting eastward into the southern US, setting up southeasterly return flow over the Gulf, pushing the surface low northwestward over our region tonight into tomorrow morning; on- and-off light shower development this afternoon increases in coverage and intensity tonight, with a medium to likely (50-90%) persisting into tomorrow morning. A few thunderstorms are possible as well. As the low slowly moves west toward Mexico during the day tomorrow, easterly winds return on its backside and diurnal instability continue developing showers and isolated thunderstorms, with a medium to likely (40-70%) chance of rain during the day followed by a low to medium (30-50%) chance of light rain tomorrow night, lingering through Tuesday afternoon. The best chances of rain and the highest rainfall totals through Tuesday afternoon are likely to be along/east of US-281, where an additional 1-2 inches is expected, though a few locations could receive over 2 inches where heavier rain sets up. Although WPC has removed the Marginal Risk of excessive rainfall, minor nuisance flooding in low-lying areas remains a possibility tomorrow. Half an inch to an inch is expected further west, with the lower chances of rain and lesser amounts across the Rio Grande Plains and the Upper RGV.

As the low moves out of Deep South Texas by Tuesday evening, dry conditions (less than 10% PoPs) should return Tuesday night and into the remainder of this week, though coastal troughing could maintain a low (15-20%) chance for a few showers along the coast into Wednesday. Cloudy skies and cold air advection result in high temperatures only rising by a few degrees this afternoon and falling a few degrees tonight, remaining in the 60s along/east of US-281 and in the 50s further west. Easterly flow tomorrow leads to highs in the 70s in the afternoon before falling to the 60s tomorrow night. Breaks in overcast skies are expected on Tuesday, gradually becoming sunnier through this upcoming weekend, warming from the 80s on Tuesday into the 80s/90s on Wednesday on Thursday, followed widespread 90s over the weekend.

Breezy to windy conditions along the Lower Texas coast and coastal waters continue to lead to breaking waves of 5 to 7 feet and minor coastal flooding, with a High Surf Advisory in effect until 7 PM this evening and a Coastal Flood Advisory until 10 PM tonight. Factoring in wave periods of 7-8 seconds with elevated seas, a Rip Current Statement/High Risk of Rip Currents remains in effect through tomorrow afternoon. Swimming at the beaches is not recommended as life-threatening currents and dangerous surf prevail.

AVIATION

(18Z TAFS) Issued at 1255 PM CDT Sun Apr 19 2026

Blustery conditions in wake of last night's cold front continue to lead to intermittent light rain showers, 4-6 SM vis. and IFR ceilings continue through the remainder of the 18Z TAF cycle. Northerly winds of around 10-15 with gusts to 15-20 knots continue through this afternoon, becoming light and variable overnight. There is a low chance for thunderstorms tomorrow by mid-day.

MARINE

Issued at 1255 PM CDT Sun Apr 19 2026

Fresh to strong northeasterly winds and moderate seas this afternoon become moderate to fresh easterly winds and moderate seas overnight tonight into tomorrow night. A Small Craft Advisory remains in effect until 10 PM tonight. Gentle to moderate southeasterly winds and slight to moderate seas resume Tuesday. A medium to likely (40- 80%) chance of rain continues into tomorrow night with a low to medium (30-60%) chance lingering into Wednesday. There is a low chance of thunderstorms tonight into tomorrow.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 65 78 70 82 / 80 60 50 40 HARLINGEN 62 78 66 84 / 80 70 50 40 MCALLEN 62 78 68 86 / 80 60 50 40 RIO GRANDE CITY 58 76 65 86 / 80 50 50 30 SOUTH PADRE ISLAND 68 76 73 78 / 80 70 50 40 BAYVIEW/PORT ISABEL 65 78 69 82 / 80 70 50 40

BRO WATCHES/WARNINGS/ADVISORIES

TX...Coastal Flood Advisory until 10 PM CDT this evening for TXZ451- 454-455.

High Rip Current Risk through Monday evening for TXZ451-454-455.

High Surf Advisory until 7 PM CDT this evening for TXZ451-454- 455.

GM...Small Craft Advisory until 10 PM CDT this evening for GMZ130-132- 135-150-155-170-175.