textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 1244 PM CDT Fri Jun 12 2026

* Light showers are ongoing and are expected to increase in coverage and intensity for starting Saturday morning.

* Moderate rain chances continue through the weekend, and increase to high (70-80%) Monday and Tuesday. Deep South Texas is under a Marginal (level 1 of 4) Risk of excessive rainfall both days.

* Heat Risk continues through the next week. Heat Advisories may be needed by late next week.

* A Moderate Risk of Rip Currents will increase to a High Risk of Rip Currents tomorrow. Swimming at area beaches this weekend will be unsafe.

DISCUSSION

Issued at 1244 PM CDT Fri Jun 12 2026

Shower activity has begun as a tropical wave arrives to Deep South Texas, creating unsettled and moist conditions favorable for convective development. Showers should be lighter this afternoon and evening, but are expected to increase in coverage tomorrow morning as the deepest moisture and instability begins to reach the area. Heavier showers and thunderstorms are expected Saturday and Sunday, and should be widespread but remain scattered. Precipitation chances this afternoon are fairly low (20 to 30%) and will be greatest along the sea breeze, but increase to around 50 to 70% tomorrow morning, and remain so through the weekend (with lower chances overnight).

It is most likely that most areas are expected to receive between 0.5 to 1 inch over the weekend. PWAT values are expected to be anomalously high with this surge of tropical moisture, with values ranging from 2 to 2.5 inches. Because the air is expected to be so moist, any showers and/or thunderstorms that form over the next few days will be efficient rainmakers and some will have the potential to produce locally heavier rainfall amounts of a few inches in a short period of time. Locally heavy amounts between 1 and 3 inches could occur on Saturday and Sunday for areas that happen to receive any heavier showers or thunderstorms.

Early next week, a weak upper-level shortwave will move across the Plains, which will bring a weak cold front to Texas. This cold front is expected to stall in Central Texas, with surface troughing expected to develop and linger just to our south in Northern Mexico. This stalled frontal boundary may drift a little further southward throughout the week while the surface low moves closer to our area. This, along with the continued presence of tropical air, will continue to support unsettled conditions along with shower and thunderstorm development through at least Wednesday, and possibly longer depending on the behavior of the stalled front and the surface low. In fact, the interaction of the unsettled tropical airmass with the frontal boundary is expected to bring our best rainfall chances (between 70 to 80%) for Monday and Tuesday.

In addition, the Weather Prediction Center has all of Deep South Texas in a Marginal Risk (level 1 of 4) for excessive rainfall for Monday and Tuesday. Areas that receive heavier rain over the weekend may be more prone to isolated flash flooding, as the ground will already be saturated. By mid-week, most areas in Deep South Texas should receive between 1 to 3 inches of rain, which includes the weekend totals. In some extreme localized cases, an area or two could see up to 5 to 6 inches between Saturday and Wednesday if they receive multiple pockets of heavy rainfall. Isolated flash flooding and nuisance flooding could become an issue in some areas that receive the heaviest rain.

Though it is unlikely at this time, there is still a low (10%) chance of tropical development in the Western Gulf over the next 7 days. The National Hurricane Center has extended the risk from the Bay of Campeche up to the Texas Coast. While Gulf water remains warm, atmospheric wind shear is overall unfavorable for development, which is keeping chances low. This will continued to be monitored this next week, especially as Gulf tropical moisture interacts offshore with the stalled frontal boundary.

Moderate (level 2 of 4) Heat Risk remains a concern over the next week, with some areas in Cameron and Willacy Counties reaching a Major (level 3 of 4) Heat Risk by the end of the week. Temperatures will be overall seasonal, but really high humidity will keep heat indices elevated. Heat Advisories may be needed by next Thursday for portions of Deep South Texas.

This tropical wave and frontal system is also expected to bring a host of beach hazards. Swell is expected to increase, along with wave heights. An ongoing Moderate Risk of Rip Currents increases to a High Risk of Rip Currents tomorrow morning as shower coverage increases and the seas become more disturbed. It will not be safe to swim at the beach this weekend. In addition, minor coastal flooding and beach run-up is also possible through the middle of next week.

AVIATION

(18Z TAFS) Issued at 1244 PM CDT Fri Jun 12 2026

VFR conditions are expected at all airports with light to moderate southeasterly winds. Shower activity and cloud coverage is expected to increase tomorrow morning, with a chance of potential shower activity.

MARINE

Issued at 1244 PM CDT Fri Jun 12 2026

Unfavorable marine conditions should persist throughout the week. SCEC conditions are expected starting tomorrow as winds increase on the Bay and Offshore, also with increased convective activity. Intermittent SCEC is also possible throughout the week. Small Craft Advisories may be needed Sunday for the Outer Gulf Waters due to elevated wave heights. Small Craft Advisories may be needed again by the latter part of the week due to elevated winds and seas. Scattered showers and thunderstorms are expected through at least Wednesday.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 80 90 81 92 / 40 70 20 50 HARLINGEN 77 90 78 91 / 20 70 20 60 MCALLEN 79 92 79 93 / 10 80 20 60 RIO GRANDE CITY 77 93 77 94 / 0 70 20 50 SOUTH PADRE ISLAND 83 86 83 87 / 30 60 40 40 BAYVIEW/PORT ISABEL 80 88 80 90 / 30 60 20 50

BRO WATCHES/WARNINGS/ADVISORIES

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