textproduct: Brownsville/Rio Grande Valley

KEY MESSAGES

Updated at 1219 PM CDT Mon Mar 30 2026

Key Messages:

* Unseasonably warm, dry, and at times breezy to windy conditions are expected to prevail through the workweek.

* A wetter, more active weather pattern change is expected to develop next weekend and potentially persist into the first full week of April.

* Showers and thunderstorms are expected to increase in coverage and probabilities from northwest to southeast Saturday-Saturday night in response to a cool front. Additional showers and storms are possible through Monday.

* Preliminary rainfall amounts between 1-2 inches with locally higher amounts are expected by Monday morning.

* Cooler than normal temperatures are expected over the weekend into early next week due to shower and thunderstorms.

* Adverse marine conditions can be expected through this week due to breezy to windy conditions from an enhanced sfc pressure gradient.

DISCUSSION

Issued at 1219 PM CDT Mon Mar 30 2026

Unseasonably warm and mostly rain-free conditions will prevail through the workweek across Deep South Texas and the Rio Grande Valley. An enhanced sfc pressure gradient on the western flank of a large Bermuda high will result in breezy to windy conditions throughout the week. Southerly winds 20-30 mph are expected to gusts as high as 40 mph nearly each day this week.

After months of perpetual dryness, a wetter and more active weather pattern change is slated for next weekend into the first full week of April. Finally, some much-needed rainfall in the form of showers and thunderstorms is set to arrive next weekend in response to an approaching cool frontal boundary. The latest forecast models have showers and thunderstorms expanding over the region in coverage and probabilities from northwest to southeast Saturday-Saturday night. Additional showers and maybe some thunderstorms will be possible post-frontal passage Sunday through Monday.

Ahead of and during this event, deep tropical moisture will advect into the region. High atmospheric moisture content with precipitable water (PWAT) values ranging between 1.5-2" will support the potential for appreciable rainfall amounts to occur. So far, anywhere from 1-2 inches of rain is expected to fall across Deep South Texas with locally higher amounts. Furthermore, given the supersaturated environment, heavy rainfall capable of localized flooding is possible, especially in instances of slow moving storms training over the same areas or areas that are flood prone. Given how far out in time we are, we're currently not outlooked under any excessive rainfall during this time.

High temperatures through the workweek will run warmer than normal with daytime highs ranging between the upper 80s to the upper 90s, and overnight lows ranging between the mid 60s to the mid 70s with 60s located over the Northern Ranchlands and 70s mainly along the Rio Grande Valley. Over the weekend into the early part of next week, showers and thunderstorms will result in cooler than normal temperatures with highs generally in the 70s and lows in the 50s.

AVIATION

(18Z TAFS) Issued at 1219 PM CDT Mon Mar 30 2026

Through 18z Tuesday....VFR conditions, by and large, are expected to prevail through the 18z TAF period. There could be a few MVFR clouds from time to time.

Southerly winds 7-15 kts are expected to prevail through the 18z TAF period. During the afternoon hours, winds could gusts as high as 25 kts or so.

MARINE

Issued at 1219 PM CDT Mon Mar 30 2026

Slightly more adverse marine conditions can be expected through the week as an enhanced sfc pressure gradient will result in mainly Small Craft Exercise Caution (SCEC) conditions. Showers and thunderstorm chances increase over the weekend into the early part of next week in response to a cool frontal boundary.

PRELIMINARY POINT TEMPS/POPS

BROWNSVILLE 69 86 71 87 / 10 20 0 10 HARLINGEN 66 89 68 91 / 0 20 0 10 MCALLEN 70 92 72 95 / 0 20 0 10 RIO GRANDE CITY 67 94 69 96 / 0 10 10 0 SOUTH PADRE ISLAND 72 79 72 79 / 10 20 10 10 BAYVIEW/PORT ISABEL 68 85 69 86 / 0 20 0 10

BRO WATCHES/WARNINGS/ADVISORIES

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