365
FXUS64 KBRO 011740
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
1240 PM CDT Fri Aug 1 2025

...New DISCUSSION, AVIATION, MARINE...

.KEY MESSAGES...
Updated at 1232 PM CDT Fri Aug 1 2025

* Relentless heat, some of the hottest temps of the year so far,
  and dry conditions will prevail through next weekend.

* HeatRisk will range between Moderate (Level 2 of 4) and Major
  (Level 3 of 4) through next week.

* Triple digit heat will be widespread and common along and west of
  IH-69E most days; heat indices will range between 105-115F degrees
  through next week.

* Heat Advisories and to a greater extent Special Weather Statements
  (SPSs) may be needed at times through next week.

* Generally favorable marine conditions will continue with low to
  moderate winds and seas, and mainly low rip current risk.

&&

.DISCUSSION...
Issued at 1232 PM CDT Fri Aug 1 2025

The theme of relentless heat, humid, rain-free, and at times breezy
conditions with elevated cooling demand/cooling degree days (CDDs)
will remain in place through the forecast period or through next
weekend, as a strong consensus amongst models and ensembles
suggest. In fact, some of the hottest temperatures of the season
are expected to take place this weekend through next week,
coinciding with peak climatological temperature averages. While an
elongated 591 dam subtropical heat complex will envelope the
Southern U.S. through next weekend, forecast models and ensembles
are showing an anomalously strong and sprawling 594-600 dam
subtropical Sonoran heat dome (+2 to +4 STDEVs) being a dominant
fixture over the Desert Southwest into Oklahoma and the west-
northwestern half of Texas.

As mentioned, some of the hottest temperatures of the year are
expected to take place this weekend through next weekend. That`s
when the Sonoran heat ridge "heat dome" will be the most expansive
across the Southwestern U.S. into the Plains. Over Deep South
Texas and the Rio Grande Valley 500 mb heights will range between
591-595 dam. Meanwhile, 1000-500 mb thickness heights are expected
to range between 580-585 dam. 850 mb temperatures ranging between
21-23C will translate to sfc high temperatures ranging between
95-106F degrees each day through next weekend. Triple digit
heating will be widespread encompassing a vast majority of real
estate across Deep South Texas and the Rio Grande Valley,
basically extending from IH- 69E and points west, nearly each day.
Tomorrow (Saturday) looks to be the hottest day or one of the
hottest days of the period. We also have to watch for temperature
trends during the middle parts of next week (Wednesday and/or
Thursday) as potential hottest days of the period candidates as
the aforementioned heat ridge expands again. Daytime high
temperatures along South Padre Island and beaches along the Texas
Coast will be in the upper 80s to near 90F degrees.

Given the very humid, tropical-like environment, heat indices will
generally range between 105-115F degrees each day through next
weekend. Our first Heat Advisories of the season and to a greater
extent (degree of confidence) Special Weather Statements (SPSs) may
be needed at times to acknowledge these hot temperatures through
next weekend. Given these hot temperatures, Moderate (Level 2 of 4)
and Major (Level 3 of 4) HeatRisk will be common through the
forecast period.

To learn more about HeatRisk, visit wpc.ncep.noaa.gov/heatrisk/.
To learn more about heat in general, visit www.heat.gov. Finally,
we urge everyone to take the necessary measures to protect
yourself from the heat. Heat is the #1 cause of weather related
deaths, nationally and for that matter globally. Drink plenty of
water, take frequent breaks, stay in a cool, air- conditioned
location/shelter, and check on your family, friends, elderly,
neighbors, and pets.

Rain-free conditions will prevail through the forecast period,
courtesy of the anomalously strong 594-600 dam Sonoran heat dome in
place driving strong subsidence over the region.

Rip current risk will mainly be low through the period, but there
could be instances of moderate rip current risk and breezy
conditions.

&&

.AVIATION...
(18Z TAFS)
Issued at 1232 PM CDT Fri Aug 1 2025

Through 18z Saturday....By and large, VFR conditons will prevail
through the 18z TAF cycle. Clouds, mainly diurnally driven, will
persist for the TAF sites (BRO/HRL) near the coast. Mainly SKC skies
will continue for MFE with strong mid-upper ridging overhead.

Winds will continue out of the south-southeast 5-15 kts through the
forecast period. This afternoon into this evening there could be
gusts as high as 20-25 kts, courtesy of increased mixing heights
and some brief thermal and sfc pressure gradients.

&&

.MARINE...
Issued at 1232 PM CDT Fri Aug 1 2025

Generally favorable marine conditions will prevail with low
to moderate seas and light to moderate south-southeasterly winds.
There remains a low chance of showers and thunderstorms offshore
next week.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             79  98  79  97 /   0  10   0  10
HARLINGEN               76 100  76 100 /   0  10   0  10
MCALLEN                 79 103  79 104 /  10  10   0  10
RIO GRANDE CITY         78 103  77 104 /  10  10   0  10
SOUTH PADRE ISLAND      80  89  80  89 /   0  10   0  10
BAYVIEW/PORT ISABEL     78  96  77  95 /   0  10   0  10

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&

$$

SHORT TERM...23-Evbuoma
LONG TERM....23-Evbuoma
AVIATION...23-Evbuoma