100
FXUS64 KBRO 071114
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
614 AM CDT Mon Jul 7 2025

...New AVIATION...

.SHORT TERM...
(Tonight through Tuesday night)
Issued at 1018 PM CDT Sun Jul 6 2025

A mid-level high pressure is expected to persist over the Desert
Southwest throughout the short term/Tuesday night, while a mid-level
low pressure regresses across the Gulf, nearing the Lower Texas
coast by Tuesday morning as an inverted trough, leading to chances
of convection along daytime seabreeze boundaries. Meanwhile, surface
high pressure over the Gulf continues to drive southeasterly winds
across deep south Texas and the Rio Grande Valley, with gusts up to
20-25 mph expected through Tuesday. Near to slightly below average
PWAT values persist through Monday, with a low (15-25%) chance of
showers and thunderstorms in the afternoon. As the trough nears
the Gulf coast on Tuesday, PoP`s increase to a low to medium
(20-30%) chance, spreading inland throughout the morning and
afternoon hours, likely with greater geographical coverage in
convection than Monday. On both days, PoP`s are highest near, and
east of, US-281. Heavy rain, frequent lightning and gusts up to
40 mph are possible within the strongest of storms. Additionally,
chances drop off overnight both nights. The mid-level trough
moves inland overnight Tuesday.

Slightly below average temperatures continue Monday and Tuesday
afternoons with highs in the low to mid 90s, mid 80`s along the
coast and overnight temperatures falling to the 70s inland to around
80 degrees near the coast. Afternoon heat indices are likely to
range mostly between 100-105 degrees, while a few areas may reach as
high as 108 degrees for a few hours in the afternoon. This leads to
a moderate (level 2 of 4) heat risk across the beaches and more
populated regions of the RGV, while the rest of deep south Texas
experiences a minor (level 1 of 4) heat risk.

The risk of rip currents remains low through the day Monday.

&&

.LONG TERM...
(Wednesday through next Monday)
Issued at 1018 PM CDT Sun Jul 6 2025

Due to the nearby trough and elevated PWAT values (possibly as high
as 1.85 in.), mostly cloudy skies linger into Wednesday, keeping
high temperatures in the low to mid 90s. Yet, a mid-level high
expanding over the Gulf is likely to increase subsidence aloft
slightly, thus limiting Wednesday afternoon PoP`s to a low
(15-25%) chance or less. Thursday into Friday, mid-level ridging
and subsidence aloft increase as PWAT`s fall below average,
resulting in mostly dry conditions, with PoP`s less than 10%,
though an isolated shower or thunderstorm or two can not be
completely ruled out. This will allow for more sunshine and
afternoon highs to rise back to normal levels, with mid to upper
90s inland (to as high as 100 degrees in Zapata County) along with
mid 80s at the beaches. Afternoon heat indices increase from
generally 100-105 degrees on Wednesday to 104-109 degrees for the
remainder of the period, with the area of moderate heat risk
expanding, more notably on Friday, from SPI and the more populous
areas of the RGV to the majority of the CWA over the weekend and
early next week. Overnight lows fall to the 70s inland to near 80
degrees at the coast, possibly rising a degree or two throughout
the later part of the week and into the weekend.

Low chances (15-20%) of afternoon seabreeze showers and
thunderstorms may return Saturday through next Monday as the mid-
level ridge over the Desert Southwest shifts westward toward the
West Coast, but confidence is low at this point.

&&

.AVIATION...
(12Z TAFS)
Issued at 609 AM CDT Mon Jul 7 2025

VFR conditions are expected at all airports, though there could be
some intermittent clouds that could temporarily drop to MVFR.
Confidence is low, so this was not included in the TAF package.
Winds will be southeasterly and could become gusty around 17-18z.
There is a small chance (less than 20%) of isolated showers and
thunderstorms throughout the day.

&&

.MARINE...
Issued at 1018 PM CDT Sun Jul 6 2025

Now through next Monday...Gentle to moderate southeasterly winds and
slight to moderate (2-3 feet) seas are expected to continue through
the period. Brief Small Craft Exercise Caution (SCEC) conditions
are possible across the Laguna Madre most afternoons, particularly
towards the later part of this week, when SCEC headlines may be
possible, due to a slight tightening of the pressure gradient.
Chances of showers and thunderstorms continue into Wednesday,
before mostly dry conditions return into the later part of the
week and over the weekend.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             92  79  93  77 /  10  10  20  10
HARLINGEN               94  75  93  75 /  20  10  20  10
MCALLEN                 95  78  96  77 /  10   0  20   0
RIO GRANDE CITY         95  77  95  75 /  10   0  20   0
SOUTH PADRE ISLAND      87  79  87  79 /  10  10  20  10
BAYVIEW/PORT ISABEL     90  77  90  77 /  10  10  20  10

&&

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

$$

SHORT TERM...65-Irish
LONG TERM....65-Irish
AVIATION...55-MM