Brownsville, Texas 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

828
FXUS64 KBRO 291953 AAA
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
253 PM CDT Thu May 29 2025

...New SHORT TERM, LONG TERM, MARINE...

.SHORT TERM...
(Tonight through Friday night)
Issued at 249 PM CDT Thu May 29 2025

Conditions are likely to remain dry tonight into Friday morning
across deep south Texas as weak upper level ridging and a mid-level
high pressure move over the region throughout tonight, enhancing
subsidence aloft. Low temperatures tonight should fall to the low to
mid 70s across the northern ranchlands and Rio Grande Plains as well
as mid to upper 70s across the RGV and the beaches. Meanwhile, a
cold front, currently in northern central Texas, will continue
drifting southward tonight into Friday, likely stalling near, or
just to the north, of the northern ranchlands and Rio Grande Plains
by early Saturday morning. Throughout Friday, a surface high
pressure over the eastern Gulf will transport moisture-rich tropical
air north-northwestward, resulting in rising precipitable water
(PWAT) values greater than 1.7 inches across the Rio Grande Valley
by Friday afternoon. As the mid-level high moves southeast of the
CWA and surface convergence enhances going into Friday afternoon,
subsidence aloft will decrease, particularly over the western CWA,
and winds will turn easterly, generating a low (20%) chance of
showers and thunderstorms along with partly to mostly cloudy skies.
Temperatures Friday afternoon are anticipated to reach the mid to
low 90s inland and mid 80s along the coast. Heat indices, or "real
feel" temperatures will be beneath Heat Advisory criteria, generally
ranging between 105-109 degrees for a few hours in the afternoon.

Throughout Friday evening and nighttime hours, minimized subsidence
aloft (over the western half of the CWA), increasing moisture
content and maximized onshore flow and surface convergence will
result in a low to medium (20-50%) chance of showers and
thunderstorms mostly west of I-69 C, with the highest chances along
the US border in Zapata and Starr counties. Depending on the amount
of instability and timing that convection is initiated Friday
evening, some of the first showers and thunderstorms to develop
could bring heavy downpours. Currently, we are expecting at least
0.15 inches of rain near I-69 C and at least 0.30 inches across
Zapata and western Jim Hogg counties. Isolated to scattered pockets
of greater than half an inch are possible west of I-69 C and
dependent on where the deeper convection initiates. However, we are
not anticipating more than nuisance flooding at this point as even
90th percentile NBM guidance suggests a low (10%) chance of
rainfall exceeding an inch. Friday night lows are expected to be
the same as tonight.

&&

.LONG TERM...
(Saturday through next Thursday)
Issued at 234 PM CDT Thu May 29 2025

The stationary boundary in the northern Ranchlands will keep
temperatures seasonable for the weekend and bring a low to moderate
chance of showers and thunderstorms Saturday (30-40%) and Sunday (20-
30%). The lingering frontal boundary creates a bit of uncertainty
with precip chances next week due to uncertainty in its
timing/movement.

Ridging at 200mb will provide subsidence over the CWA and allow for
temperatures to rise back to above-normal for early June.
Southeasterly winds become breezy to gusty with the meandering
surface low associated with the boundary, as well as increase low-
level moisture. This, paired with high temperatures in the mid 90s
to low triple digits, will allow apparent temperatures to rise into
the triple digits. A moderate to major risk of heat-related impacts
through next week are expected. Muggy, hot conditions will see
little relief, shy of a pop-up seabreeze shower during the
afternoon hours possible every day next week.

&&

.AVIATION...
(18Z TAFS)
Issued at 1219 PM CDT Thu May 29 2025

East-southeasterly winds of 12-13 knots and scattered to broken
VFR skies and conditions are being experienced at all terminals at
this hour and should continue through sunset this evening.
Following, winds are expected to become light and/or variable as
MVFR ceilings re-develop over all sites. Gradual lowering of
clouds is anticipated overnight, with guidance indicating
generally down to 1,000 to 1,500 ft or possibly LIFR or IFR at
KMFE, as is indicated by some short range high resolution models
and noted in the TEMPO from 10-14 Z Friday morning. A brief period
of 1-3 SM fog is possible as well at all sites. Following
ceilings are anticipated to slowly lift and clear throughout the
morning, reaching VFR possibly by the afternoon along east-
southeasterly winds of similar magnitude as today.

&&

.MARINE...
Issued at 234 PM CDT Thu May 29 2025

Tonight through Friday night...Gentle east-southeasterly winds and
slight seas are likely to continue through the period along with
mostly dry conditions, though isolated thunderstorms Friday into
Friday night not cannot be entirely ruled out.

Saturday through next Thursday...Gentle southeasterly winds and
slight seas provide favorable marine conditions this weekend.
Early next week, winds increase to moderate/fresh with seas
building to moderate by midweek. Small Craft Exercise Caution
conditions are possible for much of the midweek. There is a low
chance (10-30%) of showers and thunderstorms for every day in the
long term.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             78  93  79  90 /   0  10  10  30
HARLINGEN               76  94  75  90 /   0  10  10  30
MCALLEN                 78  97  78  92 /   0  20  20  30
RIO GRANDE CITY         76  96  75  89 /   0  20  40  30
SOUTH PADRE ISLAND      79  86  79  85 /   0  10  10  30
BAYVIEW/PORT ISABEL     78  91  77  88 /   0  10  10  30

&&

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

$$

SHORT TERM...65-Irish
LONG TERM....69-HK
AVIATION...65-Irish