929
FXUS64 KBRO 031739 AAB
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
1239 PM CDT Thu Apr 3 2025

...New AVIATION...

.SHORT TERM...
(Today through Friday)
Issued at 229 AM CDT Thu Apr 3 2025

Well above normal temperatures and breezy to windy conditions
continue across Deep South Texas. A 500mb trough continues to deepen
into the Desert SW and West Texas, with a series of surface low
pressure systems swinging through the Southern Plains, this will
maintain dry conditions locally with an enhanced pressure gradient,
setting up a strong low level jet of 45 to 50 kts at 850mb along the
lower Texas coast this morning into this afternoon and again on
Friday, where the LLJ may be even stronger. A Wind Advisory may be
needed both today and Friday, with slightly higher chances on Friday
at the moment. Current observations across the RGV and VAD wind
profiles compared to this time last night are improved, but may
defer to the morning sounding once again for the final decision on
this shift.

HREF probabilities top off near 40 percent for wind gusts over 40
mph through this morning across the lower valley and lower Texas
coast, with the NBM less than 30 percent. For winds today and
Friday, ran with a blend of NBM90 and NBM95 for inland areas, hand
editing up across Cameron County where necessary. Winds should
remain breezy overnight and increase once again into Friday
afternoon.

Highs range from the low to mid 90s east to around 100 west today,
dropping a couple of degrees on Friday. There is a High Risk of rip
current statement and a High Surf Advisory along the lower Texas
coast in effect until further notice. Heat Risk remains moderate,
with Heat Indices or feels like temperatures topping off between 100
to 105 generally.

&&

.LONG TERM...
(Friday night through Wednesday)
Issued at 229 AM CDT Thu Apr 3 2025

Key Messages:

* Unseasonably warm temperatures to continue on Saturday ahead of an
  approaching cold front.

* Northerly winds strengthen late Saturday into Sunday following the
  cold fropa.

* Unseasonably cool temperatures begins late Saturday into Sunday
  and continues through Monday.

* A warming trend takes place Monday through Thursday of next week.

* Hazardous marine conditions continue into Monday before
  improving.

Global forecast models and ensembles continue to advertise a mid-
upper trough translating eastward from the Desert Southwest
Region into the Southern Plains late this week into this weekend.
This will help drive a cold front southeastward through Texas and
for that matter through Deep South Texas Saturday into Sunday. So
while mainly dry weather conditions are expected to prevail
through the long-term forecast period, cooler changes are expected
during the second half of the weekend into the early parts of
next week. Temperatures will then begin to moderate/warm back up
towards the middle part next week. It will be windy through the
weekend both ahead and behind the cold frontal passage.

We start of the extended Friday night into Saturday where
unseasonably warm, dry, and windy conditions will take place. Friday
night will feature warm and muggy conditions. Overnight lows are
progged to be in the 70s for much of Deep South Texas and the Rio
Grande Valley. Initially, during the early parts of evening and
early parts of the night, it will be breezy. However, southerly
winds are expected to wane as the pressure gradient over the region
relaxes and the pre-frontal trough approaches.

On Saturday, temperatures ahead of the approaching pre-frontal
trough and cold front will have the chance to warm into the upper
80s to lower 90s. A pre-frontal through is expected to pass
through the area on Saturday resulting in winds out of the south
shifting out of the north. While winds will shift in response to
this pre- frontal trough, an airmass change is not expected as the
colder air will be located further to the west behind an
approaching cold front.

Saturday night into Sunday, the cold front finally arrives resulting
in a notable cool down during this time period. Overnight lows
for Saturday night are progged to be in the 50s for most of the
area, some 30-40F degrees cooler than the high temperatures on
Saturday and 20F degrees cooler than the overnight lows from
Friday night. These values will also be cooler than normal for
early April standards. Following the passage of the cold front,
northerly winds are expected to strengthen Saturday night into
Sunday before weakening on Sunday. Finally, mainly dry weather
conditions are expected to persist Saturday night into Sunday.
Given that the cold front will be moisture starved, there is only
an isolated threat for showers across the southeastern portions of
Deep South Texas (i.e Hidalgo, Willacy, and Cameron Counties)
with the best chance being offshore.

With a full dry and cold air advection regime in place, Sunday is
expected to be the coolest of the week with daytime highs in the
upper 60s to lower 70s across the region. Sunday and Monday nights
will be chilly with overnight lows in the upper 40s over the
Northern Ranchlands to the low to mid 50s along the RGV. A warming
trend will commence to start the new workweek with mid 80s to the
lower 90s returning by Thursday of next week.

&&

.AVIATION...
(18Z TAFS)
Issued at 1234 PM CDT Thu Apr 3 2025

VFR and windy conditions with frequent southerly wind gusts
between 25-40 kts this afternoon. Winds slowly lower late this
afternoon but should remain breezy and gusty overnight with
occasional gusts as high as 30 knots. MVFR ceilings return after
sunset with occasional break in the ceilings due to the strong
winds aloft. A mix of SCT to BKN skies between 12-16Z Friday with
SCT clouds after 16Z.

&&

.MARINE...
Issued at 229 AM CDT Thu Apr 3 2025

Now through Friday...An enhanced pressure gradient due to low
pressure across the Southern Plains and northern Mexico will
maintain elevated winds across all coastal waters, driving elevated
seas and adverse marine conditions. Small Craft Advisories have been
extended and will likely continue until further notice.

Friday night through Thursday....Small Craft Advisories will likely
persist into Monday. Despite south-southeast winds subsiding and
shifting out of the north in response to a pre-frontal trough, sea
heights will still remain in high state Friday night through
Saturday. Following the cold fropa late Saturday, winds will
strengthen out of the north. These strong winds will persist
through Sunday and into Monday. During the day on Monday, winds
and seas look to subside giving way to improving marine
conditions. More favorable conditions return Monday evening and
persist through Thursday of next week with low to moderate seas
and light to moderate winds.

&&

.HYDROLOGY...
Issued at 229 AM CDT Thu Apr 3 2025

Due to historical rainfall last week across the mid to lower Rio
Grande Valley, water levels across the Arroyo Colorado, main
floodway, and north floodway remain elevated but continue to
improve. Water levels across the Rio Grande at San Benito and Lower
Brownsville have both fallen below action stage.

The Arroyo Colorado at the HAGT2 gauge in Harlingen is reporting
16.92 ft and falling. The gauge in Rio Hondo, ACHT2, is reporting
12.22 ft and falling.

The Rio Grande near San Benito, SBNT2, reached action stage of 44.0
ft around 12 PM Friday and crested to 54.04 ft early Sunday morning,
just shy of minor flood stage at 55.0 ft. Water levels at San Benito
fell below action stage of 44.0 ft around 7 PM Wednesday and are
currently 42.24 ft and falling.

The Rio Grande at Lower Brownsville, LOBT2, reached action stage of
24.0 ft around 5 PM Monday, and crested to 24.71 ft Tuesday
afternoon, short of minor flood stage at 27.0 ft. Water levels at
Lower Brownsville fell below action stage of 24.0 ft around 2 PM
Wednesday and are currently 23.1 ft and falling.

The main floodway through Weslaco at WSLT2 is at 17.25 ft and
falling, with the north floodway near Sebastian at SBST2 at 11.74 ft
and falling.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             91  76  90  76 /   0   0   0   0
HARLINGEN               93  73  92  74 /   0   0   0   0
MCALLEN                 98  77  95  76 /   0   0   0   0
RIO GRANDE CITY        100  74  98  71 /   0   0   0   0
SOUTH PADRE ISLAND      82  74  82  75 /   0   0   0   0
BAYVIEW/PORT ISABEL     89  74  88  74 /   0   0   0   0

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...Wind Advisory until 5 PM CDT this afternoon for TXZ251-254-255-
     351-354-355.

     High Rip Current Risk through Friday evening for TXZ451-454-455.

     High Surf Advisory until 7 PM CDT Friday for TXZ451-454-455.

GM...Small Craft Advisory until 7 AM CDT Saturday for GMZ130-132-135-
     150-155-170-175.

&&

$$

SHORT TERM...56-Hallman
LONG TERM....23-Evbuoma
AVIATION...59-GB