463
FXUS64 KBRO 271909
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
209 PM CDT Sat Apr 27 2024

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

.SHORT TERM...
(Tonight through Sunday night)
Issued at 207 PM CDT Sat Apr 27 2024

South southeast winds will decrease to a moderate breeze tonight as
low clouds thicken. Low temps will be in the mid 70s and rip current
risk will remain high.

The CWA will be in an SPC general thunderstorm outlook for Sunday.
The NAM shows a few coastal showers developing overnight, with
slightly increased areal coverage on Sunday. A cold front and dry
line will lie just upstream on Sunday. The two may merge just north
of the CWA, not quite pushing farther south. The NBM squeezes
isolated convection out over the Northwest CWA and the Northern
Ranchlands Sunday morning, but seems to end it by afternoon. High
temperatures will be mostly in the 90s except slightly lower at the
coast.

Sunday night should be relatively quiet. Low temperatures will be in
the 70s. There could be some in and out marine fog. Rip current risk
will remain high through Monday morning.

&&

.LONG TERM...
(Monday through next Saturday)
Issued at 207 PM CDT Sat Apr 27 2024

As the month of April comes to a close and we open the books to the
month of May, a low-amplitude, zonal to at times semi-zonal mid-
upper pattern coupled with the lack of any frontal passages as
indicated by the global models/ensembles suggest a dry and tranquil
weather pattern persisting through the long-term forecast period
(Monday through next Saturday).

Instability parameters (i.e. SBCAPE values between 2,000-3,000 J/kg,
Showalter values between 0 to -6, steep low-level lapse rates
between 6-9 C/km, steep mid-level lapse rates between 7-8 C/km)
would support the development of some diurnal thunderstorms nearly
each day next week especially during peak heating hours. However,
with no lifting mechanism in place and an unfavorable jet structure
with weak winds aloft, shower and thunderstorm development will be
limited. That said, can`t rule out an isolated/rogue pop-up shower
or thunderstorm developing on nearly any day next week. Maintained
low grade (20-30%) PoPs in the grids for parts of next week.
Otherwise, expect for dry and tranquil weather conditions to be the
theme through next week.

Given the meso-scale, synoptic, and mid-upper large scale layout,
temperature anomalies are expected to run warmer than normal for
late April/early May standards through all of next week and into
next weekend. High temperatures are progged to rise into the upper
80s to mid/upper 90s across Deep South Texas and the Rio Grande
Valley (RGV) during this time period with the warmest temperatures
over our western CWA. Overnight low temperatures are expected to
range between the low to mid/upper 70s. The humidity will also be in
place through the extended with dewpoints in the upper 60s to mid
70s.

&&

.AVIATION...
(18Z TAFS)
Issued at 1209 PM CDT Sat Apr 27 2024

MVFR at the TAF sites due to ceilings. Southeast to south winds
are increasing this afternoon, and some scattering out will be
possible. Otherwise, MVFR ceilings will build in again this
evening and tonight. Winds will diminish a bit tonight and won`t
be as strong on Sunday. Ceilings will scatter out to the west on
Sunday, and may include the TAF sites by late Sunday afternoon.

&&

.MARINE...
Issued at 207 PM CDT Sat Apr 27 2024

Tonight through Sunday night...The tight gradient between high
pressure across the Gulf of Mexico and lower pressure across the
Plains will produce fresh to strong southeast winds and moderate to
high seas through tonight. Winds may decrease slightly on Sunday.
For now a small craft advisory is in effect for the Laguna Madre
through Sunday morning and for the Gulf of Mexico waters through
Monday morning. Winds will weaken more Sunday night, but elevated
wave heights will likely persist on the Gulf waters into the long
term.

Monday through Saturday.....Small Craft Exercise Caution (SCEC)
conditions will dominate through much if not all of next week into
next weekend with moderate winds and seas (i.e. wave heights
over the Gulf Waters mainly between 4-6 feet).

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             76  92  76  90 /   0  10   0  20
HARLINGEN               74  94  74  93 /   0  10  10  20
MCALLEN                 76  95  76  93 /   0  10   0  20
RIO GRANDE CITY         75  94  73  94 /   0  10   0  20
SOUTH PADRE ISLAND      76  82  76  81 /   0  10  10  10
BAYVIEW/PORT ISABEL     75  90  75  88 /   0  10  10  20

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...Wind Advisory until 7 PM CDT this evening for TXZ254-255.

     High Rip Current Risk through Monday morning for TXZ451-454-455.

GM...Small Craft Advisory until 7 AM CDT Sunday for GMZ130-132-135.

     Small Craft Advisory until 7 AM CDT Monday for GMZ150-155-170-
     175.

&&

$$

SHORT TERM...54-BHM
LONG TERM....23-Evbuoma
AVIATION...54-BHM