301
FXUS64 KBRO 270543 AAB
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
1243 AM CDT Sat Apr 27 2024

...New AVIATION...

.SHORT TERM...
(Tonight through Saturday night)
Issued at 230 PM CDT Fri Apr 26 2024

Key message:
- Strong winds persist today and Saturday

Interaction between high pressure extending across the Gulf of
Mexico and lower pressured storm systems transiting across the
Plains will keep the local surface pressure gradient tight and the
South Texas wind machine on. Strong breezes are ongoing across the
CWA this afternoon, creating windy conditions. Winds will diminish
to a moderate to fresh breeze tonight, but winds will ramp up to a
strong breeze once again on Saturday. Conditions will border wind
advisory criteria, but will leave that decision to the next forecast
cycle as it still appears borderline.

Fire weather concerns have remained muted despite the stronger
winds. That is not to say that enhanced wildfire growth and spread
will not occur, just that the wind/relative humidity combination is
presently below specific thresholds. Rip current risk will continue
high, and I extended the rip current statement out to Sunday
morning, with additional extensions possible.

Temperatures will trend several degrees above average through the
short term, with lows in the 70s and highs on Saturday from the
upper 80s east to the upper 90s west. Skies will be partly to mostly
cloudy, with more sun out west than east in the afternoon and
overcast low clouds near the coast late night to early morning.

&&

.LONG TERM...
(Sunday through next Friday)
Issued at 230 PM CDT Fri Apr 26 2024

An upper-level trough over the Central Plains will traverse
further east Sunday, allowing for mostly zonal flow aloft over
Deep South Texas for the start of the workweek. By mid week, weak
upper level ridging looks to build over South Texas, though this
ridge will be quickly replaced by the next upper level trough by
the end of the period. A series of shortwaves moving through the
mid level flow will bring enhanced forcing to the area, increasing
potential for some convection to occur. Rain chances remain
fairly low through the period (20-30%), however multiple
opportunities for showers and thunderstorms are likely to occur.

At the surface, southerly to southeasterly winds look to be
persistent through the period, transporting plenty of warm, humid
air to the region. High temperatures through the period are
expected to remain in the 90s for most of the area, with areas
along the coast in the upper 80s. Likewise, low temperatures are
expected to remain in the 70s through the period.

The first opportunity for showers and thunderstorms will be
Sunday, as a cold front looks to stall to the northwest. Showers
and thunderstorms ahead of the cold front could move into northern
portions of the CWA, though limited instability and a potent CAP
will likely keep the best chances of convection further north.

The next opportunity for showers and thunderstorms looks to be
Monday night, when enhanced forcing from a passing shortwave could
convection developing along the Sierra Madre Mountains. Some of
these storms could make it to Deep South Texas, however a less
favorable environment closer to the coast could cause these storms
to dissipate before they make it that far. This cycle will
basically repeat itself Tuesday and Wednesday as additional
shortwaves move through.

The pattern changes slightly Thursday, as a cold front looks to
develops over North Texas and rapidly drops south. While recent
GFS and ECMWF runs both have the cold front moving through Deep
South Texas, they differ on the timing. With this system being
nearly a week out, uncertainty in either solution is fairly high,
however it is worth mentioning rain chances look to increase near
the end of the period with the potential passage of a cold front.

&&

.AVIATION...
(06Z TAFS)
Issued at 1241 AM CDT Sat Apr 27 2024

Increased southeasterly winds are expected to generally continue
through the TAF period, with gusts to 35 kts possible mid Saturday
morning into early Saturday evening. AWWs may be needed for HRL
and BRO for frequent gusts. MVFR ceilings are expected to improve
Saturday morning, with another round of MVFR ceilings arriving at
BRO and HRL Saturday evening.

&&

.MARINE...
Issued at 230 PM CDT Fri Apr 26 2024

Tonight through Saturday night...The surface pressure gradient
between high pressure extending over the Gulf of Mexico and a series
of low pressure areas moving across the Plains will cause fresh to
strong southeast winds and moderate to high seas through much of the
weekend. I extended small craft advisory conditions through 1 AM CDT
Sunday, when winds across the Laguna Madre may lower below 20 knots,
but persistent elevated Gulf seas may require further extensions of
the advisory for the Gulf marine zones.

Sunday through next Friday...Weakening pressure gradients will
allow wind speeds to decrease on Sunday, although stronger winds
over the Laguna Madre may warrant a Small Craft Advisory or Small
Craft Exercise Caution headline Sunday afternoon. While the winds
over the water look to decrease, seas will be slower to respond.
Wave heights may warrant Small Craft Advisories into Monday
morning for the coastal Gulf waters. Small Craft Exercise Caution
headlines may be needed periodically through the remainder of the
period, as a series of upper level shortwaves look to enhance
pressure gradients along the coast leading to stronger winds and
higher seas.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             76  91  76  90 /   0  10   0  10
HARLINGEN               74  94  74  91 /   0  10   0  10
MCALLEN                 76  95  76  93 /   0  10   0  20
RIO GRANDE CITY         74  93  74  93 /   0  10   0  20
SOUTH PADRE ISLAND      76  82  75  82 /   0  10   0  10
BAYVIEW/PORT ISABEL     74  90  74  88 /   0  10   0  10

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...High Rip Current Risk through Sunday morning for TXZ451-454-455.

GM...Small Craft Advisory until 1 AM CDT Sunday for GMZ130-132-135-
     150-155-170-175.

&&

$$

SHORT TERM...54-BHM
LONG TERM....60-BE
AVIATION...56-Hallman