297
FXUS64 KBRO 162346 AAA
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
646 PM CDT Thu May 16 2024

...New AVIATION...

.SHORT TERM...
(Tonight through Friday night)
Issued at 243 PM CDT Thu May 16 2024

Tonight, we will continue to see a dryline pushing into the Rio
Grande Plains, possibly making it to the mid-valley. A cold front
will also continue to slowly sag southeast, but remain northwest
of the CWA through tomorrow night. These two features along with a
mid/upper level trough moving over the region and outflow left
over from tonight`s thunderstorms well north of the BRO CWA will
give us a chance of seeing thunderstorms Friday. Chances have been
bumped up a bit from previous forecasts to 30 to 40%. Some of
this activity could be strong to severe across the northern
Ranchlands with forecast soundings showing CAPE values well above
3000 J/kg, lapse rates between 7C and 8C, and favorable shear.
The main threats from this activity will be large hail and winds
in excess of 60 mph. The Storm Prediction Center has put northern
portions of Jim Hogg, Brooks and Kenedy counties in a Slight Risk
for severe weather (Level 2 out of 5), the remainder of Kenedy,
Brooks and Jim Hogg and Zapata counties in a Marginal risk of
severe weather (level 1 out of 5). The best timing for severe
weather at this time looks to be Friday morning into Friday
afternoon. The remainder of Deep South Texas remains in a general
thunderstorms risk through the day Friday. All activity should
dissipate/move out of the area Friday evening.

Temperatures will be warm again tomorrow, with highs in the mid to
upper 90s. Combined with high humidity, "feels like" temperatures
are forecasted to be a bit higher than today, so a Heat Advisory
may be needed tomorrow afternoon. One caveat to this will be if
showers and thunderstorms move through the area, especially in the
Valley, or cloud cover remains, temperatures will not be quite as
high, and thus not warrant a Heat Advisory. Overnight lows will
remain warm and muggy, with lows in the 70s, with areas along the
cost and a few spots in the Valley hanging in the low 80s.

Otherwise, hazy conditions will persist through this evening, thanks
southerly winds and burning in Mexico and Central America. Haze
should clear out tomorrow.

&&

.LONG TERM...
(Saturday through next Thursday)
Issued at 243 PM CDT Thu May 16 2024

The main story for the long term will be warm temperatures through
next week. On Saturday, an upper level disturbance will move
northeast with high pressure quickly building in its wake. This will
lead to warming temperatures with triple digits returning to the Rio
Grande Plains Saturday afternoon with upper 90s across much of the
remainder of the CWA. The cool spot will be right along the coast
where temps range from the mid 80s to low 90s. The triple digits
will expand eastward through the week, reaching the coastal counties
by Tuesday. High humidity accompanying these hot temperatures will
lead to "feels like" temperatures exceeding 110 degrees in many
areas and Heat Advisories may be needed. Overnight temperatures will
remain warm and muggy with lows only falling into the upper 70s to
low 80s.

The NWS HeatRisk tool highlights a major risk of heat-related
impacts for those that are not properly hydrated or do not have
effective cooling in place through the week. No relief from the heat
is expected in the way of rainfall through the period with
subsidence in place.

&&

.AVIATION...
(00Z TAFS)
Issued at 622 PM CDT Thu May 16 2024

Currently, all TAF sites are experiencing VFR conditions but are
starting to fill in with MVFR ceilings at times and are expected
to become widespread following sunset. Meanwhile, winds will
lighten and MVFR ceilings will persist overnight and through
Friday morning. Celings will gradually lift into the afternoon
hours and there is a low probability of thunderstorms to affect
all aerodromes within the general timeframe of 18Z/19Z to 23Z/00Z
Friday afternoon into the evening.

&&

.MARINE...
Issued at 243 PM CDT Thu May 16 2024

Now through Friday night: Slightly adverse conditions will
continue on the Laguna Madre and Gulf waters through tonight with
elevated winds. On Friday, more favorable conditions return.
Friday into Friday night we could see some thunderstorms move over
the waters off the lower Texas coast which could lead to
localized high winds and seas.

Saturday through Wednesday: Light to moderate winds with seas of
generally 3 to 5 ft will persist through the week. A slighlty
enhanced pressure gradient each afternoon, especially next week,
could lead to periods of Small Craft Caution.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             79  96  78  96 /   0  20  10  10
HARLINGEN               77  95  75  97 /   0  30  10  10
MCALLEN                 79  96  78 100 /  10  30  10  10
RIO GRANDE CITY         77  95  76 100 /  10  40  20   0
SOUTH PADRE ISLAND      81  86  79  87 /   0  20  20  10
BAYVIEW/PORT ISABEL     78  92  77  92 /   0  30  10  10

&&

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

$$

SHORT TERM...68-McGinnis
LONG TERM....68-McGinnis
AVIATION...65-Irish/59-Bogorad