823 
FXUS64 KBRO 290549 AAB
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
1249 AM CDT Sat Apr 29 2023

...New AVIATION...

.SHORT TERM...
(Tonight through Saturday night)
Issued at 232 PM CDT Fri Apr 28 2023

Warm afternoon weather and elevated dew points in the upper 60s 
to lower 70s will help prime and destabilize the atmosphere for 
the next round of thunderstorms tonight. A potent, synchronized 
fast moving mid-level trough and quick moving surface cold front 
is moving into Central Texas now and will move through Deep South 
Texas by sunrise Saturday. The CWA is in a slight risk for severe 
weather, with the main threats being damaging winds and large hail
associated with strong to severe thunderstorms producing frequent
lightning.

Convection could initiate as early as 5-7 PM over Zapata/Starr 
Counties, with these storms strengthening and tracking east through 
the RGV anytime between 10 PM and 6 AM. The storms are likely to 
consolidate into a Mesoscale Complex (MCS) moving across the CWA as 
a squall line similar to last Sunday. Individual discrete cells 
could produce large damaging hail while the squall line will be the 
wind producer with damaging wind gusts possibly exceeding 70 mph in 
some locations. Heavy rainfall could become an issue as the 
thunderstorms track across the region.

One more issue with this system is the pressure gradient associated 
with the cold front. Cyclogenesis takes place over Central-Northeast 
Texas tonight will strengthen the pressure gradient along the Rio 
Grande Plains overnight into Saturday morning. A wind advisory may 
be needed Saturday morning for much of the CWA.

Mild and drier, breezy to windy weather will prevail Saturday with a 
potential wind advisory persisting into afternoon across portions of 
the RGV and along the coast. High temps will range from the 70s to 
lower 80s and humidity will be noticeably lower.

&&

.LONG TERM...
(Sunday through next Friday)
Issued at 232 PM CDT Fri Apr 28 2023

Near to slightly above temperatures are forecast most of the period 
with very limited rain chances. An H5 ridge will be in the process 
of building over the Desert Southwest, providing the County 
Warning Area (CWA) with lots of sunshine and pleasant conditions 
to Sunday into Tuesday. The ridge axis propagates east Tuesday 
and is forecast to nudge just east of the CWA by Wednesday night. 
Southwesterly flow aloft commences shortly thereafter. A few 
ripples in the mean flow will lead to slowly increasing rain 
chances later next week. As of now, kept rain chances less than 10
to 15 percent both Wednesday and Thursday with better rain 
chances Friday. Still time to sort things out for later next week.
In the meantime, enjoy some calmer weather conditions early next 
week.

&&

.AVIATION...
(06Z TAFS)
Issued at 1242 AM CDT Sat Apr 29 2023

Strong to severe thunderstorms moving across KMFE and may approach
KHRL and KBRO between 07-09Z. IFR to MVFR cigs in advance of a
cold front that will be sweeping across the region prior to
sunrise Saturday with skies expected to clear. Strong northwest
winds increasing behind the front with gusts 30-40 knots through
the afternoon. Winds decrease quickly by sunset. 

&&

.MARINE...
Issued at 232 PM CDT Fri Apr 28 2023

Tonight through Saturday Night...The main story will be a gale 
warning hoisted to start at 09Z for all waters in the wake of a cold 
front. It may take a couple of hours after 09Z for winds to ramp up 
to gale force. Hazardous conditions will continue through the short 
term.

Sunday through next Friday...Marine conditions are forecast to be 
much calmer Sunday thanks to high pressure overhead. As the high 
scoots over the Gulf of Mexico, the pressure gradient will tighten 
over the Lower Texas Coast Monday afternoon. This may lead to low 
end Small Craft Advisory criteria. Beyond that, high pressure builds 
over the western Gulf of Mexico with lighter onshore winds and more 
favorable marine conditions expected by the middle of the week.

&&

.FIRE WEATHER...
Issued at 232 PM CDT Fri Apr 28 2023

(Saturday)...Strong northwest winds gusting to 30-40+ mph and 
relative humidity values crashing into the 25-40 percent range 
behind an early Saturday morning cold front may heighten the fire 
weather risk; however, a mitigating factor is recent widespread 
rains and additional rain expected tonight. Fuels are wet, and 
forecast fuel dryness will likely remain "above normal moisture" on 
Saturday.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             55  85  64  84 /   0   0   0   0 
HARLINGEN               53  89  62  88 /   0   0   0   0 
MCALLEN                 56  89  63  89 /   0   0   0   0 
RIO GRANDE CITY         54  90  61  93 /   0   0   0   0 
SOUTH PADRE ISLAND      62  79  70  79 /   0   0   0   0 
BAYVIEW/PORT ISABEL     56  83  64  83 /   0   0   0   0 

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...Gale Warning from 4 AM early this morning to 6 PM CDT this 
     evening for GMZ130-132-135-150-155-170-175.

&&

$$

SHORT TERM...54-BHM
LONG TERM....58-Reese
AVIATION...59-GB