165
FXUS64 KBRO 120535 AAB
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
1235 AM CDT Sun May 12 2024

...New AVIATION...

.UPDATE...
Issued at 836 PM CDT Sat May 11 2024

Bumped up PoPs slightly to 20-30% and made adjustments to the WX
grids accordingly across our local forecast area based off radar
trends which depicts rain showers with embed thunder to our
southwest in Mexico. Will continue to monitor radar trends. Rest
of the going forecast remains on track. See previous discussion
below.

&&

.SHORT TERM...
(Tonight through Sunday night)
Issued at 154 PM CDT Sat May 11 2024

Weak upper level ridging over the Central Plains will help enhance
southerly low-level flow through the period. The stationary boundary
currently located over the area is expected to slowly shift north as
a warm front, facilitating the return of hotter temperatures to the
area. Low temperatures are expected to remain in the mid 70s
tonight, with high temperatures Sunday expected to reach into the
mid to upper 90s. Low temperatures Sunday night are expected to be a
bit warmer, staying in the upper 70s to low 80s. Warmer temperatures
and a slight increase in humidity will allow heat index values to
climb into triple digits, topping out a little below heat Advisory
thresholds Sunday afternoon.

Rain chances are expected to remain low through the period, with
most areas staying around 10%, though extreme northwestern parts of
the CWA could see rain chances around 15% tonight.

&&

.LONG TERM...
(Monday through next Saturday)
Issued at 154 PM CDT Sat May 11 2024

Progressive split flow to dominate through the coming week with
two or three mid-level troughs moving across the southern-central
tier states. Weak fronts associated with the troughs advance into
Texas possibly moving into Deep South Texas Tuesday and Friday as
of the latest model guidance. Rain chances, albeit low
(15-30%)remain still somewhat uncertain due to unknown proximity
of the front and track of the troughs and perturbations within the
split flow. Best chances remain on Monday/Monday night ahead of a
front. This is also the best opportunity for strong to severe
thunderstorms, WPC has all of Deep South Texas within a Marginal
Risk (1-5). Although most of the action will likely be north of
the region a highly unstable atmosphere and an elongated vorticity
lobe and the right rare entrance region of an upper jet nearby
may helps set off a few storms nearby. Otherwise, the low chance
of rain continues Tuesday through Thursday with potential for the
isolated activity to linger Friday and Saturday.

Temperatures to remain above normal through the week with Monday
indicated to be the Hottest day. Southerly flow in advance of a
front moving into Central Texas may allow for some compressional
heating. Model guidance indicates highs in the  mid 90s to lower
100`s away from the local beaches.  Dew points also inch up a degree
or two (they can`t get any higher) pushing the heat indices into the
110-115 range providing a medium to high chance for Heat
Advisories for the Mid and Lower RGV. Tuesday-Wednesday look to be
not as hot as winds will take on an slight easterly component
(cooler Gulf waters). Temperatures then rebound Thursday and
Friday as winds veer ahead of another weak frontal boundary.

&&

.AVIATION...
(06Z TAFS)
Issued at 1229 AM CDT Sun May 12 2024

Light to moderate east to southeast winds and generally VFR
conditions prevail across Deep South Texas early this morning.
MVFR ceilings are expected to develop in the next few hours and
persist through the mid-morning. Ceilings will gradually lift to
VFR later this morning into the afternoon. Light southeast winds
this morning will become moderate to gusty later this morning
into the afternoon. MVFR ceilings are expected to return late in
the period.

&&

.MARINE...
Issued at 154 PM CDT Sat May 11 2024

Tonight through Sunday night: Generally light to moderate
easterly to southeasterly winds and slight to moderate seas are
expected through the short term period. A strengthening low
pressure system over Central Mexico is expected to tighten
pressure gradients Sunday afternoon, leading to stronger winds
over the Laguna Madre and Nearshore Gulf waters. Small Craft
Should Exercise Caution headlines will likely be needed, and a
Small Craft Advisory may be needed as well, though conditions look
borderline at this time.

Monday through Saturday...A series of weak frontal boundaries
(warm and cold) to approach or move into the northern portions of
the Gulf of Mexico this coming week. Pressure gradient remains
weak to modest providing light to moderate winds and a slight to
occasional moderate sea state.

 &&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             78  91  79  95 /  10  20  10  20
HARLINGEN               76  94  77  98 /  10  10  20  20
MCALLEN                 78  96  78  99 /  10   0  20  20
RIO GRANDE CITY         76  97  76 100 /  10   0  20  20
SOUTH PADRE ISLAND      79  85  80  86 /  20  10  20  20
BAYVIEW/PORT ISABEL     77  90  77  92 /  10  10  20  20

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             79  95  78  93 /  10  20  10  20
HARLINGEN               77  98  76  94 /  20  20  10  10
MCALLEN                 78  99  78  98 /  20  20  10  20
RIO GRANDE CITY         76 100  76  98 /  20  20  10  20
SOUTH PADRE ISLAND      80  86  79  85 /  20  20  10  10
BAYVIEW/PORT ISABEL     77  92  77  89 /  20  20  10  10

&&

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

$$

SHORT TERM...60-BE
LONG TERM....59-GB
AVIATION...63-KC