090
FXUS64 KBRO 121124 AAA
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
624 AM CDT Wed Jun 12 2024

...New AVIATION...

.SHORT TERM...
(Today through Thursday)
Issued at 237 AM CDT Wed Jun 12 2024

The relentless grip of oppressive 500 mb high pressure will be
loosened a bit for the BRO CWFA during this period. As the mid-
level ridge remains centered generally over southern New Mexico,
broad 500 mb low pressure will be in place over the western Gulf
of Mexico and along the Texas coastline. When combined with
precipitable water values that may increase to, and hover around,
2 inches, the result will be mainly isolated convection across the
BRO CWFA today through tomorrow, with the greatest areal coverage
of showers and thunderstorms anticipated for Thursday.

Temperature-wise, the relative absence of the 500 mb high, increased
cloud cover, and the opportunity for precipitation will result in
above normal temperatures through the period, and not well above
normal for a change. This will result in a HEAT ADVISORY not likely
for today and Thursday, and will instead manage the heat indices
with a SPECIAL WEATHER STATEMENT on both of those days.

&&

.LONG TERM...
(Thursday night through Tuesday)
Issued at 237 AM CDT Wed Jun 12 2024

While the mid-level ridge looks to hold strong going into the
weekend and continue to exert its influence over Deep South Texas
and the Rio Grande Valley. It does actually start to weaken a bit as
a shortwave swings across the Great Basin and through the Plains.
While this is occurring, an inverted trough axis will develop over
the eastern and central Gulf. At this current time and based on the
latest model analysis, Saturday could see some limited isolated
showers and thunderstorms. However, these showers and thunderstorms
are limited to the Lower Rio Grande Valley. GFS guidance does
indicate that starting on Saturday, the middle and upper levels of
the atmosphere will become more moist. However, that is a bit
dependent upon the previously mentioned inverted trough. The
current GFS shows the atmosphere remaining very moist for the
remainder of the long term forecast period. While there is plenty of
potential for rain and even periods of heavy rain. All this rainfall
would be very welcomed here in Deep South Texas with the ongoing
drought.

As for the temperatures for the long term forecast period, are
expected to be mostly in the range of 90s to triple digits. However,
the further into the long term forecast period one goes, the high
temperatures actually start to become a few degrees cooler. Thus by
Tuesday, the high temperatures are in the 90s for Deep South Texas
and the Rio Grande Valley. The heat indices continue to be rather
high, but below Heat Advisory through the long term forecast period
as well. As for the low temperatures, for the most part the
overnight lows are expected to be in the 70s, though some parts of
the region particularly the extreme southern areas could see some
low 80s creep in.

Shifting over to the tropics, there is the potential for some
tropical activity early next week. However the model guidance is
still holds some disagreements, but there are signs of some form of
either a Tropical Depression or a weak Tropical Storm. However, it
would seem that the most likely landfall at this time would be well
to our south around Veracruz. Further forecast shifts will need to
continue to monitor the model trends and see if they can come into a
better agreement. Climatological trends do show that the Bay of
Campeche is a good area for development of Tropical Cyclones, so
there is good reason to lean into the potential for the development
of a system in that region. Also considering that high pressure
over the central and eastern Gulf also adds to the notion of a
southerly development area. Further forecast shifts will also need
to watch for any sort of trends in the models that could see a
northern reformation that has occurred before with weak western Gulf
systems.

For those that are planning to make a trip to the beach during the
long term forecast period, early next week there is an expected
increase in the risk of rip currents along with some coastal
flooding as well due to the building swells coming from an elevated
pressure gradient creating a strong southeast flow.

&&

.AVIATION...
(12Z TAFS)
Issued at 623 AM CDT Wed Jun 12 2024

VFR will continue to be the rule at the aerodromes through the
next 24 hours.

&&

.MARINE...
Issued at 237 AM CDT Wed Jun 12 2024

Today through Thursday...Surface high pressure centered generally
over Louisiana will remain extended over the western Gulf of
Mexico through the period. This will produce light to moderate
winds and low to moderate seas along the Lower Texas Coast, with
neither Small Craft Should Exercise Caution nor Small Craft
Advisory anticipated to be needed.

Thursday Night through Tuesday...Light to moderate easterly winds
and low to moderate seas are expected with Tuesday night through
most of the weekend. Showers and thunderstorm chances start to
increase moving into the weekend, and could bring in some locally
elevated winds and seas, as an inverted trough axis approaches the
Lower Texas Coast. Moving into the early parts of next week, the
pressure gradient will become more enhanced leading to adverse and
hazardous conditions. A combination of Small Craft Exercise Caution
and Small Craft Advisory will be needed through Tuesday due to the
larger swell. There is potential for a tropical cyclone to develop
in the Bay of Campeche, which could mean that winds and seas could
actually be higher than what is current forecasted depending on how
that system develops.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             96  80  94  78 /  10  10  30  10
HARLINGEN               97  76  96  74 /  10   0  30   0
MCALLEN                100  79  97  77 /  10   0  20   0
RIO GRANDE CITY        100  79  97  77 /  10  10  10   0
SOUTH PADRE ISLAND      88  82  87  82 /  10  10  30  10
BAYVIEW/PORT ISABEL     92  79  92  78 /  10  10  30   0

&&

.BRO WATCHES/WARNINGS/ADVISORIES...None.

&&

$$