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307
FXUS64 KBRO 251932
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
232 PM CDT Wed Sep 25 2024

...New SHORT TERM, LONG TERM, MARINE...

.SHORT TERM...
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(Tonight through Thursday night)
Issued at 230 PM CDT Wed Sep 25 2024

The approach of an upper level trough is expected to also result in
the development of a closed low over the Central Mississippi River
Valley tonight. The forcing from this system should also support a
cold front pushing through Deep South Texas and the Rio Grande
Valley late tonight and into tomorrow morning. With PWAT values over
1.5 inches and CAPE around 1000 J/kg, the environment ahead of the
front is supportive of the development of showers and thunderstorms
both ahead and along the cold front itself. With a good amount of
shear and instability in the environment, some thunderstorms could
be strong, and there is even a low chance of severe thunderstorms
possible as well. SPC does have a marginal risk for northern Kenedy
County, while keep the rest of the area in a general thunderstorm
outlook.

As for the temperatures, starting with the high temperatures for
tomorrow, they are expected to be in the range of upper 80s to low
90s. Thanks to the passage of the previously mentioned cold front,
the the temperatures will be lower than they have been recently. In
addition the heat indices will also be much lower in the 90s as well
for tomorrow. The low temperatures for tonight are expected to be
mostly in the 70s, meanwhile the for Thursday night, the lows are
expected to be mostly in the 60s with a few places in the Lower Rio
Grande Valley in the low 70s.

Finally, the swell from Hurricane Helene is expected to arrive
tomorrow along the Lower Texas Coast. This will likely lead to a
higher risk of rip currents and some minor coastal flooding at area
beaches.
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&&

.LONG TERM...
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(Friday through next Wednesday)
Issued at 230 PM CDT Wed Sep 25 2024

A midlevel low over the Mississippi Valley will ingest the remnants
of Hurricane Helene before slowly lifting to the northeast this
weekend and into next week. At the same time high pressure over the
Desert Southwest into the Great Lakes will and slowly expand into
Deep South Texas through next week. At the surface, high pressure
will dominate in wake of a cold front that moves through tomorrow
morning. This will allow for much drier air to filter into the
region on Friday, leading to dry conditions through the weekend.
Moisture begins to return by midweek, with chances for rain along
the seabreeze returning.

Along the coast, long period swell from Helene will result in
increased wave heights and adverse beach conditions on Friday.
Enhanced rip current risk and minor coastal flooding will be
possible at beaches along the Lower Texas Coast.

As for temperatures, near normal temperatures will prevail through
the period, and along with lower humidity and dewpoints will feel
much more pleasant than previous weeks. Heat indices will remain
below 100 degrees through the period.
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&&

.AVIATION...
(18Z TAFS)
Issued at 1224 PM CDT Wed Sep 25 2024

VFR conditions are expected to persist through the TAF cycle at
all TAF locations. While skies are expected to be in the range of
mostly sunny to partly cloudy, the ceilings themselves are not
expected to be affected. There is the possibility that some IFR
conditions could occur again for MFE, but confidence is not high
enough to include in the TAF package. Winds are expected to remain
out of the southeast and could become more gusty by the end of the
period.

&&

.MARINE...
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Issued at 230 PM CDT Wed Sep 25 2024

Tonight through Tuesday Night...While mostly favorable conditions
are expected for tonight with light to moderate onshore flow and low
to moderate seas are expected for tonight. Swells from Hurricane
Helene and winds picking up after a cold frontal passage tomorrow
are likely to bring adverse conditions to the Lower Texas Coast,
thus Small Craft Exercise Caution headlines will be likely needed
for Thursday. Small Craft Advisories for the Gulf waters might also
be needed as well due to the larger wave heights.

Friday through Monday...Swell from Helene will lead to elevated seas
on the Gulf waters for Friday into early Saturday. Small Craft
Should Exercise Caution headlines or Small Craft Advisories may be
needed for the Gulf waters Thursday and Friday as wave heights look
to reach 6-7 feet. Seas are expected to subside over the weekend,
with favorable marine conditions prevailing through the remainder of
the period.
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&&

.PRELIMINARY POINT TEMPS/POPS...
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BROWNSVILLE             76  88  71  90 /  20  20   0   0
HARLINGEN               73  89  67  92 /  10  20   0   0
MCALLEN                 77  93  71  95 /  20  10   0   0
RIO GRANDE CITY         74  91  68  93 /  30   0   0   0
SOUTH PADRE ISLAND      79  86  78  87 /  20  20  10   0
BAYVIEW/PORT ISABEL     75  86  71  88 /  20  20   0   0
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&&

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

$$

SHORT TERM...64-Katz
LONG TERM....68-McGinnis
AVIATION...64-Katz