052
FXUS64 KBRO 110518 AAA
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
1218 AM CDT Thu Jul 11 2024

...New AVIATION...

.SHORT TERM...
(Tonight through Thursday night)
Issued at 229 PM CDT Wed Jul 10 2024

Key Messages:

* Showers and thunderstorms this afternoon will wane in coverage
  this evening and tonight

* Another round of scattered to numerous showers and thunderstorms
  expected on Thursday

* Temperatures will hold to near seasonable levels and maybe even
  slightly below average through Thursday

* Outside of any convection, marine conditions will remain
  favorable through Thursday

Weakness in the 500 mb height pattern coupled with residual moisture
left behind from post-tropical cyclone (PTC) Beryl and interactions
with a persistent sea breeze will result in continued unsettled
weather through the short term forecast period (or through
Thursday).

Latest radar scans from the KBRO Doppler Radar and Mosaic MRMS Radar
continues to depict scattered to numerous showers and thunderstorms
over Deep South Texas and the Rio Grande Valley this afternoon. A
Special Weather Statement (SPS) was issued for southern Hidalgo
County earlier as winds at McAllen International Airport gusted to
48 mph from earlier thunderstorms. A few Flood Advisories have been
issued across the area as well. So far, the corridor from McAllen
into Weslaco and Mercedes have been the hardest hit with
incessant rainfall from the slow moving thunderstorms. Amounts are
ranging between 1-3 inches with locally higher amounts. A bit
more expected over the next few hours. Shower and thunder
(convective) activity will gradually wane in coverage and
intensity this evening before ending tonight. That said, for
tonight, expect for warm and very muggy conditions to continue.
Overnight lows are progged to be in the mid to upper 70s. There is
an slight/isolated chance for a shower or storm overnight
especially near the Texas Coast. Some patchy mist/fog is also possible
for tonight given the copious amounts of low level moisture and
relatively light winds.

On Thursday, another round of scattered to numerous thunderstorms
are expected once again given the combination of abundant moisture
left behind from Beryl, interactions with a sea breeze, and a nearby
shortwave. The main threats from any showers or thunderstorms will
be lightning and flooding due to heavy (torrential) rainfall in this
tropical, moisture-laden environment. The GFS and NAM models
continue to depict precipitable water (PWAT) values between 2-2.50
inches which is +1 to +2 STDEVs above normal (supportive of
very efficient rainfall production). With the mean LCL-EL (cloud
layer) winds expected to be between 5-10 kts, these storms will be
slow movers adding to the risk for flooding. Remember to avoid
flooded roadways and turn around, don`t drown!. Have categorical
(55-80%) PoPs for Thursday. The setup could be very similar to
today where showers and storms develop during the late morning
hours and persist into the afternoon hours. Showers and
thunderstorms will decrease in coverage and intensity during the
evening hours on Thursday. Temperatures may fall slightly below
normal depending on the timing of showers and thunderstorms. High
temperatures are forecasted to be in the upper 80s to lower 90s
(again slightly below normal).

Thursday night will continue warm and muggy with overnight lows in
the mid 70s to near 80F degrees. Dewpoint values will be at similar
levels. That said,, there is the chance for some patchy mist/fog
to develop Thursday night into Friday.

&&

.LONG TERM...
(Friday through next Wednesday)
Issued at 229 PM CDT Wed Jul 10 2024

Deep tropical moisture and an approaching inverted trough will
influence the region through Friday, supporting unsettled weather.
Friday rain chances will remain elevated in the 30-50 percent range,
some of which could be heavy. Rain chances should taper off on
Saturday, followed by more limited chances the rest of the forecast
from Sunday through next Wednesday.

We expect slightly drier conditions this weekend with models showing
more substantial drying early next week as the mid-level trough
shifts inland/west and 500 mb ridging builds over the lower
Mississippi Valley and extends back into East Texas. We expect a
gradual warming trend through the period as rain chances and cloud
cover decrease, with high temps ranging from the mid to upper 90s to
near 100 degrees, with a few more 100 marks possible each day. Low
temps will range from the 70s to near 80. Heat index values will
generally climb into the 105 to 110 degree range each afternoon, and
could briefly climb above 110 in some areas Tuesday and Wednesday
afternoons.

&&

.AVIATION...
(06Z TAFS)
Issued at 1213 AM CDT Thu Jul 11 2024

Tranquil conditions for the remainder of the overnight hours will
yield to convection on Thursday, and a prevailing has been inserted
into the TAFs to account for this convection. Overall, VFR will
occur at the aerodromes through the next 24 hours.

&&

.MARINE...
Issued at 229 PM CDT Wed Jul 10 2024

Tonight through Thursday night... Outside of shower and thunderstorm
chances, marine conditions will be favorable through Thursday with
light to moderate winds and low seas.

Friday through Monday night...We are forecasting light to moderate
southeast to south winds and low to moderate seas along the lower
Texas Coast through the period with surface high pressure
generally in control. We anticipate neither Small Craft Should
Exercise Caution nor Small Craft Advisory conditions.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             79  93  79  94 /  30  30  10  20
HARLINGEN               75  93  76  95 /  30  40  10  20
MCALLEN                 78  94  78  96 /  20  30  10  10
RIO GRANDE CITY         77  93  77  96 /  30  30  20  10
SOUTH PADRE ISLAND      81  88  82  88 /  30  30  10  10
BAYVIEW/PORT ISABEL     77  91  79  92 /  30  30  10  20

&&

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

&&

$$