-- Discussion containing changed information from previous version are highlighted. --
712
FXUS64 KBRO 011937
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
237 PM CDT Wed May 1 2024

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

.SHORT TERM...
-- Changed Discussion --
(Tonight through Thursday night)
Issued at 147 PM CDT Wed May 1 2024

The short-term forecast period will continue to feature a steady
state pattern, that being warm, humid and rain-free with continued
onshore flow. Morning and nighttime hours will continue to see
overcast skies while afternoon hours will see some breaks in the
overcast.

Daytime highs will be slightly warmer than normal while nighttime
lows will be warmer than normal. For tonight and Thursday night,
overnight lows are progged to be in the mid to upper 70s (some +4-8F
degrees above average). The high temperature on Thursday is expected
to be in the upper 80s to mid 90s (some +2-3F degrees above average)
across Deep South Texas and the Rio Grande Valley.
-- End Changed Discussion --

&&

.LONG TERM...
-- Changed Discussion --
(Friday through next Wednesday)
Issued at 147 PM CDT Wed May 1 2024

Shortwave energy, upslope flow and strong to extreme instability
will produce isolated to scattered convection initially across the
Sierra Madre in the late afternoon and evening on both Fri and
Sat. Most of this convection is expected to wane significantly
before reaching the Rio Grande Plains or Upper Valley given the
increasing cap strength and lack of forcing across our CWA. For
now, will maintain slight chance POPs for just Zapata county for
these Fri and Sat time periods. Otherwise, strong capping within
the 915-630 mb layer will keep our convective chances close to nil
through most of, if not all, of the extended forecast period.

The main weather story will be the building heat next week. A
broad strengthening mid/upper ridge axis will continue to expand
its grip and influence on our CWA next week. The result will be
increasing subsidence, even drier conditions, and rising temps.
Diminishing cloud cover will further add to the building heat. H8
temps by Wed will be 25-28 degrees Celsius! Widespread daytime
highs in the 90s through the weekend will gradually be replaced
with 100s during the Mon-Wed timeframe across inland areas,
especially west of I-69C. An expanding Major HeatRisk area by Tue
and Wed will prevail across areas west of I-69C. As for Heat
Indices, we could be looking at marginal heat advisories for this
same geographical area by Wed.
-- End Changed Discussion --

&&

.AVIATION...
(18Z TAFS)
Issued at 1217 PM CDT Wed May 1 2024

Through 18z Thursday....VFR to MVFR conditions were taking place at
the terminals as of this update under a SCT-OVC deck of cumulus
clouds with ceilings ranging from 2,000-2,500 feet AGL and
unrestricted visibilities. Latest GOES-16 visible satellite loop
depicts cloud coverage beginning to break up some over the local
forecast area. Breezy winds out of the southeast should help to
improve cloud coverage and ceilings some this afternoon. That said,
the expectation is for ceilings to return, albeit for a brief
period, to VFR levels this afternoon.

Later this evening, decreasing mixing heights coupled with copious
amounts of low level moisture with continued onshore flow should
allow for marine influences to increase once again in the form of
increased cloud coverage and a return of MVFR ceilings. Low MVFR to
IFR ceilings are possible tonight. During the day on Thursday,
ceilings are expected to improve/rise back into mainly MVFR levels.

Southeast winds will continue 10-20 kts with gusts at times up to 30
kts or so through the 18z TAF cycle.

&&

.MARINE...
-- Changed Discussion --
Issued at 147 PM CDT Wed May 1 2024

Tonight through Thursday night...Moderate winds may yield
periodic Small Craft Exercise Caution (SCEC) conditions.
Conditions are expected to range between a moderate chop to choppy
at the bay. Meanwhile, moderate seas are expected to continue
with wave heights between 4-6 feet. Elevated seas will result in a
MODERATE RISK for rip currents at the local beaches through
Thursday.

Friday through Wednesday...Moderate to occasionally strong
southeast winds will prevail through most of the period across the
coastal waters. Small craft caution conditions will be the
dominant hazard. However, at times in the afternoon and evening,
there will be marginal Small Craft Advisory conditions expected
for the Laguna Madre and nearshore waters given the enhanced
pressure and thermal gradients early next week. The rip current
risk will remain moderate to occasionally high throughout the
period.
-- End Changed Discussion --

&&

.PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --
BROWNSVILLE             78  89  78  91 /   0   0   0   0
HARLINGEN               75  92  76  93 /   0   0   0   0
MCALLEN                 78  93  78  95 /   0   0   0  10
RIO GRANDE CITY         77  95  77  96 /  10   0   0  10
SOUTH PADRE ISLAND      77  81  77  82 /   0   0   0   0
BAYVIEW/PORT ISABEL     76  87  76  88 /   0   0   0   0
-- End Changed Discussion --

&&

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

$$

SHORT TERM...23-Evbuoma
LONG TERM....80-MB
AVIATION...23-Evbuoma