584
FXUS64 KBRO 040509 AAA
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
1209 AM CDT Wed Jun 4 2025

...New AVIATION...

.KEY MESSAGES...
Updated at 1041 PM CDT Tue Jun 3 2025

 - Moderate (level 2/4) and/or major (level 3/4) heat risk
   continues into next Wednesday.

 - Low to medium (20-40%) chance of showers and thunderstorms next
   Tuesday and Wednesday.

&&

.SHORT TERM...
(Tonight through Thursday night)
Issued at 1041 PM CDT Tue Jun 3 2025

Ridging aloft is likely to continue to result in dry conditions for
deep south Texas and the Rio Grande Valley into Thursday as a mid-
level high pressure over central Mexico moves northeastward and
closer to our region. Although the probability is less than 10%, the
chance of a stray afternoon shower and/or thunderstorm can not be
completely ruled out as precipitable water (PWAT) values remain
mostly above 1.7 inches across the County Warning Area (CWA) and
possibly exceeding 2.0 inches, mainly east of I-69 C. Southeasterly
winds will continue at the surface, continuing to advect moist Gulf
air inland, leading to high temperatures on Wednesday and Thursday
peaking into the low to mid 90s across the coastal counties, mid to
upper 90s (mainly west of I-69 E) and up to 100 degrees, or a few
degrees warmer, across the Rio Grande Plains and portions of the mid
and upper RGV near the Rio Grande. This will lead to maximum heat
indices, or "real feel" temperatures, of 105-110 degrees on
Wednesday, with the possibility of Special Weather Statements
(SPS`s) for the middle and upper RGV as heat indices could briefly
hit 112 degrees in the afternoon. On Thursday, surface winds could
have a slight bit more of an onshore easterly component, resulting
in afternoon heat indices of 104-108 degrees, likely beneath SPS
criteria. All in all, this puts most of the CWA within a moderate
(level 2/4) heat risk on Wednesday and Thursday, but the hottest
locations mentioned are likely to experience a major (level 3/4)
heat risk on Wednesday. Overnight lows in the mid 70s are expected
across the northern ranchlands and mid to upper 70s are likely for
the Rio Grande Plains and the RGV, though temperatures may only drop
to the lower 80s across the lower RGV, SPI as well as southern
portions of the mid and upper RGV. High temperatures in the mid 80s
at SPI are expected.

&&

.LONG TERM...
(Friday through next Wednesday)
Issued at 1041 PM CDT Tue Jun 3 2025

Aside from a low (15-20%) chance of a stray shower and/or
thunderstorm east of I-69 E Friday afternoon, due to elevated PWAT
values along the western Gulf coast, ridging aloft is expected to
continue to result in mainly dry conditions across the CWA through
the weekend. Surface southeasterly winds are likely to continue for
the rest of the long term. Throughout the end of this weekend and
into next Tuesday, the mid-level high pressure is progged to
gradually drift westward into northern Mexico, thus decreasing
subsidence, or sinking air, aloft across deep south Texas. As
onshore southeasterly winds continue, the probabilities of showers
and thunderstorms increase to a low to moderate (20-40%) chance on
Tuesday.

Otherwise, the main focus of the long term continues to be the heat.
As mostly dry and sunny conditions continue through next Monday,
a slight warming trend is anticipated with low to mid 90s east of
I-69 C gradually warming to the mid to upper 90s on Monday while
upper 90s to lower 100s west of I-69 C warm to mostly lower 100s
by Monday. Daily afternoon heat indices are likely to also warm
from 105-110 degrees Friday through Sunday to as high as 110-115
degrees on Monday, with the hottest locations possibly across
portions of the mid and upper RGV and the eastern parts of the
northern ranchlands. These temperatures and heat indices could
result in daily SPS`s through the weekend and heat advisories
and/or SPS`s for the beginning of next week as afternoon heat
indices surpass 111 degrees for several hours. Altogether, at
least a moderate heat risk (level 2/4) exists across all of the
CWA for the long term with embedded pockets of major (level 3/4)
expanding across the RGV and northern ranchlands throughout the
weekend. As chances of precipitation and clouds increase slightly
on Tuesday and Wednesday, temperatures may cool by a few degrees,
most notably across the eastern portions of the CWA next Tuesday,
possibly down to mid to upper 90s next Wednesday.

&&

.AVIATION...
(06Z TAFS)
Issued at 1207 AM CDT Wed Jun 4 2025

Through 00z Thursday....Mainly VFR conditions are expected to
prevail through the 00z TAF cycle, though there could be a few MVFR
clouds around from time to time.

Winds will continue out of the southeast 5-15 kts through the 00z
TAF period. Southeast winds could gusts between 20-25 kts during the
day on Wednesday as mixing heights increase.

&&

.MARINE...
Issued at 1041 PM CDT Tue Jun 3 2025

Wednesday through next Wednesday...Gentle to moderate southeasterly
winds and slight to moderate (2-4 feet) seas are expected to
continue into the early part of next week. This will support
favorable conditions through the period. Increased moisture could
generate a low to medium (20-30%) chance of showers and
thunderstorms on Friday, but conditions are likely to remain dry
throughout the weekend as ridging aloft dominates the lower Texas
coastal waters. There is a low to medium (20-40%) chance of showers
and thunderstorms next Tuesday and Wednesday as ridging aloft
weakens.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             93  79  93  79 /   0   0  10  10
HARLINGEN               95  76  95  76 /   0   0  10   0
MCALLEN                 99  80  99  79 /   0   0   0   0
RIO GRANDE CITY         99  79  98  77 /   0   0   0   0
SOUTH PADRE ISLAND      88  81  87  81 /   0   0  10  10
BAYVIEW/PORT ISABEL     91  79  91  79 /   0   0  10   0

&&

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

$$

SHORT TERM...65-Irish
LONG TERM....65-Irish
AVIATION...23-Evbuoma