107
FXUS64 KBRO 180523
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
1223 AM CDT Mon Aug 18 2025

...New AVIATION...

.DISCUSSION...
Issued at 1051 PM CDT Sun Aug 17 2025

Despite some subtle differences, the forecast over the next 7 days
continues to feature a weak mid-level high pressure over the Central
Plains shifting westward and expanding across the Four Corners
region by Tuesday. As a result, dry conditions continue across the
CWA through Monday, with PoP`s remaining below 10%. Meanwhile, mid-
level troughing expands over the Gulf, bringing an upward trend in
moisture, with probabilities increasing from a low (20-30%) chance
of showers and thunderstorms on Tuesday to a low to medium (30-50%)
chance on Wednesday, followed by a 20-40% chance on Thursday. Later
in the week, a trough over the mid-Atlantic extends southwestward,
further elevating PWAT values to near and above 2.0 inches,
resulting in a 30-50% chance on Friday and over the weekend.
Throughout the week, convection is expected to be diurnally driven
and brief in nature, occurring along the seabreeze boundary in the
late morning and afternoon hours with the highest probabilities
along and east of US-281/I-69 C, becoming more widespread in
coverage into the weekend. As PWAT`s increase, any convection that
develops brings the possibility of brief heavy downpours, lightning
and gusty winds. This wet pattern may continue into the beginning of
next week, though potentially beginning to shut off as recent runs
of the deterministic GFS and ECMWF hint at an eastward expansion of
the mid-level high residing over the Desert Southwest.

High temperatures continue to range from near to slightly above
average with mid 80`s at the beaches, mid to upper 90`s along and
east of I-69 E as well as nearly widespread lower 100`s further west
at least into Tuesday. Following, cloud coverage and probabilities
of rain increase, resulting in 90`s across all of inland deep south
Texas and the Rio Grande Valley by the weekend, while mid 80`s
continue along the immediate coast. Mostly a moderate (level 2/4)
heat risk is expected Monday and Tuesday, followed by a minor (level
1/4) to moderate heat risk Wednesday, through the weekend and into
next Monday as afternoon heat indices generally remain between 100
and 109 degF, though a few locations may experience higher apparent
temperatures for a brief period of time. At this team, heat indices
are borderline Special Weather Statement criteria for Monday across
portions of the coastal counties and Rio Grande Valley, though not
as high of a likelihood as today.

There is a low risk of rip currents through Monday.

&&

.AVIATION...
(06Z TAFS)
Issued at 1222 AM CDT Mon Aug 18 2025

Through 06z Tuesday....Flying conditions will mainly be VFR through
the 06z TAF period. There could be some MVFR low stratus around,
particularly during the overnight hours into the morning due to the
copious amounts of low level moisture left behind from recent rains
and lighter winds. Additionally, can`t rule out the low, yet non-
zero probability for some mist/fog developing as well overnight into
the morning hours for the same reasons described above.

Winds will continue out of the southeast 5-15 kts through the 06z
TAF period. Winds could gust as high as 20 kts during the afternoon
hours before waning later in the evening.

&&

.MARINE...
Issued at 1051 PM CDT Sun Aug 17 2025

Mainly light to gentle, moderate at times, southeasterly winds and
slight (1-2 feet) seas are expected to prevail throughout the
period, leaving for favorable marine conditions. Daily probabilities
of brief showers and thunderstorms increase to a low (20-30%) chance
Tuesday, increasing to a low to medium (30-50%) chance over the
weekend.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             96  77  96  78 /  10   0  20  10
HARLINGEN               97  74  98  73 /  10   0  20  10
MCALLEN                101  78 101  78 /  10   0  20  10
RIO GRANDE CITY        103  76 103  77 /   0   0  10  20
SOUTH PADRE ISLAND      88  80  88  80 /  10   0  20  20
BAYVIEW/PORT ISABEL     92  76  92  77 /  10   0  20  10

&&

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

$$

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