781
FXUS64 KBRO 070315
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
1015 PM CDT Mon Oct 6 2025

...New KEY MESSAGES, DISCUSSION, MARINE...

.KEY MESSAGES...
Updated at 1006 PM CDT Mon Oct 6 2025

* Low to medium (20-60%) chances for isolated to scattered showers
  and thunderstorms are expected each day from Tuesday to Friday.

* Thursday will present a medium-high (30-70%) chance for showers
  and thunderstorms; highest chances along and east of IH-69C.

* Warmer than normal temperatures are expected to persist into next
  week.

* A Coastal Flood Statement remains in effect through Tuesday
  evening along the Lower Texas Coast beaches.

&&

.DISCUSSION...
Issued at 1006 PM CDT Mon Oct 6 2025

While there will be many dry hours, the increase in moisture and a
nearby weak shortwave trough will be the focus of day-to-day or near
day-to-day chances for isolated to scattered showers and
thunderstorms from Tuesday through Friday as the weather pattern
attempts to become slightly unsettled. Hi-res CAM guidances and
global forecasts models show precipitable water (PWAT) values
increasing to between 1.60-2.10" (1-2 STDEVs above normal) Tuesday
through Friday.

Sfc convergence along the seabreeze and/or an adequate amount of sfc
based differential heating will serve as lifting mechanisms for the
initiation of showers and thunderstorms during this time period.
Additional storms are possible thereafter via outflow boundaries
from nearby downdrafts. All said, any rain that develops could
produce heavy downpours, but ultimately will prove to be
beneficial given the overall dry trends of late. That said,
flooding is not expected to be a threat. The Storm Prediction
Center (SPC) does have the entire area outlooked under a general
risk for thunderstorms for Tuesday (SWODY2) and Wednesday
(SWODY3).

As far as probabilities, we continue to maintain a general low-
medium (20-60%) chance for showers and thunderstorms Tuesday through
Friday, with the best chance being anywhere from the late morning to
early evening hours and the greatest confidence/probabilities being
along and east of IH-69C. There is a period on Thursday where we
have a medium-high (30-70%) chance for showers and thunderstorms
with again the best chances being located along and east of IH-69C.

Temperature anomalies will continue to run warmer than normal for
this time of year, courtesy of a 588-591 dam heat ridge in place
overhead. This feature will generate daily daytime highs in the low
to mid 90s through early next week. Overnight lows will be in the
60s and 70s with 60s found across parts of the Northern Ranchlands
and occurring mainly late week into early next week (due to clearing
skies and increased radiational cooling).

Finally, a Coastal Flood Statement continues through Tuesday evening
based on observations seen from webcams along the South Padre Island
beaches earlier and observations/forecasts from the SPI Brazos
Santiago Station. The combination of long-period swell, proximity to
the full moon, and associated astronomical high tides will result in
narrow beaches near high tide cycles. High tide is expected at 2:39
AM CDT Tuesday morning and again at 4:56 PM CDT Tuesday afternoon.

&&

.AVIATION...
(00Z TAFS)
Issued at 618 PM CDT Mon Oct 6 2025

Through 00z Wednesday....Outside of any showers or thunderstorms
that are expected to develop on Tuesday, VFR conditions are
expected to persist through the 00z TAF cycle.

Any shower or thunderstorm will have the capabilities of reducing
cigs/vsbys to MVFR/IFR. Currently, we have low-medium (30-50%)
chances for showers or thunderstorms developing on Tuesday with the
best timing being anywhere from late morning to early evening.
Coverage, however, is expected to be isolated to widely scattered.
Have introduced Prob30 groups into the TAFs to account for the
potential for showers and thunderstorms on Tuesday.

Winds are expected to continue out of the southeast with speeds
between 5-15 kts through this evening before trending towards light
and variable tonight. Winds are expected to develop again out of the
east-southeast on Tuesday with speeds between 5-15 kts.

&&

.MARINE...
Issued at 1006 PM CDT Mon Oct 6 2025

Light to moderate winds and low to moderate seas are expected
through the forecast period, with 3-5 ft seas developing by
Wednesday and persisting through at least next weekend, before
potentially decreasing to 2-4 ft next week. Daily low to medium
(20-60%) rain chances return by Tuesday and continue through
Friday. Thursday will see medium-high (50-70%) chances. Locally
enhanced winds and seas are likely within any showers or
thunderstorms.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             77  92  77  90 /  10  60  50  60
HARLINGEN               73  92  73  90 /  10  50  30  50
MCALLEN                 77  96  77  94 /  10  50  40  50
RIO GRANDE CITY         73  96  73  93 /  10  30  30  40
SOUTH PADRE ISLAND      81  87  80  86 /  10  50  50  50
BAYVIEW/PORT ISABEL     76  90  76  88 /  10  50  40  50

&&

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

$$

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