774
FXUS64 KBRO 270524 AAA
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
1224 AM CDT Fri Jun 27 2025

...New AVIATION...

.KEY MESSAGES...
Updated at 1219 AM CDT Fri Jun 27 2025

* Very warm and humid conditions with day-to-day chances for showers
  and thunderstorms will continue through the forecast period.

* Outside of the daily chances for showers and thunderstorms,
  marine conditions will generally be favorable through the
  forecast period.

&&

.SHORT TERM...
(Tonight through Saturday night)
Issued at 934 PM CDT Thu Jun 26 2025

The short term forecast period will feature the continued breaking
down of the 500 mb ridge or "heat dome" that resulted in a major and
widespread heat wave over the Midwest and Eastern CONUS earlier this
week. With Deep South Texas and the Rio Grande Valley on the
southwestern fringe of this weakening and shifting 500 mb heat dome,
temperature anomalies are expected to average out near climatology
through Saturday.

Overnight low temperatures tonight and Friday night are progged to
be in the low to mid 70s. Meanwhile, daytime high temperatures
Friday and Saturday are progged to be in the low to mid 90s, with
the exception of 80s along South Padre Island and the Lower Texas
Coast beaches.

Southeasterly flow near the sfc and aloft will continue to help keep
atmospheric moisture content elevated through Saturday. That said,
the combination of sfc based differential heating and elevated
precipitable water (PWAT) values will yield day-to-day chances for
showers and thunderstorms. Coverage is expected to be isolated on
Friday with low (5-15%) chances, and more isolated to scattered on
Saturday with low to medium (10-30%) chances. The highest
probabilities will be located closer to the Lower Texas Coast and
over the Gulf Waters.

&&

.LONG TERM...
(Sunday through next Friday)
Issued at 934 PM CDT Thu Jun 26 2025

Very warm and humid conditions will continue through the extended
forecast period amid a large-scale pattern shift with the
aforementioned 500 mb sub-tropical heat ridge shifting/retrograding
westward towards the Desert Southwest (4-Corners region).

In addition to the very warm and humid conditions that`s expected to
continue through the extended, global forecast models/ensembles are
suggesting that the pattern could become a bit more unsettled/wet as
we close the chapter of June 2025 and open the books to July 2025.
While most of the moisture in the form of showers and thunderstorms
will be connected/linked to the monsoonal flow over north-central
Mexico into New Mexico, there will be day-to-day chances for
showers and thunderstorms over Deep South Texas and the Rio Grande
Valley. According to multiple forecast solutions, a nearby
shortwave trough will be the impetus of day-to-day showers and
thunderstorms.

For the most part, probabilities and coverage are expected to be a
bit higher than prior days, courtesy of this feature nearby. The
best opportunity and coverage for showers and thunderstorms appear
to be Sunday (June 29) and Monday (June 30). Any convection that
develops will have the capabilities of producing heavy rainfall
and/or gusty winds.

Due to the increased cloud coverage and rain chances, temperatures
will continue to run near climatological levels for late June/early
July standards through the forecast period. Daytime high
temperatures will generally range from the low to mid 90s (80s
along/near the coast). Meanwhile, nighttime lows will be in the
70s through the period.

&&

.AVIATION...
(06Z TAFS)
Issued at 1219 AM CDT Fri Jun 27 2025

VFR conditions are expected to prevail through the majority of the
TAF period. Some isolated afternoon convection will be possible
along the sea breeze this afternoon, however the probability of
any of these showers or thunderstorms moving over a TAF site
remains to low for inclusion in the TAFs. In the event that one of
these storms does approach an airfield, ceilings and visibility
may briefly drop to MVFR or IFR levels. Otherwise, southeasterly
winds are expected to continue, with clear skies overnight giving
way to mostly sunny skies later this morning.

&&

.MARINE...
Issued at 934 PM CDT Thu Jun 26 2025

Generally favorable marine conditions will prevail through the
forecast period with low to moderate seas and light to moderate
southeast winds. Occasional gusts upwards cannot be ruled out
during the afternoon hours due to a locally enhanced pressure
gradient. Otherwise, daily chances for isolated to scattered
showers and thunderstorms will continue through early next week.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             92  77  92  78 /  10  10  20  20
HARLINGEN               94  74  94  75 /  10   0  20  10
MCALLEN                 97  77  97  78 /  10   0  10  10
RIO GRANDE CITY         96  76  95  76 /  10   0  10   0
SOUTH PADRE ISLAND      87  80  87  80 /  10  10  20  30
BAYVIEW/PORT ISABEL     90  77  90  78 /  10   0  20  20

&&

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

$$

SHORT TERM...23
LONG TERM....23
AVIATION...60-BE