958
FXUS64 KBRO 290523 AAA
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
1223 AM CDT Fri Aug 29 2025

...New AVIATION...

.KEY MESSAGES...
Updated at 1220 AM CDT Fri Aug 29 2025

 - Moderate to Major (Levels 2 to 3 of 4) Risk of excessive heat
   through Saturday with heat indices of 105-111.

 - Mostly rain-free conditions expected through Saturday; rain
   chances increase Sunday to low (20%) and moderate (40-50%)
   Monday and Tuesday.

&&

.DISCUSSION...
Issued at 1030 PM CDT Thu Aug 28 2025

The main concern going into this holiday weekend will continue to be
heat, as subsidence with low-level moisture brought by south-
southeasterly winds maintains afternoon heat indices into the
triple digits each day through Saturday. Near to slightly above
average high temperatures persist, but a Moderate to Major (levels
2 to 3 of 4) risk of heat-related impacts are expected. Heat
indices from 105-111 are possible across the region, with the
highest values expected in the mid-upper RGV and along US-77. It
is imperative to continue practicing heat safety by staying
hydrated, limiting time outdoors in direct sunlight, and taking
frequent breaks. For more resources on staying safe in the heat,
visit weather.gov/heatsafety.

Mid-level ridging will keep rain chances low, generally less than
10%, through Saturday. As this ridge shifts west, deeper layer
moisture builds, bringing PWAT values around 2" (between 75-90th
percentile of climatology). Shortwaves on the eastern periphery of
this ridge, along with a southward-sinking frontal boundary over
TX will provide forcing for an increase in rain chances beginning
Sunday. Initially low chances of rain (<20%) Sunday increase to
moderate (30-50%) by Labor Day as the boundary pushes south.
Sunday into early next week, most flooding concerns remain north
and east of our CWA. However, these showers and thunderstorms
through Tuesday carry the risk of gusty winds, locally heavy
rainfall, and lightning. By midweek as the frontal boundary washes
out, expect seasonal temperatures and a daily low chance (<30%)
of showers and thunderstorms along the sea breeze.

&&

.AVIATION...
(06Z TAFS)
Issued at 1220 AM CDT Fri Aug 29 2025

Light southeast winds and clear skies prevail across Deep South
Texas early this morning. Light southeast winds this morning will
become moderate (10 to 15 knots) with some gusts around 20 knots
this afternoon. VFR conditions will continue for the next 24 hours.

&&

.MARINE...
Issued at 1030 PM CDT Thu Aug 28 2025

Mid-level high pressure over central TX will allow for subsidence
and generally favorable marine conditions through Saturday. Expect
light (occasionally moderate in afternoon) south-southeasterly flow
and slight seas to prevail, before low rain chances (20%) return
Sunday. Moderate rain chances (40-50%) Monday and Tuesday as a
frontal boundary sinks southward across TX. Passage of this frontal
boundary will shift winds out of the north, before returning to
generally south-southeasterly by late next week.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             96  80  96  79 /   0   0   0   0
HARLINGEN               99  76  99  76 /   0   0   0   0
MCALLEN                103  80 102  79 /   0   0   0   0
RIO GRANDE CITY        104  77 104  77 /   0   0   0   0
SOUTH PADRE ISLAND      90  82  89  82 /   0   0   0   0
BAYVIEW/PORT ISABEL     95  78  94  79 /   0   0   0   0

&&

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

$$

SHORT TERM...69-HK
LONG TERM....69-HK
AVIATION...63-KC