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790
FXUS64 KHGX 251823
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
123 PM CDT Tue Aug 25 2026

...New SHORT TERM, LONG TERM, MARINE...

.KEY MESSAGES...

- Heat Advisory continues through Wednesday.

- Rain and storm chances increase slightly late Wednesday night
  and Thursday across the region.

- Low sea breeze storm chances continue through the weekend.

&&

.SHORT TERM...
(This evening through Wednesday Night)
Issued at 122 PM CDT Tue Aug 25 2026

Visible satellite imagery shows an expanding scattered cumulus
field across southeast TX indicative of the low level moisture in
place with some higher level cloud cover spreading in from the
north. This is associated with some decaying convection around the
eastern periphery of a stout mid level ridge over the Southern
Plains. The rest of the afternoon will generally be precipitation
free outside of an isolated (~10%) shower along the sea breeze.
Temperatures will top out in the upper 90s to 102 inland with mid
90s along the coast and heat indices between 105-110 degrees.

The center of the mid level ridge will begin a slow transition
westward over the next 48 hours with a weak disturbance evident
in water vapor imagery over southwest Kansas expected to spread
through the Southern Plains. This will likely result in another
round of convection well to our northwest overnight tonight. This
activity may be in the decaying phase again across our northern
counties early Wednesday morning with additional cloud cover
spreading into the Brazos Valley. Otherwise, Wednesday will be
similar to today with highs near 100 inland and heat index values
around 107-109 degrees. With northerly flow becoming a little
more pronounced around the eastern periphery of the ridge, a weak
front will begin to slide south across East Texas on Wednesday.
This will allow moisture to pool across the Brazos Valley late
Wednesday night where some low rain/storm chances will spread in
from the north after midnight.

Dunn

&&

.LONG TERM...
(Thursday through next Monday)
Issued at 122 PM CDT Tue Aug 25 2026

The aforementioned frontal boundary will sag southward into
southeast Texas on Thursday although it won`t be cooler by any
means. This will primarily be more of a wind shift although
moisture pooling along the boundary will be the main focus for
convective development in a weakly capped unstable afternoon
environment. Scattered showers and a few storms are expected
Thursday afternoon with coverage around 20-30%. Convective
coverage may be a little more robust across southwest Louisiana
during this time and we`ll have to see if this manages to spread
southwest late Thursday night into Friday particularly across the
coastal waters. With the expected increase in cloud cover and
potential for showers/storms, it`s likely that we`ll be able to
forego an extension of the Heat Advisory for Thursday, but that
temporarily relief will give way to more heat and humidity Friday
through the weekend as mid level ridging again builds back to the
east across the region. Highs will top out in the upper 90s each
day through Sunday with heat indices between 105-108 degrees.

Diurnally driven storm chances will likely tick upward again early
next week as a weak disturbance spreads across the northwest Gulf
into Texas with a slight reduction in afternoon highs.

Dunn

&&

.AVIATION...
(18Z TAF Issuance)
Issued at 1215 PM CDT Tue Aug 25 2026

VFR conditions will prevail across southeast Texas today with
partly cloudy skies and winds generally around 5 kts or less and
variable. Some MVFR-level cloudiness is expected to develop
overnight that could briefly constitute a ceiling, but most, if
not all, sites are expected to remain VFR overnight into Wednesday
morning. Light southerly winds are expected to shift to the
southwest by around 15Z and increase to the 5-10 kt range.

McNeel

&&

.MARINE...
Issued at 122 PM CDT Tue Aug 25 2026

Light southwest winds prevail across the coastal waters at this
time with southerly winds 10-15 kt expected tonight. Wind
direction will vary from southwest early in the day Wednesday and
Thursday to southerly 10-15 kt in the afternoons. Isolated showers
are expected this afternoon with storm chances increasing Thursday
afternoon into Friday. Otherwise seas 1 to 3 feet can be expected
with typical summertime diurnal wind direction changes through the
weekend.

Dunn

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  77 101  78 101 /   0   0  20  30
Houston (IAH)  79 100  80  98 /   0  10  10  20
Galveston (GLS)  83  90  82  90 /   0  10  10  20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Heat Advisory until 7 PM CDT Wednesday for TXZ163-164-176>179-
     195>200-210>214-226-227-235>238-300-313-335>338-436>439.

GM...None.

&&

$$

NWS HGX Office Area Forecast Discussion