633
FXUS64 KHGX 301105
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
Issued by National Weather Service Corpus Christi TX
605 AM CDT Wed Apr 30 2025

...New AVIATION...

.SHORT TERM...
(Today through Thursday Night)
Issued at 233 AM CDT Wed Apr 30 2025

Today will be more active weather-wise, courtesy of a mid/upper
level trough pushing east across the Southern Plains/Desert
Southwest. Deep moisture coinciding with a 20-30 knot LLJ over the
area should initially bring some WAA showers over our western
counties, spreading eastward throughout the day. Isolated
thunderstorms become more feasible throughout the afternoon as we
reach peak heating, though short-range model guidance has trended
toward lower activity during this afternoon period. Still, this
environment features ample instability with SFC CAPE around 2000-
2700 J/KG and CIN values over -10 J/KG. 0-6km wind shear around 30-
40 knots should provide sufficient organization necessary to produce
stronger storms. Forecast soundings indicate higher precipitation
efficiency as we often see here in SE Texas, suggesting the
potential for stronger downpours. While instability will wane this
evening, high-resolution models continue to show a stronger, more
organized line of thunderstorms reaching SE Texas not long after
midnight, reaching as far south as Galveston Bay before dissipating
Thursday morning. The HRRR continues to depict a more potent
solution compared to other model guidance, though notably it was
first to pick up on this organized line yesterday, with rather
consistent outputs between model runs.

For both today and Thursday, SPC has a Marginal to Slight Risk
(levels 1/5 to 2/5) of severe weather, with WPC placing a Marginal
to Slight Risk (levels 1/4 to 2/4) of excessive rainfall over much
of the same area, especially further north over the Brazos
Valley/Piney Wood area. All severe/rainfall hazards are on the table
for today through this evening, with damaging winds and locally
heavy rainfall becoming the primary concerns overnight into Thursday
as the convective line pushes south.

There should be a lull in rainfall from the mid morning to the early
afternoon on Thursday with another round of showers/storms from the
late afternoon through late Thursday night. Much of this activity
should be concentrated north of the I-10 corridor. The risk of
severe weather & excessive rainfall should be trending downwards
throughout this time frame as the aforementioned trough departs to
the northeast.

03

&&

.LONG TERM...
(Friday through next Tuesday)
Issued at 1145 PM CDT Tue Apr 29 2025

Shower and thunderstorm chances will increase as we head through
the day Friday and Friday night as a weak frontal boundary sags
into the area and serves as a llvl focusing mechanism. This
boundary will probably make it somewhere close to the coast early
Saturday morning then stall as the push of high pressure behind it
moves off to the east versus south. Locations north of the
boundary will see a brief period of cooler & drier wx for the
first part of the day Sat, but deeper moisture pooling to its
south will begin lifting again as the day wears on. Combined with
a somewhat messy quasi-zonal flow, would anticipate the
possibility of additional scattered precip to re-develop inland
later in the day.

The next West Coast trof will track across CA and toward the Four
Corners area Sun-Tue. We`ll see some mid level ridging take shape
locally in advance which should generally lead to to warmer
conditions and lower chances of rainfall.

47

&&

.AVIATION...
(12Z TAF Issuance)
Issued at 542 AM CDT Wed Apr 30 2025

MVFR CIGS/Cloud Decks are currently in place across much of SE
Texas with light showers filling inland from the coast. Expect
broader improvements in CIGS later this morning after sunrise
while gusty S/SE winds set in with VFR conditions returning this
afternoon. Isolated thunderstorms, some strong to severe, could
develop over portions of SE Texas during the afternoon. A brief
lull in showers/storm activity is possible during the late
afternoon/early evening as daytime heating wanes. A convective
line of thunderstorms should push into southeast Texas late
tonight through early Thursday morning. Storms along this line may
also become strong to severe at times. MVFR CIGS are expected to
fill in across the region again during this overnight period.

03

&&

.MARINE...
Issued at 1145 PM CDT Tue Apr 29 2025

A somewhat tight pressure gradient between high pressure to our
east and lower pressure to our west will lead to moderate onshore
winds, 4-7ft seas and above normal tides through midweek. Expect
periods of caution flag and/or advisory level conditions with
speeds lingering around 20kt +/-5kt into Wed night-Thurs. There
will be a high risk of rip currents along area beaches. Water
levels will also be running above normal, but generally peak below
levels typically seen with coastal flood concerns. Chances for
showers and storms return later Friday into Saturday as a weak
front sags toward the coast.

47

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  82  68  87  69 /  40  70  20  20
Houston (IAH)  83  71  86  71 /  40  70  40  10
Galveston (GLS)  81  75  81  75 /  10  10  20  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Beach Hazards Statement through this evening for TXZ436>439.

GM...Small Craft Advisory until 1 PM CDT this afternoon for GMZ330-
     335-350-355-370-375.

&&

$$

SHORT TERM...03
LONG TERM....47
AVIATION...03
MARINE...47

NWS HGX Office Area Forecast Discussion