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428
FXUS64 KHGX 190312
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1012 PM CDT Sat Apr 18 2026

...New DISCUSSION, MARINE...

.KEY MESSAGES...

- Hazardous Marine Conditions: Moderate to strong northeasterly
  winds and building seas are expected overnight through Sunday
  evening following the frontal passage. Gusts to gale are
  expected.

- A Wind Advisory is in effect for the barrier islands through
  12pm Sunday.

- Seasonal conditions expected in the wake of a cold front going
  into early next week.

- Shower/storm chances return early next week with the potential
  for another round of locally heavy rainfall.&&

.DISCUSSION...
Issued at 1012 PM CDT Sat Apr 18 2026

Before we discuss the post-FROPA events, let`s do a quick summary of
the afternoon. Storms began to develop in the early afternoon hours
and did not have much propagation and moved over the same locations
for about an hour or two. Rainfall rates in these storms peaked in
the 4-6" per hour range, and with this falling right over the
Houston metro area...it led to some issues to say the least.
Multiple reports of street flooding came in mainly east of I-45
inside the 610 loop, and even a portion of I-10 was completely
shutdown for a period of time due to flooding. Max rainfall
totals were just over 3.5" along Buffalo Bayou east of downtown.
This is the second weekend in a row with flooding in Harris
County...and the second weekend in a row where I`ve been on shift
for flooding in Harris County. I think the saying goes that twice
is a coincidence!

Scattered showers and (elevated) isolated thunderstorms will persist
into early Sunday morning, which is when the 850mb front pushes
through and ushers in drier air. It`s not entirely out of the
question for small hail development with some of the elevated
convection this evening/overnight. PW values remain above the 90th
percentile (~1.57") overnight, so locally heavy rainfall cannot be
completely ruled out. The latest CAMs show the potential for another
0.5-2.0" of rain tonight into early Sunday morning, so we`ll
continue to monitor trends/radar overnight. Temperatures overnight
will bottom out mostly in the 50s. In addition to the lingering
rain, gusty northeasterly winds will prevail in the wake of the
front overnight through Sunday morning. As a result, a Wind Advisory
has been issued for the barrier islands through 12pm Sunday. Sunday
will be breezy and seasonal with sunshine gradually becoming more
prevalent throughout the day as that drier air filters in. Expect
high temperatures to top out in the low to mid 70s. Low temperatures
on Sunday night will range from the upper 40s to the upper 50s.

Our attention then turns to Monday. The 850mb high remains overhead
leading to either the same or slightly cooler daytime high
temperatures. Surface high pressure kicks out to the east Monday
morning allowing for moisture to return rather quickly especially
west of I-45. As an embedded shortwave pushes into the region, a
coastal low/trough develops along the South TX coast and gradually
pushes northeastward towards the Upper TX coast going into Tuesday.
PW values will at least be near the 90th percentile, so locally
heavy rainfall will be possible. As a result, WPC has already
outlined areas generally along and west of I-45 in a marginal risk
(level 1 of 4) of excessive rainfall on Tuesday.

Rain chances remain elevated into Wednesday. Diurnal isolated to
scattered afternoon convection possible towards the end of the work
week. Expect a gradual warming trend throughout the work week as
ridging aloft builds in. Another upper level low moves through the
CONUS towards the end of the work week though, which brings our next
notable chance of showers/storms going into next weekend.

Batiste

&&

.AVIATION...
(00Z TAF Issuance)
Issued at 615 PM CDT Sat Apr 18 2026

The anticipated cold front has swept through all by LBX and GLS,
which it will be doing within the next hour or two. While the
front will have pushed off the coast, lingering moisture will lead
to scattered showers (and even an isolated thunderstorm) through
late tonight before ending north to south. Some isolated showers
may linger near GLS through sunrise.

MVFR conditions will prevail through the night with CIGs around
1500-2000ft and some scattered lower clouds. The clouds will
scatter out through the early morning hours giving way to VFR
conditions that will persist through Sunday.

The cold front has ushered in strong north-northeasterly winds
with sustained winds of 15-20kt and gusts to 25-30kt. These winds
will persist through Sunday morning, then slowly lower and veer
through the day on Sunday. Winds will be strongest near the coast
impacting GLS.

Fowler

&&

.MARINE...
Issued at 1012 PM CDT Sat Apr 18 2026

Scattered showers and isolated thunderstorms will persist going into
Sunday morning before drier air filters in. The cold front has begun
to push offshore, so expect strong northeasterly winds to prevail in
the wake of the front going into Sunday afternoon. Expect sustained
winds in the 20-30 kt range with frequent gusts to gale (35-40 kt)
especially in the southern parts of the bays and the Gulf waters
overnight into early Sunday morning. As a result, a Gale Warning is
in effect for the Gulf waters through early Sunday afternoon. This
will be followed by a Small Craft Advisory through Sunday evening. A
Small Craft Advisory is in effect for the bays through Sunday
afternoon, but keep in mind that gusts to gale are possible through
early Sunday morning. These strong winds will lead to very rough bay
waters and seas peaking in the 7-10 ft range in the Gulf waters.
Seas may occasionally be higher, especially overnight into Sunday
morning.

Winds transition to easterly on Monday then southeasterly by Monday
night as chances for showers/storms increase with another upper
level disturbance approaching. Water levels are expected to remain
around 3.0 feet above Mean Lower Low Water during high tide cycles
going into early next week.

Batiste

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  51  74  54  69 /  50   0  10  20
Houston (IAH)  56  73  57  72 /  70  10   0  20
Galveston (GLS)  60  73  67  74 /  80  30  10  20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Wind Advisory until noon CDT Sunday for TXZ436>439.

GM...Small Craft Advisory until 1 PM CDT Sunday for GMZ330-335.

     Gale Warning until 1 PM CDT Sunday for GMZ350-355-370-375.

&&

$$

DISCUSSION...Batiste
AVIATION...Fowler
MARINE...Batiste

NWS HGX Office Area Forecast Discussion