-- Discussion containing changed information from previous version are highlighted. --
177
FXUS64 KHGX 231135
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
635 AM CDT Mon Sep 23 2024

...New AVIATION...

.SHORT TERM...
(Today through Tuesday Night)
Issued at 339 AM CDT Mon Sep 23 2024

As the front approaches the CWA today from the west, low-level
onshore flow will continue to pull in moisture, resulting in PW
values increasing to around 1.6-2.0". As moisture converges along
the frontal boundary, isolated to scattered showers and
thunderstorms will develop. Rain chances will begin along the coast
this morning and will extend further inland as the day progresses.
The majority of activity is expected to remain south of I-10.

In addition to precipitation, low-level moisture combined with calm
winds will allow for the development of patchy fog for portions of
the Brazos Valley and Piney Woods area (mainly W of I-45) overnight
into Tuesday morning.

Fog development will depend on where the aforementioned frontal
boundary stalls out. Guidance continues to suggest stalling could
occur in the NE corner of SE Texas.

Similar weather pattern is in store for Tuesday as a mid-upper level
trough continues eastward, and interacts with an ample amount of
moisture still in place. Highest chance of rain will remain south of
I-10 and west of I-45.

Highs for today and Tuesday will be in the 90s for much of the area.
Locations along the coast and in the Piney Woods should see highs in
the upper 80s. Lows for tonight and Tuesday night will be in the
70s. Some locations in the Piney Woods may dip into the upper 60s
Tuesday night into Wednesday morning.

Adams

&&

.LONG TERM...
(Wednesday through next Sunday)
Issued at 1110 PM CDT Sun Sep 22 2024

Our pattern finally begins to change on Wednesday following a long
stretch of hot-and-humid weather as high pressure dominated over
Texas. An upper level trough digging down from the Northern Plains
will be entering the Lower Mississippi Valley on Wednesday, where it
will become a cutoff low and stall. PVA and moisture convergence
over coastal Texas will lead to increased showers and thunderstorms
activity on Wednesday (not just sea breeze activity), along with
increased cloud cover. The scattered showers and clouds will help
moderate daytime temperatures a bit, but WAA ahead of an approaching
cold front associated with the upper level low will lead to high
temperatures in the upper 80s to low 90s for much of the area. The
Piney Woods region may see the highest coverage of the afternoon
showers, so that are may not rise past the mid 80s. This
aforementioned cold front is expected to move through late Wednesday
into Thursday morning ushering in cooler, drier weather for Thursday.
Temperatures Wednesday night will be driven by the exact timing of
the FROPA, but we can expect low down into the mid to upper 60s for
much of the area, and then low 70s for the Houston Metro and along
the coast. Thursday is looking rather pleasant for our area with low
humidity and high temperatures generally in the mid 80s.

The upper level pattern gets a bit messy by the end of the week.
That closed low that stalls over the Mississippi Valley ends up
retrograding back westward Friday and into the weekend. This is due
to a tropical system (currently Invest 97L in the western Caribbean,
but likely a named tropical system by midweek) moving through the
eastern Gulf of Mexico effectively blocking the movement of the
upper level low. So, as this system moves back westward, so does the
moisture associated with it. The wrap around moisture may bring
scattered showers and storms to our area Friday into the weekend -
but confidence is not exactly high as it will be determined where
exactly the upper level low retrogrades to and how it interacts with
the tropical system. That upper level low ends up sticking around
through much of the weekend before finally moving off east late
Sunday into Monday. There will be a gradual increase in temperatures
Friday and through the weekend with highs back into the low to even
mid 90s by Sunday.

Fowler

&&

.AVIATION...
-- Changed Discussion --
(12Z TAF Issuance)
Issued at 632 AM CDT Mon Sep 23 2024

LIFR VSBYs and CIGs ongoing at LBX this morning. All other sites
at VFR. Fog may be possible over the next couple of hours at CXO.
All sites expected to be at VFR by late morning. SE winds around
10 kts expected this morning. SCT showers will develop along the
coast this morning and expand inland this afternoon. Have
continued with VCSH in the forecast; however, will need to monitor
for potential TSRA. Winds will become light and variable around
00Z
-- End Changed Discussion --

&&

.MARINE...
Issued at 1110 PM CDT Sun Sep 22 2024

Light to occasionally moderate onshore flow (5-10kt during the day,
then 10-15kt during the overnight and early morning hours) and low
seas (1-3ft) will continue through Tuesday. There will be increased
chances of scattered showers and isolated thunderstorms over the
coastal waters beginning through Tuesday as well. The winds
gradually back to the NE on Wednesday ahead of an approaching cold
front, and there will also be increased coverage of the showers and
storms on Wednesday. This cold front is expected to move through the
coastal waters late Wednesday night into Thursday bringing moderate
to strong northerly winds through Thursday night. Seas will likely
increase to 4 to 6 feet due to the increase in winds. Small Craft
Advisories may be needed.

Mariners should be advised that the NHC continues to monitor an area
of low pressure in the western Caribbean for tropical development
over the next several days. This system will gradually move
northwards and then northeastwards through the eastern Gulf of
Mexico through the end of the week. Little to no local impacts are
expected, but may see increased swells and increased risk of
strong rip currents by the end of the week.

Fowler

&&

.TROPICAL...
Issued at 1110 PM CDT Sun Sep 22 2024

The National Hurricane Center (NHC) has now designated the area of
low pressure in the western Caribbean as Invest 97L. Gradual
development of this system is expected over the next few days with a
Medium (50%) chance of development into a named tropical cyclone
within 2 days, and a High (80%) chance within the next 7 days. It is
expected to generally move northward across the eastern Gulf of
Mexico through the end of the week, and interests along the
northern and northeastern Gulf of Mexico should closely monitor the
forecast as conditions are favorable for development. Little to no
impacts are expected locally for SE Texas, but there will likely be
increased risk of strong rip currents by the second half of this
week. Please continue to monitor the latest forecasts and updates
from the NHC at www.hurricanes.gov.

Fowler

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  93  74  92  70 /  10  10  30  30
Houston (IAH)  93  76  93  75 /  20  10  50  30
Galveston (GLS)  87  79  87  76 /  20  10  40  30

&&

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

$$

SHORT TERM...Adams
LONG TERM....Fowler
AVIATION...Adams
MARINE...Fowler