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655
FXUS64 KHGX 220441
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1141 PM CDT Sat Sep 21 2024

...New LONG TERM, AVIATION, MARINE, TROPICAL...

.SHORT TERM...
(This evening through Sunday Night)
Issued at 217 PM CDT Sat Sep 21 2024

Upper level ridging remains in place overhead, resulting in another
hot and humid day. A few light showers will continue to develop near
the coast this afternoon, before tapering off by early this evening.
A quiet night is expected with patchy low-lying fog possible.

Conditions in Southeast TX will continue to be dominated by the
ridge aloft and at the surface on Sunday. Expect another hot and
humid day with highs in the 90s. Heights will gradually weaken as
mid/upper level ridge axis moves to our east and a cold front slides
southeast across the Plains. By Sunday evening/night....strong newly
persistent onshore flow should begin to push deeper Gulf moisture
into the region. Increasing moisture combined with a broad surge of
theta-e advection will lead to increasing rain/storm chances from
the coast overnight.

JM

&&

.LONG TERM...
-- Changed Discussion --
(Tuesday through next Saturday)
Issued at 1126 PM CDT Sat Sep 21 2024

The region will still be under the influence of an upper level
high pressure centered over the Gulf on Tuesday, so expect
continued summer-like weather with high temperatures in the low to
mid 90s for much of the area (the immediate coast will likely
stay in the upper 80s). There will be some isolated showers and
storms developing along the seabreeze in the afternoon, and the
rain from these storms will help cooler temperatures down a few
degrees locally. The upper-level pattern begins to change late
Tuesday into a Wednesday as a low pressure system drops down from
the Northern Plains, but there is still some uncertainty on how
this system evolves through the rest of the week. Both the GFS and
the EC transition the trough into a closed low by Thursday, but
the GFS does so over the Midwest and the EC does it over the
Southern Plains. Either solution will likely cause increased
moisture convergence over our area on Wednesday leading to greater
chances of showers and thunderstorms further inland (not just
along the sea breeze). Starting Thursday, the forecast gets a bit
more murky because if that upper level low ends up further east
over the Midwest, it will sweep a weak cold front through the area
ushering in cooler and drier conditions (and thus less rainfall
chances in our area). If that upper level low stays over the
Southern Plains, then we will stay a tad warmer (though cloud
cover will help limit some daytime heating) the moisture stays
with it leaving to increased chances of showers through the
remainder of the week. At this point, I am leaning more towards
the GFS/further east location of the closed low as it has been
fairly consistent with this solution over the past few days and
there might be a tropical system moving through the eastern Gulf
(more on this in the tropical section below) that will help "tug"
this upper level low further east.

Temperatures on Wednesday will be about 3 to 5 degrees cooler than
Tuesday with high temperatures in the mid to upper 80s and low 90s
for much of the area (the Piney Woods may stay in the low 80s due to
the scattered showers around). Low temperatures Wednesday night will
be in the mid 60s to low 70s for much of the area. There is a wide
spread in the potential high temperature on Thursday thanks to the
uncertainty of the passage of that cold front. The 90th percentile
of the NBM brings the temperatures into the low to mid 90s on
Thursday (the no front solution), while the 10th percentile keeps
temperatures in the low 80s (the progressive front solution). I
trended the forecast to the cooler side with the front, but not as
cold as the NBM10Pct, with high temperatures in the mid 80s for much
of the area. The low temperatures Thursday night has a similar
spread, but lows in the mid 60s to low 70s will be the most likely
solution with the FROPA. There will likely be a gradual warming
through the remainder of the week with temperatures rising a couple
of degrees each day. If the forecast trend moves more towards a
later/no front solution, then expect the temperatures to rise in
later forecasts.

Fowler
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&&

.AVIATION...
-- Changed Discussion --
(06Z TAF Issuance)
Issued at 1126 PM CDT Sat Sep 21 2024

VFR conditions will generally prevail overnight, with light and
variable winds continuing. A few instances of patchy fog may
reduce visibilities to below VFR levels just before sunrise, but
otherwise conditions should remain fairly benign. Tomorrow, a
light SE wind will develop with wind speeds generally remaining
below 10 knots. Cloud levels will remain around 2000 - 4000 ft.

Cady
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&&

.MARINE...
-- Changed Discussion --
Issued at 1126 PM CDT Sat Sep 21 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 midweek next week. There will be
increased chances of scattered showers and thunderstorms over the
coastal waters beginning Sunday night and continue through at least
midweek next week. A cold front may move through the coast waters on
Thursday bringing moderate to strong northerly winds, but the exact
timing is fairly uncertain at this time - or even if the front moves
through at all.

The NHC is monitoring an area of low pressure as it tracks through
the Caribbean and into the Southern Gulf by the middle of next week.
The NHC currently has a 70% (high) probability of formation over the
next 7 days. This system has not yet developed, so it is still far
too early to determine it`s track, intensity, or any specific
impacts from it - but mariners should continue to monitor forecast
updates for it from the NHC through the next several days.

Fowler
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&&

.TROPICAL...
-- Changed Discussion --
Issued at 1126 PM CDT Sat Sep 21 2024

The National Hurricane Center (NHC) continues to monitor the
northwestern Caribbean Sea and southern Gulf of Mexico as a broad
area of low pressure could develop by the early to middle part of
next week. Gradual development of this system is possible and could
strengthen as it moves into the Gulf of Mexico through the end of
next week. The NHC currently has a 70% (High) probability of
formation over the next 7 days. This system has not yet developed,
so it is still far too early to determine it`s track, intensity, or
any specific impacts from it. Don`t put too much stock into any
single deterministic model run. Please continue to monitor the
latest forecasts and updates from the NHC at www.hurricanes.gov.

Batiste/Fowler
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&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  73  94  73  93 /  10  10   0  10
Houston (IAH)  75  93  75  93 /  10  10   0  20
Galveston (GLS)  80  87  80  87 /   0  20  10  20

&&

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

$$

SHORT TERM...JM
LONG TERM....Fowler
AVIATION...Cady
MARINE...Fowler