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898
FXUS64 KHGX 232020
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
320 PM CDT Mon Sep 23 2024

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

.SHORT TERM...
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(This evening through Tuesday Night)
Issued at 320 PM CDT Mon Sep 23 2024

Seeing scattered showers this afternoon across the southwestern
half of the area where deeper moisture exists. An outflow boundary
originating from shower activity off to the NW shifted sfc winds
to N/NE across northern areas, but this boundary has stalled. Tonight,
a cool front will sag southeast into the area and this boundary may
provide a focus for some shower development overnight. Some patchy fog
is possible near and southeast of the front late tonight and early
tomorrow with light winds in place. Tomorrow, the frontal boundary will
likely become quasi-stationary across the area and will help focus
scattered showers and storms, especially during the afternoon hours.
Max temps tomorrow will be near 90, with partly to mostly cloudy skies.
Will see min temps a little cooler on Tuesday night across northern
areas which will be behind the front. Drier air will arrive after the
period on Wednesday as the front pushes further southeast.

Wood
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&&

.LONG TERM...
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(Wednesday through next Sunday)
Issued at 320 PM CDT Mon Sep 23 2024

What`s this yellow flag doing on the ground over here?! And is
that a referee?!

"False start to Fall...Southeast Texas...5 day penalty...repeat the
FROPA"

Ahh so it seems that the penalty for our false start to Fall earlier
this month is a 5 yard...I mean...5 day penalty for our first full
Fall-like day following the Autumnal Equinox (the start of the
astronomical season). That`ll be courtesy of a cold front that looks
to pass through generally in the late Wednesday/early Thursday
timeframe. The push for this cold front will be an upper level low
that cuts off from its parent trough (originally extends from the
Upper Midwest to the ARKLATEX). This upper level low will not only
be the driving force for the cold front, but it`ll also serve to
slingshot Potential Tropical Cyclone Nine (likely to become Helene
by Tuesday) into the northeastern Gulf Coast. We`re still not
expecting any direct impacts to Southeast Texas, but if you want
to read more about PTC Nine see the Tropical section down below.
There will be chances for scattered showers/storms along and ahead
of the frontal boundary, and prefrontal compressional heating
should allow us to squeeze out another day in the low 90s. On late
Wednesday/early Thursday, we have FROPA...and the details for
what`s behind that is so fantastic that it deserves its own
paragraph :)

By Thursday morning, PW values will be near the 10th percentile
(~0.88") and dew points will be down into the upper 50s/low 60s.
Now drier air still heats efficiently, but there`ll be cooler air
aloft thanks to the close proximity of the upper level low so
we`re only looking at high temperatures in the 80s Thursday and
Friday. Temperatures on Thursday/Friday night will be downright
pleasant with lows in the 60s. Double bonus, rain chances become
non-existent through the end of the work week with plenty of blue
skies to boot...but rain chances may come back over the weekend.

While there does look to be a general warming trend over the
weekend, it does come with a bit of uncertainty that all depends
on how quickly the upper level low ejects northeastward. If it
spends a longer period of time near the ARKLATEX, that keeps us
with cooler 850mb temperatures aloft. While it would still get
warmer, it`d be more of a small bump into the upper 80s/low 90s.
If it ejects northeastward quicker like the Canadian and 12Z Euro
are suggesting, then warmer 850mb temperatures would be able to
move in behind it and place us on the higher end of the
temperature guidance (mid 90s). All in all, we`ll have to see how
the upper level low interacts with the tropical system...but we
can at least plan on having a very pleasant end of the work week
that will actually feel like Fall. Some wraparound moisture could
attempt to reintroduce rain chances later in the weekend for areas
north of I-10, but this also depends on the placement of the upper
level low.

Batiste
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&&

.AVIATION...
(18Z TAF Issuance)
Issued at 1222 PM CDT Mon Sep 23 2024

Seeing scattered showers continuing across western and southeast
areas. Expect these to continue through the aft hours. Possible
to see a few TSRA mainly near SGR and HOU. Should lose most
convection this evening with the loss of heating. However, there
is a weak frontal boundary located across NW areas which could be
a focus from some isolated SHRA tonight. Tomorrow, expect
scattered showers areawide in the morning, a chance of TSRA across
the southeast half. Early tomorrow also expecting MVFR ceilings
at some sites, especially at CLL, UTS and CXO.

Wood/McNeel

&&

.MARINE...
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Issued at 320 PM CDT Mon Sep 23 2024

Light to occasionally moderate onshore flow and low seas will
continue into midweek. Daily chances for showers/storms also
persist ahead of an approaching cold front that will push through
the coastal waters on late Wednesday/early Thursday. By Wednesday,
winds will transition to northeasterly and likely will reach
caution flag criteria. Behind the front, expect increasing seas
and northeasterly winds that will likely necessitate Small Craft
Advisories. Elevated winds and seas should gradually subside by
Friday.

Mariners should continue to monitor the latest from the National
Hurricane Center on Potential Tropical Cyclone Nine (likely to
become Helene). This system is expected to intensify as it tracks
through the eastern Gulf of Mexico and towards the northeastern Gulf
Coast later this week. At this time, we are still expecting little
to no local impacts other than increased swells and an increased
risk for strong rip currents after midweek.

Batiste
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&&

.TROPICAL...
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Issued at 320 PM CDT Mon Sep 23 2024

The National Hurricane Center (NHC) is now issuing advisories on
Potential Tropical Cyclone Nine (likely to become Helene). This
disturbance is expected to strengthen and become a tropical storm
by Tuesday morning in the northwestern Caribbean Sea and a
hurricane by Wednesday morning as it enters the southern Gulf of
Mexico. All model/ensemble guidance continue to keep PTC Nine in
the eastern Gulf of Mexico and towards the northeastern Gulf
Coast/Florida Panhandle. At this time, we are still expecting
little to no local impacts for Southeast Texas other than
increased swells and an increased risk for strong rip currents
after midweek along Gulf- facing beaches. Please continue to
monitor the latest forecasts and updates from the NHC at
www.hurricanes.gov.

Batiste
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&&

.PRELIMINARY POINT TEMPS/POPS...
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College Station (CLL)  73  90  70  88 /  30  30  40  20
Houston (IAH)  76  92  74  90 /  20  40  30  30
Galveston (GLS)  79  88  77  87 /  10  30  20  40
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&&

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

$$

SHORT TERM...Wood
LONG TERM....Batiste
AVIATION...Wood/McNeel
MARINE...Batiste