Area Forecast Discussion
Issued by NWS Houston/Galveston, TX

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779
FXUS64 KHGX 142040
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
340 PM CDT Fri Jun 14 2024

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

.SHORT TERM...
(This evening through Saturday Night)
Issued at 258 PM CDT Fri Jun 14 2024

Relatively benign conditions will continue for the time being,
with warm and humid but nonetheless seasonable weather prevailing
in the immediate term. Surface high pressure over the SE CONUS and
a weak developing surface low in the Bay of Campeche will promote
a ESE surface flow, supplying relatively abundant moisture (total
PWs of ~1.5 in). Despite this, diurnal convection will continue
to be inhibited by the presence of a subsidence inversion at
~850mb, with only isolated chances of showers and storms expected
offshore through tomorrow night as a result. With winds becoming
light/calm overnight and dew point depressions remaining low,
some periods of patchy fog are possible between approximately
midnight and 7am. However, a prolonged dense fog event is not
expected.

Temperatures will once again rise into the mid 90s for inland
areas tomorrow, with the coast sitting near 90. Overnight lows for
both tonight and tomorrow night will remain mostly in the 70s
(near 80 along the immediate coast), aided by persistent WAA.
Daytime max heat index values will reach the triple digits for
most locations...while this does not represent an extreme heat
event, common heat safety actions like remaining hydrated when
outdoors will still be important.

Cady

&&

.LONG TERM...
(Sunday through next Thursday)
Issued at 258 PM CDT Fri Jun 14 2024

Sunday begins with ridging over the SE CONUS with a weak upper level
trough looming overhead. Highs are progged to reach the 90s during
the afternoon, with max heat indices reaching the triple digits area-
wide. This seems to be on-par with the typical Houston summer, with
ample moisture leading to humid and unpleasant afternoon conditions.
Notability this will be the warmest day in the long term forecast as
we transition into more of a wet pattern heading into the upcoming
week.

On Monday, a surface low is progged to spin up over the Rockies,
deepening later in the week as an upper trough digs in over the
Northwestern CONUS. With surface high pressure spanning the eastern
sea board, this should tighten the pressure gradient, increasing
onshore flow over the region. Combined with the upper trough
overhead, this will funnel humid Gulf air into SE Texas, creating a
corridor of deep moisture (+2" PWs) and numerous shortwave impulses
passing aloft. The end result will be wetter conditions with rounds
of showers/thunderstorms possible throughout the upcoming week.
Upper level forcing is largely lacking, since the aforementioned
trough axis cuts through most of SE Texas. Furthermore, models
suggest that this weak trough may initially steer most of the
shortwave impulses (and in turn some of the heavier storms) further
east of our area (towards Louisiana) early in the week. On a more
minor note, this early-week period may also see a weak plume of
Saharan Dust, which could further curb rain chances/totals [or at
the very least, create some hazy-white skies early Tuesday]. Either
way, another stronger burst of shortwave energy is progged to pass
over the coastal bend during the mid/late week as the upper trough
fills north. Despite those limiting factors, forecast soundings
throughout this period feature ample instability with saturated
conditions throughout the mid/lower levels, indicative of high
precipitation efficiency. Additionally, weak cloud layer winds and
weak Corfidi upshear winds suggest slower moving storms, which will
further amplify the potential for locally heavy rainfall.

With all those factors in consideration, WPC has a Marginal (level
1/4) Risk of excessive rainfall for Monday and Tuesday across the SE
Texas coast. The rainfall threat may likely extend into the later
half of the week as this humid Gulf airmass remains in place. Any
storms that develop during this period may be slower-moving in
nature, capable of producing locally heavy rainfall. The heavy
rainfall threat looks to be greatest closer to the coastline. Over
this 5 day period, rainfall totals in areas south of I-10 are
expected to range from 4-6 inches with isolated higher amounts
possible. Areas to the north will generally receive 1-3 inches.
during this same period. This rainfall will likely result in rises
in rivers, streams and creeks. The heavy rainfall threat currently
looks to be greatest on Wednesday/Thursday, especially so as soils
become saturated from prior rainfall and thus more prone to runoff.

This forecast will be further complicated by an area of low
pressure, which is currently anticipated to develop over the
Southwestern Gulf of Mexico/Bay of Campeche around mid next week.
Currently this system is expected to track west/northwesterly, with
recent model trends favoring a more westerly track that pushes the
low into Mexico late in the week. The presence of this system alone
should further tighten the pressure gradient, resulting in stronger
winds along the Texas coastal waters. The fully impacts of this
potential tropical system remain relatively uncertain at this time,
in part due to uncertainties in the forecast track and it`s northern
extent. This system could further exasperate the heavy rainfall
threat for mid/late next week, but it`s too early to make that call
yet. Stay tuned over the next several days as we monitor this
possible system.

03

&&

.AVIATION...
(18Z TAF Issuance)
Issued at 1251 PM CDT Fri Jun 14 2024

VFR conditions will generally prevail through the duration of the
TAF period. A few scattered clouds will continue to persist over
the course of the afternoon, but otherwise winds will remain light
and no cig development is expected. Overnight, winds become calm
with a few high clouds remaining over the area. Periods of patchy
fog are possible, which may at times result in a window of sub-VFR
visibility between approximately 08 and 15Z. Tomorrow, light to
moderate SE winds develop in the morning with conditions remaining
VFR.

Cady

&&

.MARINE...
Issued at 258 PM CDT Fri Jun 14 2024

Winds and seas will increase over the next several days as the
pressure gradient tightens while a long fetch sets up over the Gulf
of Mexico. Ample Gulf moisture will bring numerous showers/storms
daily, beginning on Sunday. Small Craft advisories could be needed
by early next week as winds approach 15 to 20 knots and seas reach 4
to 7 feet. These strong onshore winds over a long fetch will also
bring a high risk of rip currents across Gulf-facing beaches for
this upcoming week.

An area of low pressure is expected to develop over the Southwestern
Gulf of Mexico/Bay of Campeche by mid week. This system is currently
expected to track west to northwesterly into Mexico later in the
week. However, winds over the Texas coastline are still expected to
reach 20 to 25 knots by Wednesday with seas rising to 7 to 10 feet.
Winds and seas could possibly be higher depending on how this system
tracks.

03


&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  73  95  71  95 /   0   0   0  10
Houston (IAH)  75  95  74  93 /   0   0   0  20
Galveston (GLS)  81  90  82  89 /   0   0  10  30

&&

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

$$

SHORT TERM...Cady
LONG TERM....Cady
AVIATION...Cady
MARINE...03