Area Forecast Discussion
Issued by NWS Houston/Galveston, TX

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000
FXUS64 KHGX 240500
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1200 AM CDT Sun Mar 24 2024

...New AVIATION...

.SHORT TERM...
(This evening through Sunday Night)
Issued at 247 PM CDT Sat Mar 23 2024

Increasing moisture, along with the potential for some gusty
winds, continues to be the main story in the immediate term. An
eastward shift of broad surface high pressure over the SE CONUS,
along with the continued development of a lee cyclone to our NW,
will promote the development of a robust onshore flow pattern
overnight and into tomorrow. Winds have continued to shift to the
east throughout the course of the day today, and will veer further
southeastward overnight. Overnight lows will again dip into the
50s for most of the area, with values in the low 60s closer to the
coast. With the tightening surface pressure gradient as a result
of the aforementioned lee cyclogenesis, wind speeds will increase
substantially tomorrow. Sustained winds of around 20 mph, with
gusts occasionally in excess of 30 mph, will develop by tomorrow
afternoon. This will provide some steady moisture transport, with
dew points rising into the lower 60s by the evening. Temperatures
will be limited by increasing high cloud cover during the day,
with highs maxing out in the mid 70s. Further increases to cloud
cover will inhibit overnight cooling, which, combined with strong
WAA, will result in lows in the 60s area-wide.

In the early morning hours of Monday, an approaching prefrontal
trough ahead of the approach of a cold front extending from the
now mature lee cyclone (~984 mb) will potentially induce some
showers and storms across portions of the Brazos Valley. However,
the main rainfall threat associated with this system will not
arrive until Monday during the day (see below).

Cady

&&

.LONG TERM...
(Monday through next Friday)
Issued at 247 PM CDT Sat Mar 23 2024

The most interesting weather of the forecast period just so happens
to kickoff at the start of the long term period on Monday as a deep
layer trough moves in from the west on late Sunday night. This
induces southwesterly flow aloft, which is a favorable position to
get an influx of PVA. An upper level low embedded in this upper
trough over the Central Plains will drift northeastward towards the
Great Lakes Monday into Tuesday. The subsequent surface low will
follow a similar track and will drag a cold front through Southeast
Texas as it makes its northeastward journey across the central
CONUS. Moisture convergence along the prefrontal trough will raise
PW values to the 1.4-1.7" range late Monday morning/early afternoon
especially to the east of I-45. There`ll be plenty of shear to work
with as bulk shear (0-6km) stands at 70-80 kts with a 30-40 kt LLJ
overhead (stronger winds the further northeast you go). Large scale
ascent as a whole looks better over the Piney Woods as well.
However, instability looks to be a limiting factor, so the overall
severe threat will rely on everything lining up perfectly. As of
right now, the SPC has areas east of a Crockett-Coldspring-Anahuac
line in a slight risk of severe weather (level 2 out of 5) and areas
east of a College Station-Hempstead-Angleton in a marginal risk of
severe weather (level 1 out of 5) for Monday. Damaging winds will be
the primary hazard with any of the stronger storms, and this may be
one of those scenarios where storms are getting their act together
just as they exit the CWA to the east.

The showers and storms will accompany a prefrontal trough that
pushes through on late Monday morning/afternoon. This is out ahead
of the main cold front which pushes through on Monday night/early
Tuesday morning. Drier air filters in behind the front with PW
values around 0.5" by sunrise on Tuesday morning. This influx of
drier air will allow temperatures to cool into the upper 40s to mid
50s overnight on Monday. It`ll be ever so slightly cooler on Tuesday
with cooler 850mb temperatures sitting overhead. We`ll trade out
Monday`s highs in the low to mid 70s for a couple of days of highs
in the upper 60s to low 70s. Tuesday night looks to be the coldest
night of the period with temperatures dipping into the mid/upper 40s
north of I-10 and low 50s elsewhere (minus along the coast).

Things get a little bit interesting on Wednesday as a vort max on
the tail end of an upper level trough. It remains a bit questionable
on if there will be enough moisture for this to result in rain
showers...and even then there looks to be quite the pocket of dry
air above the surface (1.5-2 km). Looks like a virga scenario to me,
but in case some rogue sprinkles reach the surface, I included 15%
PoPs for the Brazos Valley on Wednesday afternoon. Nevertheless,
we`ll definitely see an increase in cloud cover on Wednesday. Once
the upper level trough exits to the east, it`ll be followed with
mid/upper level ridging. This takes us on a warming trend going into
the weekend with temperatures approaching the 80°F mark on Friday
and firmly in the low 80s over the weekend.

Batiste

&&

.AVIATION...
(06Z TAF Issuance)
Issued at 1200 AM CDT Sun Mar 24 2024

No major changes for latest TAF cycle. VFR conditions expected
to prevail through the period. Winds are variable with a generally
southerly component. Gusty conditions will develop shortly after
sunrise tomorrow morning. Sustained winds will increase to 15-20kts
with gusts as high as 30kts possible at times. Moderate to strong
onshore winds will bring an increase in moisture that will consequently
lead to an increase in cloud cover. CIGs should remain VFR, but some
locations could border or briefly touch MVFR later Sunday.  Adams

&&

.MARINE...
Issued at 247 PM CDT Sat Mar 23 2024

Northeasterly winds will continue to subside and transition to
become southeasterly by tonight. Onshore flow will gradually
strengthen ahead of the next approaching weather system which will
lead to a Small Craft Advisory going into effect on Sunday and
lasting into Monday afternoon. Winds will reach their peak on Sunday
afternoon into Monday with some gusts approaching gale force at
times. The elevated southeasterly winds will increase the risk of
rip currents along Gulf-facing beaches on Sunday and Monday.
Forecast trends are worth monitoring as there is some slight
indication that minor coastal flooding during high tide on early
Monday morning may be possible. The seas will respond accordingly
increasing to 8-10 feet Sunday night into Monday. Some showers and
thunderstorms will be possible on Monday as a cold front pushes
offshore. Light northerly winds will prevail in the wake of the
front into Tuesday as seas gradually subside. Seas may take until
Tuesday morning to fall below 7 feet in the offshore waters, so the
Small Craft Advisory will likely be extended. By Wednesday, winds
will transition to become northeasterly then become southeasterly by
late Thursday.

Batiste

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  62  73  48  67 /  30  80  10   0
Houston (IAH)  67  76  55  73 /  10  70  10   0
Galveston (GLS)  67  74  60  72 /   0  40  20   0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...Small Craft Should Exercise Caution from 7 AM CDT this morning
     through this afternoon for GMZ330-335-350-355.

     Small Craft Advisory from 4 PM this afternoon to 1 PM CDT Monday
     for GMZ330-335-350-355.

     Small Craft Advisory from 7 AM this morning to 1 PM CDT Monday
     for GMZ370-375.

&&

$$


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