Area Forecast Discussion
Issued by NWS Shreveport, LA

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871
FXUS64 KSHV 100330
AFDSHV

Area Forecast Discussion
National Weather Service Shreveport LA
930 PM CST Sat Nov 9 2024

...New UPDATE...

.UPDATE...
Issued at 919 PM CST Sat Nov 9 2024

With the stalled surface boundary having retrograded slightly
westward this afternoon and evening, currently draped along a
north-south axis across east Texas, stubborn low cloud cover
looks to prevent overnight cooling more significantly than model
guidance initially targeted. Scattered clearing of skies may
manage to occur, but not over a widespread enough area nor long
enough duration to cool as much as initially projected.
Meanwhile, elevated dewpoint reinforced by ample tropical moisture
look to physically prevent much cooling. Using ShortBlend
guidance as a starting point, elevated lows to the mid to upper
60s east and middle 50s to lower 60s west. Otherwise, the
afternoon forecast package grids look to be on track. Ingested the
latest several hours of temperature and dew point obs, and
interpolated through to 15Z.

SP

&&

.SHORT TERM...
(This evening through Sunday Night)
Issued at 238 PM CST Sat Nov 9 2024

A dynamic heavy rainfall event is ongoing across north-central
Louisiana this afternoon as an axis of deeply rooted gulf moisture
along a stalled frontal boundary and lifting warm front, supported
by additional moisture availability from TC Rafael in the central
GoM, has resulted in a flash flood threat. Training showers and
thunderstorms are slowly moving across the SE zones of the SHV CWA,
and will continue to do so through the late afternoon and evening.
Present thinking is that on top of the general 2-4 inches that have
already fallen across the Flood Watch area, an additional 1-3 inches
are expected with locally higher amounts possible under the heaviest
reflectivity returns and rainfall rates. It is no surprise that this
scenario has evolved as it has given the perfect positioning of TC
Rafael for extra moisture propagation, while a stalled frontal axis
lingers across western Louisiana.

As mentioned, the heavy rainfall threat will continue into the
evening and likely the early stages of the overnight period before a
gradual weakening trend begins. Thinking is that the stalled
boundary will begin to move east as surface high pressure builds in
from the west. Hi-res solutions seem to be in pretty good agreement
that as the boundary moves east through the mid to late morning and
early afternoon of Sunday, a few showers and an isolated
thunderstorm or two may be possible. By the evening, the majority of
the CWA will be rain free, as the boundary works closer to the LA/MS
line.

Temperature forecast remains tricky, citing heavy cloud coverage,
frontal influence and PoPs. A range of 70`s to near 80 deg F will
be possible tomorrow after starting in the 50`s and 60`s during
the morning. With the passing front, much of the region should
see mid to upper 50`s heading into Monday morning.

KNAPP

&&

.LONG TERM...
(Monday through next Friday)
Issued at 238 PM CST Sat Nov 9 2024

When compared to the short term package, the long term appears
rather benign. That being said, still trending above average for
temperatures through the week as daily max temps approach the upper
70`s to near 80 deg F. Deterministic guidance looks to be coming
into more agreement synoptically through mid-week with upper ridging
moving across the southern CONUS ahead of troughing by Wednesday.
This will work to swing a cold front into the region once again,
with long range deterministic output across both the GFS and
ECMWF advertising the chance for showers and maybe a few
thunderstorms. Again, this is still deep into the forecast package
so monitoring trends in the coming days will help increase
confidence moving forward.

KNAPP

&&

.AVIATION...
(00Z TAFS)
Issued at 552 PM CST Sat Nov 9 2024

For the 10/00Z TAF period, IFR/LIFR cigs continue to plague most
of our terminals this evening with patchy fog and drizzle reducing
vsbys as well. Pockets of light to moderate rain will also impact
KMLU as a stationary boundary lingers across North Louisiana and
South Arkansas. Expect slow but gradual improvement in cigs/vsbys
during the latter half of the TAF period on Sunday with MVFR to
low VFR cigs by late morning through the afternoon hours. Light
and variable winds will be common overnight before trending more
NW on Sunday at around 5 kts or less.

/19/

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  67  78  59  77 /  20  20  10   0
MLU  67  78  60  76 /  80  40  20  10
DEQ  56  75  47  73 /   0   0   0   0
TXK  62  76  52  74 /  10  10   0   0
ELD  66  77  54  76 /  40  30  10   0
TYR  63  79  55  76 /   0   0   0   0
GGG  63  77  55  76 /   0   0   0   0
LFK  66  79  59  78 /  20  10   0   0

&&

.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...Flood Watch until 6 AM CST Sunday for LAZ013-014-018>022.

OK...None.
TX...None.
&&

$$

SHORT TERM...26
LONG TERM....53
AVIATION...19