190
FXUS64 KSHV 171803
AFDSHV

Area Forecast Discussion
National Weather Service Shreveport LA
103 PM CDT Fri May 17 2024

...New AVIATION...

.UPDATE...
Issued at 1152 AM CDT Fri May 17 2024

Our region remains largely free of convection late this morning,
and this is expected to continue this afternoon for most areas
with the exception of our northernmost zones and southeastern
zones weak forcing aloft is induced along the advancing trough
axis across the Middle Red River Valley and a southern stream
shortwave moving up the TX coast. Otherwise, expect partly to
mostly cloudy skies to continue and likely become more overcast
over the areas affected by convection. High temperatures should
generally range from the upper 70s to lower and middle 80s this
afternoon, and only minor changes were made based on current obs
and trends while accounting for the cloud cover and convective
coverage this afternoon. All updated text products reflecting
these changes have been issued.

/19/

&&

.SHORT TERM...
(Friday through Saturday)
Issued at 216 AM CDT Fri May 17 2024

The synoptic scale pattern around 08z this morning is
characterized by a split-flow pattern in the mid and upper levels,
with an enlongated trough of low pressure in the southern stream extending
from the Four Corners area eastward through the Southern Plains
and towards the TN Valley, with a belt of stronger W/NW flow and
lower amplitude troughing in the northern stream across the
Northern Plains and Upper MS Valley. Near the surface, several
weak boundaries are noted, one along the TX and LA Coasts and
extending east into the northern GOM, with another boundary across
OK and into the Midwest, with high pressure closer to the East
Coast.

Focusing in on the Four State Region, MRMS imagery depicts that
precip has exited to the south and east of the area, where much of
the severe storms and heavy rain moved across southern LA earlier
last evening. Although isolated showers cannot be ruled out
through daybreak, expect dry conditions to largely prevail, with
the development of patchy fog.

The local area will remain within SW flow aloft through the day
on Friday, with the main trough axis remaining to the west across
Northern TX/Southern OK. Despite this, several shorter-wave vort
maxes/perturbations will eject across the eastern flank of the
larger scale trough, one moving across AR and the other across
Southern LA. These shortwaves, combined with an unstable airmass
and some residual boundaries, especially across Southern Louisiana
will still prove sufficient for the development of showers and
thunderstorms this afternoon. Coverage will be nothing near what
was experienced on Thursday and the activity is largely expected
to remain sub-severe and pose no great threat for heavy rainfall
and flooding. For this reason, have opted to end the Flood Watch
for the area. Conditions today are still expected to remain mostly
cloudy, with some area experiencing some breaks in cloud cover.
Clouds should help temper high temps in the low to mid 80s.

The main axis of the larger scale upper level troughing will then
become more progressive late Friday evening into Friday night.
This will maintain low-end chances for showers and isolated
thunderstorms in the forecast into early Saturday morning. Along
with some residual shower activity early Saturday, conditions also
appear more favorable for areas of fog as winds remain light and
skies have the better ability to scatter some above a moist
surface. The trough axis will then be slow to shift east of the
forecast area on Saturday. With its continued presence over the
area on Saturday, very isolated showers and thunderstorms will
remain in the forecast, although most locations will experience
and dry and overall pleasant day with high temperatures creeping
into the mid to upper 80s as skies continue to scatter/clear.

Kovacik

&&

.LONG TERM...
(Saturday Night through Friday)
Issued at 216 AM CDT Fri May 17 2024

The larger scale upper level trough will finally begin to shift
east of the region Saturday night into Sunday, becoming gradually
replaced by an upper level ridge of high pressure. Fog will be
likely yet again Sunday morning under calm winds and clear skies.

The ridge of high pressure will maintain its influence over the
area through Monday and Tuesday, turning the main forecast concern
towards the return to hot and muggy conditions. Under sunny skies
on Monday, expect high temperatures to reach the low 90s. Tuesday
is likely to be a few degrees warmer, despite some low level
cloud cover in the morning, mainly across portions of W LA and E
TX. Dewpoints will be creeping into the low 70s by this time,
which will make for muggy conditions, however, the current
forecast does not support any heat related headlines.

By mid-week, the ensemble guidance is in fairly good agreement
with a trough moving across the Northern/Central Plains and into
the Upper MS Valley and helping to deamplify the ridge of high
pressure over the Southern US. As would be expected at this point
in the forecast period, it remain a bit unclear as to what degree
the ridge breaks down across the local area and how much/how
close any forcing from the trough is realized, but in general
guidance is supportive of a return of at least lower-end
rain/storm chances. Temperatures would be expected to cool a few
degrees if this pattern evolution were to verify, however, high
temps are still expected to hover around 90 degrees.

Kovacik

&&

.AVIATION...
(18Z TAFS)
Issued at 1242 PM CDT Fri May 17 2024

For the ArkLaTex terminals, low level circulation over SE OK with
the W/SW flow aloft buckling a weak upper level reflection as
well. And this may touch off some nearby showers or isold TS for
KTXK/KELD by early this evening with what heating remains until
about 03Z. Then some MVFR cigs toward daybreak and through mid
morning, but maybe not everywhere. We will be seeing VFR quicker
over the wknd by 15/16Z each day with heating building. Next
chance for convection will arrive late in the work week. /24/

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  83  69  86  68 /   0  10  10   0
MLU  82  67  83  66 /  20  20  20   0
DEQ  81  61  83  63 /  40  20  10   0
TXK  83  65  85  66 /  20  20  10   0
ELD  82  63  83  64 /  20  20  20   0
TYR  83  66  87  68 /   0  10  10   0
GGG  82  66  85  66 /   0  10  10   0
LFK  82  66  87  67 /  10  10  10   0

&&

.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&

$$

SHORT TERM...23
LONG TERM....23
AVIATION...24