707
FXUS64 KSHV 261827
AFDSHV

Area Forecast Discussion
National Weather Service Shreveport LA
127 PM CDT Wed Jun 26 2024

...New AVIATION...

.UPDATE...
Issued at 1141 AM CDT Wed Jun 26 2024

Quite a few changes needed to the forecast this morning, as an
expansive MCS that originated over NE OK/SW MO/NW AR early this
morning that intensified some as it has tapped diurnal heating
across extreme SE OK/Wrn AR. Only the HRRR has initialized well on
the current convection, as the other hi-res progs are much too
slow with the convection development and its spread through the
region late this morning through the afternoon. This convection
has largely been driven along a weak shortwave trough sliding SE
along the Ern periphery of the upper ridging centered over Srn NM
just W of ELP, in an area of slightly stronger 0-6km shear of
30-40kts. The latest mesoanalysis depicts the shear dropping off
farther S into NE TX/Srn AR (but a bit stronger along its Wrn
flank over NCntrl TX), although it is encountering stronger
heating and dewpoints in the mid/upper 70s which has resulted in
SBCapes of 3000-3500 J/kg. Thus, the HRRR`s solution in
maintaining convection as it shifts S through the region this
afternoon seems justified, with the potential for strong to at
time severe convection possible with damaging winds the primary
threat.

Have updated the forecast to increase pops significantly to likely
over much of the region, with high chance pops across the Srn
sections of Deep E TX into Cntrl LA. This MCS has also generated a
strong cold pool in its wake, with temps having fallen into the
upper 60s/lower 70s, which should translate S through the
area during the afternoon. Thus, have cancelled the Heat Advisory
for Red River County Texas, McCurtain County OK, and the northern
sections of SW AR as these storms currently or shortly bear down
over these areas. Farther S, very limited mixing and strong
heating should result in at least a brief period of enhanced Heat
Risk before the storms arrive, with heat indices ranging from
105-109 degrees. Have left the Advisory as is elsewhere although
this will likely be trimmed back/cancelled early with the passage
of the convection.

Have also lowered max temps across the Nrn zones this afternoon,
although some recovery is expected once the rains end by early
afternoon. Did lower temps a tad even farther S, given the
imminent arrival of the convection, as well as the extensive
stratocu cigs along/S of I-20.

Thank you WFO LZK for coordination this morning. Zone update
already out...grids will be available shortly.

15

&&

.LONG TERM...
(Thursday Night through Wednesday)
Issued at 356 AM CDT Wed Jun 26 2024

Drier conditions will return Friday and Saturday, as the center of
the upper ridge moves back over the region. Additional heat
products will be likely, as afternoon highs will return into the
mid 90s to around 100 degrees.

Upper ridging will remain in place on Sunday and Monday, but the
center of the ridge will slide westward over North Texas. Long
range models are suggesting there could be enough weakness over
the region for some widespread convection to develop with daytime
heating. But, these chances look to diminish as we move into the
middle portions of next week, as the center of the ridge shifts
back over the region. Despite the rain chances, it still looks
like hot and humid conditions will continue. Additional heat
products will be likely with afternoon highs remaining in the mid
90s to near 100 degrees.

&&

.AVIATION...
(18Z TAFS)
Issued at 104 PM CDT Wed Jun 26 2024

For the ArkLaTex terminals, near Squall line affecting I-30
earlier is now moving into our I-20 corridor with N-NW wind gusts
to around 50-55KT expected with heavy rainfall dropping the vsby
to less than a mile for a bit. Computer models are content with
this one and done as a weak cool front sags across the Natural
State. We may see some light BR around daybreak as skies become
fair this evening. Some indication of MVFR cigs too, 09-15Z. /24/

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  96  77  95  78 /  60  40  20  10
MLU  97  73  92  74 /  60  50  30   0
DEQ  92  73  93  72 /  80  30  10   0
TXK  95  75  95  76 /  60  40  10   0
ELD  94  71  91  72 /  60  30  10   0
TYR  95  77  97  78 /  40  30  10   0
GGG  95  76  95  77 /  60  30  10   0
LFK  96  77  95  76 /  40  30  20   0

&&

.SHV WATCHES/WARNINGS/ADVISORIES...
AR...Heat Advisory until 7 PM CDT this evening for ARZ070>073.

LA...Heat Advisory until 7 PM CDT this evening for LAZ001>006-010>014-
     017>022.

OK...None.
TX...Heat Advisory until 7 PM CDT this evening for TXZ097-108>112-
     124>126-136>138-149>153-165>167.

&&

$$

SHORT TERM...15
LONG TERM....20
AVIATION...24