447
FXUS64 KSHV 012023
AFDSHV

Area Forecast Discussion
National Weather Service Shreveport LA
323 PM CDT Mon Jul 1 2024

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

.SHORT TERM...
(This evening through Tuesday Night)
Issued at 230 PM CDT Mon Jul 1 2024

The synoptic scale pattern this afternoon is characterized by a
longwave trough extending from the far NE Pacific southward into
the Desert SW and eastward into the Central and Northern Great
Plains, with a strong ridge of high pressure located downstream
across the Southern Great Plains and Deep South. Another trough is
noted across the NE Coast. In the lower levels, an expansive area
of high pressure extends across the Great Lakes and Midwest, with
its ridge influence pushing into the ArkLaTex and ArkLaMiss
regions, noted by a subtle cool frontal boundary.

Based on the analysis above, hot and humid conditions persist
across the Four State Region as subsidence aloft continues under
the strong H5 ridge mentioned above, keeping heat headlines in
place. The exception has been across most of Southwest Arkansas
where temperatures have remained "cooler" in the vicinity of the
backdoor cool frontal boundary. For the rest of this afternoon and
this evening, expect convection to continue to develop near and
ahead of the sfc frontal boundary, which will roughly range from
areas along a Texarkana to Shreveport to Jena line and westward as
MLCAPE values peak around 2000-3000J/kg wih dewpoints in the mid
to upper 70s. Thunderstorms will be single-cell in nature, with a
brief threat for small hail and gusty winds. Activity will
dissipate after sunset, yielding a partly cloudy and humid night
with low temperatures in the upper 70s to around 80.

For Tuesday, the sfc frontal boundary is expected to be draped
across western zones of the CWA before taking on a gradual retreat
northward and eventually either washing out or leaving evidence of
a very residual sfc trough. This may allow for convective
development again Tuesday afternoon as the overall lower level
airmass remains moist and unstable. With hardly any change in the
mid/upper level ridge, subsidence aloft will likely hinder overall
coverage. Temperatures are expected to be a few degrees warmer
than on Monday, resulting in the need for additional heat
headlines. Refer to the NPWSHV product for details on heat
headlines.

Kovacik

&&

.LONG TERM...
(Wednesday through next Sunday)
Issued at 230 PM CDT Mon Jul 1 2024

At the start of the long term period on Wednesday, a mid/upper
level ridge of high pressure will begin to amplify across the E
Pacific/Southern West Coast, with troughing downstream across the
Rockies and into the Plains. This will help push the persistant
ridge across the Deep South eastward towards the Southeast, with
sfc high pressure influence also beginning to shift east. Despite
this slight shift in the pattern, expect enough of a mid/upper
level ridge influence to keep the Four State Region hot and humid.
While isolated, diurnally driven convection cannot be entirely
ruled out, most locations will remain dry. Heat headlines will
likely again be needed.

By Thursday, the upper level ridge will continue to shift eastward
and dampen as troughing deepens across the Great Plains. While
Thursday will continue to remain hot and dry, by Friday a frontal
boundary will be approaching northern zone, bringing the chance
for some wider-spread rain and thunderstorms. Overall QPF amounts
do not look very impressive at this point in time, but it may
result in the best chance for locations to receive some rainfall
as compared to recent weeks.

Overall ensemble guidance is suggestive of a trough influence
continuing across the middle part of the country through the
weekend, which may allow the frontal system to continue to sink
south across the area. There will remain some uncertainty, of
course, this far out, as the pattern evolution across the middle
CONUS appears dependent upon the evolution of potentially high
amplitude ridge along the West Coast. For now, have at least
reflected a chance for widespread precip over the weekend, with
temperatures also a few degrees cooler than previous days.

Kovacik

&&

.AVIATION...
(18Z TAFS)
Issued at 1236 PM CDT Mon Jul 1 2024

Scattered showers and embedded thunderstorms have recently started
to form in a convergence zone running from north to south in East
TX, mainly along and south of I-20. Expect the coverage of at
least widely scattered showers and storms to increase over central
and western zones through the afternoon, potentially impacting
GGG, TYR, SHV, TXK, and LFK air spaces. Those latter areas have
VCTS in the TAFs through later this afternoon or early evening,
although TEMPO groups were included in GGG and LFK for early
through mid afternoon where potential for some impact is greater.
In general, expect storms to produce brief gusty and erratic winds
around or near their locations, although the potential for any
severe storms is quite low. Otherwise, ceilings will remain MVFR
for another hour or two in portions of the Arklamiss and could
potentially drop down that low in the middle of a thunderstorm
through the afternoon, but in general cu ceilings should range
from 3 to 6 kft. Expect convection to quickly dwindle this evening
with skies gradually clearing aside from residual high cirrus.
Very isolated patches of sub VFR visibilities or ceilings are
possible around and shortly after daybreak tomorrow, although the
potential for impacting any TAF site right now is too low to
include mention in the product. Winds at the surface will be
veering to the south tomorrow morning with convective coverage
likely very isolated tomorrow. /50/

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  80 100  82 100 /  20  20  20  10
MLU  73  98  78  98 /  10  10  10  20
DEQ  73  97  76  98 /  10   0   0   0
TXK  77  99  80 101 /  10   0   0  10
ELD  71  98  76  99 /   0   0   0  10
TYR  80 100  79  99 /  10  10  10   0
GGG  78  99  79  99 /  20  20  20   0
LFK  77  98  76  97 /  30  20  20  20

&&

.SHV WATCHES/WARNINGS/ADVISORIES...
AR...Heat Advisory until 8 PM CDT Tuesday for ARZ059-070.

LA...Heat Advisory until 8 PM CDT Tuesday for LAZ001>006-010>014-
     017>022.

OK...Heat Advisory until 8 PM CDT Tuesday for OKZ077.

TX...Heat Advisory until 8 PM CDT Tuesday for TXZ096-097-108>112-
     124>126-136>138-149>153-165>167.

&&

$$

SHORT TERM...23
LONG TERM....23
AVIATION...50