-- Discussion containing changed information from previous version are highlighted. --
974
FXUS64 KSHV 290022
AFDSHV

Area Forecast Discussion
National Weather Service Shreveport LA
722 PM CDT Fri Jun 28 2024

...New UPDATE...

.UPDATE...
-- Changed Discussion --
Issued at 715 PM CDT Fri Jun 28 2024

Heat index values earlier this afternoon trended a little higher
than expected with several locations meeting or exceeding
Excessive Heat Warning criteria. Forecast progs for Saturday
suggest that the upper-ridge will be slightly stronger allowing
for afternoon high temperatures to potentially creep higher than
today, approaching 100 degrees in some locations. These hot
temperatures combined with dewpoint values in the mid 70s will
allow for heat index values to soar to 110 degrees across enough
locations to justify an Excessive Heat Warning areawide for
Saturday. /05/
-- End Changed Discussion --

&&

.SHORT TERM...
(This evening through Saturday Night)
Issued at 316 PM CDT Fri Jun 28 2024

The old residual sfc front that bisected the region this morning
has washed out this afternoon, with more humid air having returned
back N into Ern OK/SW AR this afternoon. In fact, coupled with
strong heating in the lower to mid 90s, heat indices have met
Advisory criteria this afternoon over much of the region,
including the Nrn sections of SW AR outside of the Advisory area.
The afternoon water vapor imagery indicates expansive flat
ridging aloft in place extending from SW TX E into the TN Valley
to the Gulf states, with a weak inverted trough noted over SE LA.
This trough has maintained isolated to widely scattered
convection over S LA this afternoon, with associated outflow
bndrys gradually spreading NE. Can`t rule out very isolated
convection possibly affecting the far Srn zones of Lower Toledo
Bend Country into Cntrl LA late this afternoon to around sunset,
but have maintained a dry forecast as what is left should quickly
diminish with the loss of heating. Given the return of higher
dewpoints in the more tropical air mass, min temps won`t fall much
below 80 tonight especially in the more urban areas, especially as
some wind may be maintained overnight.

The weak inverted trough aloft is expected to drift W just inland
of the LA coast tonight/Saturday, and again focus isolated to widely
scattered convection during the afternoon a little farther N into
portions of Deep E TX/Cntrl LA. Otherwise, even hotter temps are
expected with the flat ridging persisting overhead, with max temps
in the mid to upper 90s areawide. Coupled with the humidity, heat
indices will easily range from 105-110 degrees areawide, with some
isolated locales possibly exceeding 110 degrees. Given the current
heat indices in and outside the Advisory area this afternoon, and
reaching this threshold Saturday, have expanded the Advisory for
the Nrn sections of SW AR this afternoon, and extended it areawide
through 01Z Saturday. Limited cooling is expected Saturday night
with min temps near if not slightly falling below 80 degrees.

15

&&

.LONG TERM...
(Saturday night through next Thursday)
Issued at 316 PM CDT Fri Jun 28 2024

The progs are still in agreement with a weakness associated with
troughing from the Great Lakes Region SW into the Mid MS Valley
and the Ozarks Sunday drifting S along the Ern periphery of the
ridge center. This weakness aloft coupled with the strong
heating/instability and moisture in place should help focus
scattered convection especially in the afternoon, some of which
may slide SSE across SE OK/SW AR. Heat Advisory criteria should be
met Sunday over at least much of E TX/N LA/portions of far Srn AR,
but this will be determined as to the timing of convection
development and cloud cover early in the day. With the ridge
center building SE a bit more over the area Monday, isolated to
widely scattered convection will be focused more over N LA, before
the ridge expands farther E into the TN Valley and SE CONUS. Thus,
any convection will be more isolated Tuesday over the Srn zones
through the remainder of the first week of July, with the heat
building further with increased subsidence. Thus, the need for
heat headlines will continue through the remainder of the long
term period.

15

&&

.AVIATION...
(00Z TAFS)
Issued at 610 PM CDT Fri Jun 28 2024

VFR conditions prevail the 00z TAF package and are expected to
remain in place overnight across all terminals. Robust northward moisture
advection from the Gulf of Mexico will support an afternoon CU
field across area terminals, with a mix of SCT/BKN coverage below
10kft. Sea breeze push by the late afternoon may support VCTS
around the southern terminals, but confidence was not high enough
to include at this time.

RK

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  79  98  79  98 /   0  10   0  20
MLU  77  97  77  97 /   0  20  10  40
DEQ  74  95  76  94 /   0   0  10  40
TXK  79  98  79  97 /   0   0   0  30
ELD  75  97  76  95 /   0  10   0  40
TYR  80  97  78  97 /   0   0   0  10
GGG  78  97  78  96 /   0  10   0  20
LFK  77  96  75  96 /   0  20  10  20

&&

.SHV WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
AR...Excessive Heat Warning until 8 PM CDT Saturday for ARZ050-051-
     059>061-070>073.

LA...Excessive Heat Warning until 8 PM CDT Saturday for LAZ001>006-
     010>014-017>022.

OK...Excessive Heat Warning until 8 PM CDT Saturday for OKZ077.

TX...Excessive Heat Warning until 8 PM CDT Saturday for TXZ096-097-
     108>112-124>126-136>138-149>153-165>167.
-- End Changed Discussion --

&&

$$

SHORT TERM...05
LONG TERM....15
AVIATION...53