543
FXUS64 KSHV 280220
AFDSHV

Area Forecast Discussion
National Weather Service Shreveport LA
920 PM CDT Thu Jun 27 2024

...New UPDATE...

.UPDATE...
Issued at 906 PM CDT Thu Jun 27 2024

A weak surface boundary across southeast Texas into west-central
Louisiana has allowed for scattered convection earlier this
evening. Convection has moved south and dissipated allowing for
dry conditions across the region. Stable conditions to persist
through the remainder of the overnight hours as surface high
pressure remains firmly established areawide. Under mostly clear
skies tonight, temperatures are forecast to radiate down into the
upper 60s to lower 70s across the ArkLaTex. However, temperatures
to climb into the mid to upper 90s on Friday with heat index
values forecast to exceed 105 degrees across most locations, with
the exception of possibly portions of southwest Arkansas.
Therefore, a Heat Advisory is in effect for locations with heat
index values forecast to exceed 105 degrees on Friday. Current
forecast is on track at this time, no update needed. /05/

&&

.SHORT TERM...
(This evening through Friday Night)
Issued at 312 PM CDT Thu Jun 27 2024

Cold front continues to advance south this afternoon, taking a
decent amount of time to exit the SHV CWA. Latest surface analysis
indicates the boundary slowly working across Toledo Bend, but
oriented just NW enough to still remain north of Lufkin, TX. As of
2:30 PM CDT, the LFK ASOS site reported a reading of 89/78,
indicating that the boundary still remains north of the obs site.
This boundary should work just south of the region this afternoon,
before stalling out after sunset. The front will then retreat back
north as a warm front Friday afternoon/evening.

Aloft, upper ridging will continue to build into the region this
evening, and overnight before completely influencing the local area
by Friday afternoon. Overnight temperatures will trend mild, with
lows by Friday morning ranging from the upper 60`s across the
north, to the low to mid 70`s across the central and southern zones.
As the aforementioned boundary advances back north tomorrow,
temperatures and dew points will begin to climb as maxT`s approach
the mid to upper 90`s, with area dew points returning into the low
to mid 70`s. As a result, heat index values will climb to at or
above 105 deg F, with some sites approaching as high as 110 deg F.
Given uncertainty in how quick the front will retreat back north
tomorrow afternoon, portions of SW Arkansas were left out of the
current Heat Advisory. If guidance continues to suggest a faster
northward advancing boundary, supporting heat indices to climb into
criteria for the counties left out of the present advisory, updates
will be needed either this evening or with the overnight package
to include those counties.

In terms of precip through the short-term package, supportive
thermodynamics will be mainly confined to the SE corner of the FA
where a few showers, and a thunderstorm or two will be possible
through the afternoon. Bulk of the afternoon diurnally driven
convection should remain south of the area.

RK

&&

.LONG TERM...
(Saturday through next Wednesday)
Issued at 312 PM CDT Thu Jun 27 2024

Long term story surrounds the return of heat under the influence
of upper ridging and humidity due to moisture return via surface
high pressure across the northern Gulf of Mexico. This will help
to reinforce southerly winds across the forecast zones, while
advecting a robust gulf airmass across the Ark-La-Tex, which in
return, will support an increase in area dew points. Given that
afternoon maxT`s will range somewhere in the upper 90`s on
Saturday and possible mid-70 deg F dew points, multiple areas of
the Four State Region could approach or briefly exceed heat index
values of 110 deg F. As a result, an upgrade to heat products may
be necessary if trends continue to point in this direction. If
not, heat advisory criteria will be met areawide through the
weekend, and the advisory will be extended.

Though heat remains the main headline with daily maxT`s in the mid
to upper 90`s, if not triple digits, rain chances will be non-zero
as a sfc boundary will attempt to back door into the FA Sunday
afternoon, and into Monday. For now, highest concentration of PoPs
exists across the eastern and northeast zones. This looks to be
the best shot for any widespread rainfall through the forecast
period as rain chances through the back half of the package will
be concentrated across the south and southeast zones given the
influence of seabreeze diurnally driven convection.

RK

&&

.AVIATION...
(00Z TAFS)
Issued at 627 PM CDT Thu Jun 27 2024

For the 28/00Z TAFs, generally VFR conditions look to continue
throughout the evening hours, with any lower CIGs in the form of
fair weather Cu fields. These clouds look to dissipate after
sundown, making for mostly clear skies overnight until the
development of patchy fog towards dawn. Keeping TEMPO groups for
terminals most likely to experience impacts. Any fog development
should burn off quickly, returning to VFR conditions areawide.
Winds will be light and variable overnight, becoming
southeasterly by daybreak.

/26/

&&

.PRELIMINARY POINT TEMPS/POPS...
SHV  76  98  80  99 /   0   0   0  10
MLU  72  96  77  97 /   0  10   0  10
DEQ  68  95  74  96 /   0   0   0   0
TXK  71  99  78  98 /   0   0   0   0
ELD  69  96  76  96 /   0   0   0  10
TYR  75  98  79  97 /   0   0   0   0
GGG  73  97  78  96 /   0   0   0  10
LFK  74  96  77  96 /   0  10   0  10

&&

.SHV WATCHES/WARNINGS/ADVISORIES...
AR...Heat Advisory from 11 AM to 7 PM CDT Friday for ARZ059-070>073.

LA...Heat Advisory from 11 AM to 7 PM CDT Friday for LAZ001>006-
     010>014-017>022.

OK...Heat Advisory from 11 AM to 7 PM CDT Friday for OKZ077.

TX...Heat Advisory from 11 AM to 7 PM CDT Friday for TXZ096-097-
     108>112-124>126-136>138-149>153-165>167.

&&

$$

SHORT TERM...05
LONG TERM....53
AVIATION...26