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fxus64 kshv 212324 

Area forecast discussion
National Weather Service Shreveport la
624 PM CDT Thu Jun 21 2018

VFR conditions will prevail this evening, as few-broken VFR ceilings
become few-sky clear shortly after sunset. MVFR-IFR ceilings will make a
return overnight and have tried to insert best timing at each
terminal. In addition, could see MVFR fog affect ktyr and kggg.
Any lingering low clouds and fog will scour out by mid-late
morning tomorrow, and scattered-broken VFR ceilings will dominate the airspace
by tomorrow afternoon. Computer models hint at south-southwest
wind speeds increasing to around 10 kts sustained with gusts of
15-20 kts tomorrow afternoon at the majority of the terminals.
Furthermore, there is a chance for -shra/-tsra tomorrow morning
and afternoon,at ktxk and keld, and thus a prevailing -shra thunderstorms in the vicinity
has been inserted, with a thunderstorms in the vicinity inserted at kmlu. Will of course
amend as necessary.


Previous discussion... /issued 314 PM CDT Thu Jun 21 2018/

Short term.../tonight through Friday night/

Nwly flow aloft pinned between the ridge over the desert SW and a
closed upper low over the mid MS River Valley region will continue
to send impulses sewd across our region throughout the short-term
pd. Weak sfc boundary associated with the upper low to begin
migrating back nwd across our region overnight, becoming parallel
to the upper flow somewhere across the nrn third of our County Warning Area. Shwrs/tstms
will likely develop during the pre- dawn hours over these areas,
as the first of several impulses interacts with the front. However,
Friday aftn/evening, a secondary impulse will move across the
region, and, with ample daytime heating, may produce a few severe
storms capable of mainly damaging winds, large hail, and isold

As for temps in the short-term, overnight lows in the mid 70s
seems reasonable, as cloud cover is likely to affect at least some
portions of the region. Short-term blends indicate a much warmer
day for Friday than we've seen in the last several days. Have
modified this downward somewhat, as cloud cover/convection is
likely to inhibit heating at least a little, but still expecting
low to mid 90s just about everywhere. Higher humidities will also
result in heat index readings between 100 and 104 for much of the
region. /12/

Long term.../Saturday through Thursday/

An mesoscale convective system should be ongoing across ern OK/Arkansas Saturday morning, along
the primary upper level shortwave impulse that east into the mid-south.
Outflow bndrys may propagate east-southeast across extreme southeast OK and the nrn
portions of SW AR, but should encounter an increasingly drier low
level air mass farther S into NE Texas/north la such that have maintained
slight chance pops Saturday across the far nrn zones. Another in a
series of upper level impulses will again traverse the Red River
valley of srn OK and shift east into Arkansas Saturday night/Sunday, which
may build a little farther south-southeast into extreme NE Texas/srn AR, and thus
have maintained low chance pops north of the I-30 corridor, and slight
chance pops S to just north of I-20 in East Texas and across much of SW Arkansas.
But again, deep lyr drier air should restrict the swd development of
any convection, before these impulses shift east of the MS valley late
in the day.

Afterwards, upper level ridging will amplify north across the lower MS
valley and southeast Continental U.S. Monday and linger through much of the new work
week, resulting in very hot and dry conditions areawide through the
period. Temps should top out in the mid 90s areawide, but could
climb further as drying from the recent rains continue and erode
topsoil moisture. Could see a return of isolated convection across
the srn zones by the end of the week, which could be more seabreeze
induced (with the ern most position of the ridge per the gfs), or
via a weakness around the ern periphery of the ridge should it be
centered farther west over the Ozarks/srn plains (per the ecmwf). /15/


Preliminary point temps/pops...
shv 77 96 76 94 / 10 20 10 10
mlu 76 93 75 93 / 20 30 20 10
deq 71 93 74 93 / 20 40 30 20
txk 75 93 76 93 / 20 40 20 10
eld 75 92 74 93 / 20 40 30 10
tyr 76 96 76 94 / 10 20 10 10
ggg 77 95 76 94 / 10 20 10 10
lfk 76 95 76 95 / 10 20 10 10


Shv watches/warnings/advisories...

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