478
FXUS62 KGSP 241743
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
143 PM EDT Mon Jun 24 2024

.SYNOPSIS...
High temperatures will peak on Wednesday ahead of a cold front
which will bring the next chance of showers and thunderstorms
to the area.  Hot and humid conditions will persist through the
weekend with a chance of showers and thunderstorms each afternoon.
Another cold front approaches the area late next weekend.

&&

.NEAR TERM /THROUGH TUESDAY/...
A llvl convg zone continues to cross the FA as noted by enhanced Cu
seen on the Vis Sat loops. Dont expect much if any chance of shower
develop as the subs inversion has become well defined and has
lowered to 5 Kft. Soundings show no chance of parcels making it past
this inversion, but if enuf sfc lift remains by max heating there
could a couple pop-up showers, which would be rather brief in
duration. A small-scale sfc high currently located over WV will
migrate southeast and off the Carolina coastline thru the period and
keep winds unfavorable for sfc-layered moisture transport, thus a
morning fog threat will be nil especially with the p/grad remaining
a little tight allowing for weak sfc mixing. On Tue, expect the
upper ridge to remain dominant and large scale subsidence negating a
precip/thunder threat. There will be elCAPE on the order of 1200 Jkg
available, but highly unlikely any of this will be realized with no
sigfnt triggers noted across the region. Lows tonight will remain a
couple degrees abv normal, while highs once again rise above normal
by 5-7 degrees within good insolation.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
Key Messages:

1) Lower Humidity and Dry Weather Continues Tuesday

2) Humidity Increases East of the Mountains Wednesday Ahead of an
Approaching Cold Front

3) This Front will also Increase Shower and Thunderstorm Chances
Wednesday Afternoon into Wednesday night

As of 200 AM Monday...Dry sfc high pressure will remain over the
region Tuesday into early Wednesday before a cold front tracks
across the western Carolinas Wednesday night. Lower humidity will
stick around on Tuesday before increasing on Wednesday as winds turn
SW`ly ahead of the approaching front. Highs on Tuesday should climb
into the low 90s in the mountain valleys and low to mid 90s east of
the mountains. Highs on Wednesday will be a few degrees warmer,
climbing back into the lower 90s in the mountain valleys and the mid
to upper 90s east of the mountains Wednesday afternoon. Thus,
temperatures will remain well above climo through the short term.
Heat indices should reach into the lower 100s in the Charlotte metro
and the Upper Savannah River Valley Wednesday afternoon but should
remain below Heat Advisory Criteria (Heat Advisory criteria begins
at a heat index of 105 degrees). Dry conditions will linger through
at least Wednesday morning before shower and thunderstorm chances
increase from west to east ahead of the FROPA Wednesday afternoon
into Wednesday evening. Convection will linger through the overnight
hours on Wednesday as the cold front tracks overhead. Capped PoPs to
chance (45% or less) area-wide Wednesday afternoon into Wednesday
night as global models still diverge on the exact timing/coverage of
convection. Guidance generally shows 20 kts or less of deep shear
and less than 2,000 J/kg of SBCAPE ahead of and along the cold front
Wednesday, so the severe potential looks to be low at this time.
However, if storms are able to develop ahead of the FROPA during
peak heating on Wednesday, a few isolated strong to severe storms
cannot be entirely ruled out (with the main hazard being damaging
wind gusts). The severe wx threat will be highly dependent on the
exact timing of the FROPA so confidence on the severe threat remains
low for now.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Key Messages:

1) Humidity Lingers East of the Mountains through the Long Term

2) A Cold Front Will Sink South of the Area Thursday into Friday
but Shower and Thunderstorm Chances Linger Behind the Front

3) Another Cold Front Will Track Across the Area on Sunday Keeping
Shower and Thunderstorm Chances Around

As of 230 AM Monday...Hot and humid conditions, as well as above
normal temps, stick around east of the mountains through the long
term period. A cold front will gradually sink south across the
eastern third of the forecast area early Thursday before pushing
into the Coastal Carolinas early Friday. With dry sfc high pressure
expected to remain just north of the Carolinas during this
timeframe, shower and thunderstorm chances will linger across the
area through the end of the workweek. Capped PoPs to chance (30% or
less) area-wide for now. Heat indices should once again climb into
the lower 100s each afternoon across the Charlotte metro and the
Upper Savannah River Valley, but look remain below Heat Advisory
Criteria for now.

Another large upper anticyclone will build over the southern US on
Saturday before gradually retrograding westward throughout Sunday.
At the sfc, a cold front will track across the Midwest on Saturday
before pushing across the western Carolinas on Sunday. This will
keep shower and thunderstorm chances around through the weekend.
Went with low-end chance PoPs (35% or less) on Saturday with higher
chance PoPs (45% or less) on Sunday for now. Humidity looks to
increase slightly this weekend which may allow for heat indices to
flirt near Heat Advisory Criteria each afternoon in the Upper
Savannah River Valley (Heat Advisory criteria begins at a heat index
of 105 degrees).

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
At KCLT and elsewhere: VFR flight conds will continue across all
sites thru the period. A sfc high center will migrate from West
Virgina to the Carolina coast which will veer winds outside the mtn
valleys from nw/ly to ne/ly or e/ly. Winds at KAVL will remain nw/ly
this evening and become channeled se/ly aft daybreak Tue. Winds
remain a little elevated overnight as a modest p/grad is maintained,
so dense fog will not be an issue except perhaps across the
sheltered mtn valleys of southwest NC.

Outlook: Widely scattered SHRA/TSRA may return as soon as Wed
aftn/evening, with seasonable summertime weather returning then and
continuing into the weekend.

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.

&&

$$

SYNOPSIS...AR
NEAR TERM...SBK
SHORT TERM...AR
LONG TERM...AR
AVIATION...SBK