862
FXUS62 KGSP 090612
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
212 AM EDT Thu May 9 2024

.SYNOPSIS...
Widespread shower and thunderstorm activity will continue through
this morning, with severe storms expected. The cold front will push
east Thursday night into early Friday morning allowing for drier
conditions. Another system approaching out of the south may bring
shower and thunderstorm chances back to the region on Friday. Drier
conditions and below normal temperatures return for the weekend.

&&

.NEAR TERM /THROUGH TODAY/...
As of 145 AM EDT Thursday: The Tornado Watch was expanded east to
include the rest of the SC Upstate and remains in effect through 4AM
EDT. A strong line of showers and thunderstorms continues pushing
southeastward across the forecast area this morning. Severe storms
are mainly noted along the southern portion of the line (NE GA and
SC Upstate), with strong storms noted over the northern portion of
the line (NC Piedmont). The main hazards with any severe storms will
be damaging wind gusts, large hail, and isolated tornadoes. A few
Flood Advisories were also issued this morning due to the heavy
rainfall associated with these storms. Increased of PoPs and PoTs to
account for widespread thunderstorm activity this morning, otherwise
no major changes were needed.

The air mass east of the Blue Ridge for the most part did not
recover from this afternoon, and now only shows >500 J/kg at best,
which will keep most of the activity in check. The main concern is
the area from the SW mountains down across northeast GA and the
Savannah River basin. However, enough effective shear and low level
shear remain in place, allowing storms to maintain supercell
characteristics. All threats are in play across this area, so SPC
issued a Tornado Watch across NE GA and the SC Upstate. This
activity will traverse the fcst area thru the early morning hours.
Based PoPs off the HRRR as the model has had a good and consistent
handle on activity the few several hours. Another round of showers
and thunderstorms may come in behind this one, but the severity will
be even more restricted toward daybreak as the atmosphere will
likely be worked over.

Otherwise...for Thursday...not quite as warm but still mid 80s in
the Piedmont. Slight Risk in place on Thursday but that`s as the
convection slips south in the morning.

&&

.SHORT TERM /TONIGHT THROUGH SATURDAY/...
As of 100 PM EDT Wednesday: For the Thursday night period, the 12z
HREF and CAM consensus depicts just very limited and isolated deep
convection lingering from whatever daytime activity redevelops,
along with a smattering, but again limited response into the night
and mainly confined to the mountains.  Not unexpectedly, the pattern
atop the SE CONUS remains dynamic into Friday as energy rounding the
base of the upper trough will finally be again to shove lingering
sfc frontal zone downstream of the cwfa.  But before it does, we
will be wary for the threat for tstm encroachment and redevelopment,
along the front itself, and in addition, MCS/bowing cluster moving
in from Georgia.  Sensible weather will feature a shotgun mid-chance
pop for Friday with isolated svr storms possible mainly SE of I-85.
Will plan on overspreading the region with deep layered dry air
within the broad downward vertical motion behind the departing s/wv
axis Friday night.  Expecting to be under a well mixed and more
seasonable airmass within the deep cyclonic flow on Saturday
featuring maximum temperatures close to climo.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 1252 am EDT Thursday: The rest of the upcoming weekend
looks like it should be quiet, with a mid/upper ridge axis to our
west supporting weak sfc high pressure on Sunday. Temps should
be right around normal into Monday. The ridge axis moves overhead
early Monday and then things start to go downhill. The next system
moving over the Plains on Monday will begin to spread moisture back
in from the southwest by late in the day, although the models do
not agree on when precip might develop up from the southwest. Be
that as it may, the pattern favors a quick moisture return with
sfc high pressure off the Mid-Atlantic coast, so if precip doesn`t
develop by sunset on Monday, it will overnight. The rest of the
early half of the week look busy again as the upper system slowly
approaches then moves past Tuesday night and into Wednesday. Precip
probs climb up into the Likely range, but we have removed the
categorical for the time being. Temps will stay on the cool side
on Tuesday owing to extensive cloudiness and precip. We should
get another brief break in the action in the wake of this system,
probably on Wednesday, but afterward we remain in a busy looking
part of the flow with perhaps another upper feature moving in by
the end of the period. Temps could pop back up about five degrees
above normal on Thursday, but there is much uncertainty.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
At KCLT and elsewhere: Widespread SHRA and TSRA are tracking over
the terminals this morning leading to mainly LIFR to MVFR
restrictions. With the strongest activity expected to continue
through the next few hours, went with TEMPOs for TSRA from 06Z-10Z
for all terminals. Strong, gusty winds can be expected within
stronger thunderstorms. From 10Z-15Z have SHRA with a PROB30 for
TSRA as thunder should become more isolated once the main line of
activity pushes east. Should see drier conditions develop by the
late morning to early afternoon, which should allow restrictions to
lift across the terminals. Wind direction will generally be variable
through daybreak with shower and thunderstorm activity around, but
should eventually pick up out of the SW around sunrise. Winds will
remain SW through this afternoon before turning WNW across the mtns
and WSW east of the mtns this evening into tonight. Low-end gusts
are expected to develop this afternoon as a cold front track over
the western Carolinas. Dry conditions should linger through tonight.

Outlook: A system lifting out of the south my increase shower
and thunderstorm chances again on Friday, but confidence on this
remains low. Drier conditions can be expected this weekend.

&&

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

&&

$$

SYNOPSIS...AR
NEAR TERM...AR/PM
SHORT TERM...CSH
LONG TERM...CSH
AVIATION...AR