023
FXUS62 KGSP 230243
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1043 PM EDT Wed May 22 2024

.SYNOPSIS...
Temperatures will remain several degrees above normal each day
through Tuesday of next week as humid subtropical air remains
over the Southeast. Chances for showers and thunderstorms increase
Thursday and will remain higher than normal for this time of year
into next week as well.

&&

.NEAR TERM /THROUGH THURSDAY NIGHT/...
As of 10:15 PM EDT Wednesday: Over the past couple of hours, sct
showers and a few weak, embedded thunderstorms have made their way
over our northern NC mtns. This activity appears to be weakening
and based on the environment and the most recent CAM output, this
trend should continue as we head into the overnight. As such, the
rest of the overnight should be mostly dry with increasing cloud
cover, especially high clouds. Ripples of weak synoptic forcing
will move overhead during the predawn hours, but will encounter
air too dry to support much, if any, precipitation. The increasing
cloud cover should help to inhibit fog formation, including the mtn
valleys, thru daybreak, while keeping lows in the mid-60s, which
is about 4 to 6 degrees above climatology.

Otherwise, we can expect more convective activity for Thursday aftn/
evening. Despite the fact that flat upper ridging will remain to our
south thru the near-term period, heights will fall on Thursday as a
cold front sags into the upper Tennessee Valley/Cumberland Plateau.
Afternoon profiles look much more favorable for convection with an
influx of colder air aloft helping to increase lapse rates. This in
turn should allow for the development of roughly 1000 t0 1500 J/kg
of sbCAPE across much of our area and possibly more over the I-77
corridor. Shear values should remain fairly weak (ie, <30 kts of
deep-layer shear) and low-level helicity will be minimal at best
as well. Thus, strong to severe downburst winds appear to be the
main threat for tomorrow with hail being more of a secondary threat.
Thus, SPC`s current day 2 Marginal Severe Risk highlighting both
wind and hail still appears pretty well placed.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY/...
As of 215 PM Wed: A series of short waves will cross the area with
some sort of weak surface feature associated with the waves. This
will lead to mainly diurnal convection each day, with some lingering
showers possible during the overnight periods. Moderate instability
and bulk shear around 40 kts is possible on Friday, along with
decent sfc delta Theta-e values. A few severe storms will be
possible with some organization. With the good forcing in place,
expect widespread to numerous convective coverage of the mountains
and foothills and high end scattered coverage elsewhere. Temps will
be around 5 degrees above normal.

Coverage will not be as widespread on Saturday, but high end
moderate instability, along with 20 kts of shear and continued high
levels of sfc delta Theta-e values, along with increasing dCAPE may
lead to an uptick in severe thunderstorm chances. These would be
more of the pulse severe, damaging wind variety. Temps will be
around 10 degrees above normal.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 230 PM Wed: Unsettled weather expected into early next week as
the series of short waves continue to march across the area. Again,
there looks to be weak surface features until Monday when a more
organized cold front crosses the area. Expect precip chances to
steadily increase Sunday and Monday, although the convection should
be mainly diurnal. Some severe storms will be possible again
especially if the moderate instability and shear and dCAPE overlap.
Temps will be 5 to 10 degrees above normal.

Some lingering showers possible Tuesday even as the front moves
east, but thunder chances diminish. Temps will be up to 5 degrees
above normal. Dry high pressure expected on Wednesday with temps
near to slightly above normal.

&&

.AVIATION /03Z THURSDAY THROUGH MONDAY/...
At KCLT and elsewhere: Expect VFR conditions to continue thru
the 00z taf period. The only exception will be any restrictions
associated with convection that may impact terminals Thursday
aftn/evening. A broad area of sct to bkn cirrus will continue
to make its way eastward over the fcst area tonight ahead of
an advancing upper shortwave. Still expect the increased cloud
cover to hamper fog/low stratus development in the mtn valleys
such that KAVL should remain VFR thru the morning. Expect the
bulk of any thunderstorm activity to impact our area beginning
around 20z tomorrow afternoon with KAVL likely to see convective
activity a few hours sooner. For KCLT and the Upstate terminals,
I kept a PROB30 for the tstorm potential. Convective coverage for
KHKY and KAVL will likely be greater tomorrow, thus I use a com-
bination of prevailing TSRA and TEMPOs for TSRA for those sites.
Winds will remain S to SW thru the period, going light overnight
and picking back up tomorrow afternoon.

Outlook: Scattered to numerous showers and thunderstorms, along
with their associated flight restrictions, are expected again on
Friday. A more active pattern may persist thru early next week.

&&

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

&&

$$

SYNOPSIS...DEO
NEAR TERM...JPT
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...JPT