589
FXUS62 KGSP 270217
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1017 PM EDT Sun May 26 2024

.SYNOPSIS...
Temperatures remain above normal through Monday.  There is a risk of
strong to severe thunderstorms from this evening until the cold
front passes Monday evening.  Cooler and drier conditions return
tuesday through Friday.

&&

.NEAR TERM /THROUGH MONDAY/...
As of 1002 PM EDT Sunday: A very busy evening is finally starting to
wind down as the last bit of lingering convection over the Charlotte
metro shifts east and out of the forecast area. An isolated severe
storm will remain possible across mainly the southern portions of
Charlotte through midnight with the main threat being locally
damaging winds and hail up to quarter size. Thereafter, a lull in
activity is expected through a good bit of the overnight. Locations
that saw rain today will have a chance for fog development until
high clouds return in advance of the next round of storms. Intense
upstream convection is ongoing across the Ohio Valley with storms
rapidly organizing into a large QLCS. This line will race across
Kentucky and Tennessee overnight and will be on our doorstep during
the predawn hours (roughly 4-5am). Robust storms are anticipated to
move into the mountains where a threat for damaging winds and a
couple tornadoes will exist. CAMs have been consistent in wanting to
rapidly weaken the line as it moves through the mountains with only
a band of showers and a few thunderstorms surviving into the
Foothills/Upstate. At least a low-end severe threat may persist east
of the mountains should the line maintain intensity longer than
indicated by guidance.

Otherwise, a final round of storms will be possible during peak
heating on Monday, but will need a few factors to come together for
it to reach its full potential. This one will be dependent on how
much the environment recovers from the early morning convection and
if the atmosphere regenerates more instability. As of now, CAMs do
exactly that, with dewpoints in the uppers 60s to near 70 and
instability quickly redeveloping by peak heating, ahead of an
incoming cold front. Deep layer shear will remain elevated (35-45
kts) and curved hodographs would support rotating supercells on
Monday. The question will be if we can tap into any surface
instability to take advantage of the otherwise really good
kinematics in place. If instability becomes realized Monday
afternoon, all three hazards will be possible (large hail, damaging
winds, tornadoes) with upscale growth by the time the storms get
into the eastern zones and east of the CFWA. The only thing about
this forecast is that it will remain uncertain until we see what
happens with the second round of convection that`s expected
overnight. Decided to lower temperatures slightly for Monday as
convective debris will be hard to shake off, especially during the
morning hours. As a result, afternoon highs on Monday will be at or
slightly above normal.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
As of 135 PM Sunday...Upper heights remain nearly zonal Tue which
will help maintain dry conds and temps warming about 5-7 degrees abv
normal. Surface td/s will mix out deeper than Mon and expect lower
RH values making for a rather nice feeling day. Heights and
thicknesses begin to drop Tue night thru Wed and with a cP airmass
mixing in, don`t envision a good chance of precip associated with
incoming mlvl s/w Wed afternoon. So, kept the fcst dry and again
another nice feeling day with low RH and highs closer to normal. Dry
conds continue thru the overnight periods and really no good chance
of dense fog as sfc tdd/s generally average arnd 10 F across the
fcst area.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
As of 145 PM Sunday...No sigfnt changes were made to the ext range
fcst. Still expect a mostly dry period as the mean h8-h5 flow aligns
w/ly to nw/ly and continues to reinforce a cP airmass building down
the east coast. The latest GFS swings a rather strong h5 s/w thru
the pattern Fri, but moisture looks too limited to introduce precip.
The going showery activity was maintained Sat as another ulvl wave
approaches from the west which will have a better llvl GOM
connection. Deep convection looks limited with this system, however,
as the wave runs into a strong ridging aloft possibly subduing tstm
development. Temps will remain arnd normal levels each and a limited
fog potential continues each night due mainly to sfc dryness.

&&

.AVIATION /02Z MONDAY THROUGH FRIDAY/...
At KCLT and elsewhere: Showers and thunderstorms continue to impact
the area with temporary restrictions possible at all terminals
through the evening hours. A break in the storms is expected
overnight before a second line of convection moves through the area
during the early to mid morning hours. Associated visibility and
ceilings restrictions can be expected. Thereafter, gusty winds are
expected through the afternoon. A final round of storms will be
possible during the afternoon hours, but confidence is low as to
whether this activity will be able to develop.

Outlook: Drier weather is expected by midweek.

&&

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

&&

$$

SYNOPSIS...DEO
NEAR TERM...CAC/TW
SHORT TERM...SBK
LONG TERM...SBK
AVIATION...TW