408
FXUS62 KGSP 292320
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
720 PM EDT Wed May 29 2024

.SYNOPSIS...
A cooler and drier air mass will gradually build into the region
through the end of the week, with high pressure moving across the
region at the start of the weekend. Once the high moves off to our
east on Sunday, we should see a slow warm up with a return of the
mainly afternoon and evening showers and thunderstorms.

&&

.NEAR TERM /THROUGH THURSDAY/...
As of 600 PM EDT Wednesday: No major changes were needed this update
as the forecast remains on track. Still seeing dry conditions across
the CWA with few to scattered diurnal cumulus. Upper cirrus is
creeping in from the west and southwest and should gradually thicken
through the next several hours.

Otherwise, omega block is in full force across the eastern CONUS.
Water vapor imagery shows a trough over the upper OH Valley and
Northeast, with nearly cutoff embedded shortwave spinning near
Pittsburgh. Via this pattern, some degree of DPVA will occur over
our area this evening although the shortwave will pass by to our
north. Similar to yesterday, a relatively shallow convective layer
will be present beneath this feature but still capped by subsidence
inversion. Some congested or towering cumulus thus may be seen
across the CWA thru evening, perhaps resulting in brief, isolated
sprinkles, but chance of measurable rainfall still looks to be near
zero. Deep mixing will result in low-end wind gusts through this
evening, especially across the mtns.

A dry, reinforcing cold front will push across the area overnight
behind the departing shortwave, promoting a further decline in
dewpoints. Despite temps also trending a few degrees below normal,
the drying should make for a fog-free night once again, except for
the Little TN Valley, where patchy fog may develop. Temps likewise
end up a little below normal for Thursday. Another embedded
shortwave will rotate through the trough late Thursday but without
enough moisture to justify mentionable PoPs. Mixing won`t be as
deep, leading to lighter winds on Thursday. Cumulus will develop
once again Thursday afternoon and early evening.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
As of 1205 PM EDT Wednesday: No changes to the going forecast to
round out the month of May as we remain under dry Northerly flow
aloft on Friday.  In the wake of vort energy rippling toward the
base of eastern seaboard trough axis, full sunshine is expected with
Piedmont maximums around 80 along with surface dwpts well below
climo.  Progressive upper ridge axis builds into and translates
across the region on Saturday and the llvl flow will come around to
south. This will aid in boosting maximums a couple of deg F above
Friday`s readings.  The atmosphere will also become weakly unstable
Saturday afternoon, and coincident with weak Ohio Valley s/wv energy
skirting by, there could be a few showers developing in the NC
mountains.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 130 PM EDT Wednesday: Diurnally enhanced summer-like
thunderstorm chances return to the forecast for the latter half of
the upcoming weekend as a quasi-zonal wavy pattern develops atop the
SE CONUS.  In fact, there is little discernible change expected for
the daily sensible weather through the early part of next week as
triggering mechanisms for daily thunderstorm chances will be driven
by a mix of synoptic scale s/wv and mesoscale features, along with
the typical terrain aided forcing here in the southern Appalachians.
Temperatures will be warming through the period, maximums rising to
the early June climo on Monday, but into the upper 80s by Wednesday.
Along with a daily increase in sfc dwpts will promote summertime
heat and humidity by the middle of next week as well.

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
At KCLT and elsewhere: VFR through the 00Z TAF forecast period
thanks to dry sfc high pressure building into the region behind a
dry cold front tracking across the western Carolinas this evening
into tonight. A few VFR cumulus are lingering across the terminals
this evening but these should dissipate shortly after sunset. SCT to
BKN VFR cirrus has been streaming ENE into the region out of the
WSW. This cirrus should mainly impact the SC Upstate terminals and
KCLT over the next few hours. Winds are mainly NW/WNW this evening
but should turn more N after midnight east of the mtns. Wind gusts
should gradually taper off through the early evening hours. Winds at
KAVL should remain WNW through the 00Z TAF period. No fog is
expected to develop overnight at any of the terminals thanks to
drier air filtering in behind the cold front. Winds Wednesday
morning and early afternoon will toggle more NE east of the mtns and
may toggle back NW towards the end of the TAF period. However,
confidence on this is very low so maintained NE winds through the
rest of the TAF forecast period east of the mtns. Winds will be
lighter compared to the last two days, with no wind gusts expected
on Wednesday. Afternoon cumulus should return but will remain VFR.

Outlook: VFR conditions will persist ,along with with dry weather,
through the end of the workweek. Shower and thunderstorm chances may
return this weekend.

&&

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

&&

$$

SYNOPSIS...DEO
NEAR TERM...AR/Wimberley
SHORT TERM...CSH
LONG TERM...CSH
AVIATION...AR