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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KGSP 081843
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
243 PM EDT Sat Aug 8 2020

.SYNOPSIS...
A return to more typical isolated to scattered summertime
thunderstorm activity is expected over the weekend as modest
drying arrives from the west. Deeper moisture will gradually return
early in the week and support a more active pattern from Tuesday
onward.

&&

.NEAR TERM /THROUGH SUNDAY/...
-- Changed Discussion --
As of 240 PM EDT Saturday: Conditions have been fairly quiet
this afternoon with temperatures climbing well into the upper
80s given plenty of insolation. Temps are expected to rise a few
more degrees before capping off for the day. Even though
showers continue to develop across the FA but struggle to hold
together, do expect isolated showers and thunderstorms through
this evening with available moisture, little instability, and
weak troughing. Could not entirely rule out a strong/severe
storm, but confidence remains fairly low attm. Otherwise, quiet
conditions are expected tonight with fcst soundings indicating
the return of low stratus/fog early Sunday morning, mainly
across the mountain valleys. Min temps will fall to near normal.

With ridging aloft, weak sfc high pressure will continue to allow
for drier air to infiltrate into the area on Sunday. However, with
weak trough in place over the Piedmont, could not entirely rule out
isolated showers and thunderstorms east of the Blue Ridge given
limited available moisture and daytime heating. Max temps will climb
a few degrees above normal.
-- End Changed Discussion --

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
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As of 135 PM EDT Saturday: The short range begins with with an
ill-defined upper pattern and weak flow thru the column. This will
allow for persistent warm mid-levels Mon, which will help suppress
afternoon convection. Isolated to sct storms are probable across the
mtns as an h5 s/w ejects out of the Midwest and crosses the wrn
zones by the early evening. A quiet Mon night as soundings show
decoupling and virtually nil elCAPE. On Tue...another low flow day
as BL winds remain w/ly and aide in limiting convection outside the
mtns. There looks to be another round of vort energy crossing the
mtns by the late Tue afternoon...so relatively high chance PoPs will
be held across the wrn zones again. Soundings indicate limited
sbCAPE, yet a few storms may become stg/svr, while possible slow
moving or training cells across the high terrain could create hydro
issues. Overall...the suppressive environ will support abv normal
temps by a couple degrees, while mins are be maintained right arnd
normal levels.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
-- Changed Discussion --
As of 155 PM EDT Saturday: Not much change made to the ext range
fcst. The guidance is still in decent agreement with the ulvl
pattern becoming a little more conducive to deep convec outside the
mtns each day...mainly aided by better llvl GOM moisture. There will
likely be an active sfc bndry to the east of the FA Wed afternoon,
yet better overall coverage is anticipated as instability increases
from earlier in the week. By Wed evening...a well defined h5 trof
will traverse the OH/TN valleys and push a cold front to the NC
mtns. This front looks to broaden out and stall across the FA Thu
thru the ext range and elevate PWATS to arnd 2 inches, while
increasing the potential for more widespread tstms each afternoon.
With increased deep-layered moisture and convec cloudiness, max
temps will revert back to normal levels each day, or arnd 90 F
across the non/mtns and m80s across the mtn valleys.
-- End Changed Discussion --

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --
At KCLT and Elsewhere: Aside from lingering MVFR cigs at KCLT which
are expected to improve over the next hour, VFR prevails at the TAF
sites this afternoon with isolated showers and thunderstorms
possible through tonight, as noted by VCSH/VCTS and/or TEMPO groups.
Fcst soundings continue to suggest fog and low stratus late
overnight and early Sunday morning, mainly confined to the mountain
valleys. Given lower confidence on any activity outside of the
mountains, have kept VFR at TAF sites for now, MVFR/IFR at KAVL.
Expect conditions to improve after daybreak.

Outlook: Isolated diurnal convection will persist through Monday
with increasing chances returning by mid-week. Morning fog/stratus
restrictions will also be possible each morning, especially over the
usual mountain valleys. Otherwise expect VFR.

Confidence Table...

            18-24Z        00-06Z        06-12Z        12-18Z
KCLT       High 100%     High 100%     High 100%     High  93%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     High 100%     Med   61%     High  94%
KHKY       High 100%     High 100%     High  90%     High  88%
KGMU       High 100%     High 100%     High 100%     High 100%
KAND       High  87%     High 100%     High 100%     High 100%

The percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables are available at
the following link:

www.weather.gov/gsp/aviation
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...DEO
NEAR TERM...12
SHORT TERM...SBK
LONG TERM...SBK
AVIATION...12