-- Discussion containing changed information from previous version are highlighted. --
857
FXUS62 KGSP 121047
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
647 AM EDT Wed Jun 12 2024

.SYNOPSIS...
Dry conditions will continue through the week under weak high
pressure. Isolated to widely scattered showers and thunderstorms are
expected early next week as a weak cold front approaches from the
north.  The hottest days are expected to be Friday and Saturday,
then the heat should continue into next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
As of 640 AM EDT Wednesday: Serious cirrus roaming overhead the CFWA
with a new development of low stratus moving in from the south
across the Upper Savannah River Valley and southwest NC. Adjusted
the forecast to take this into account for the latest update. Not
expecting this to become widespread as daytime heating will limit
the expansion of this cloud deck. Mid-level Water Vapor imagery
shows the aforementioned shortwave over the Lower MS Valley and is
helping to enhance the deck of cirrus.

Otherwise, retreating upper trough over the northwestern Atlantic
will set the stage for rising heights and the flow aloft to somewhat
flatten out. Model guidance are picking up on a weak shortwave
moving across the Deep South during the period and will fetch a deck
of upper-level cirrus over the area. Weak surface high pressure will
continue to control the sensible weather as the high gradually
shifts offshore the Mid-Atlantic and Carolina Coast through the
period. Expect winds to steadily come out of the east to southeast
during the daytime period, providing a light Atlantic fetch across
the area. In this case, shallow moisture will settle at the top of
the boundary layer and underneath a mid-level subsidence inversion.
Expect more cloud cover than Tuesday as a result during peak
heating, but mentionable PoPs will remain out of the forecast due to
the warmer air aloft helping to suppress the atmosphere and no real
trigger for precip. Dewpoints will increase today to go along with a
rise in temperatures as our summertime pattern begins to really
settle in across the CFWA starting today. Expect afternoon highs to
rise around a category or so compared to Tuesday with most locations
reaching at or slightly above normal. Lingering cloud cover
overnight will keep what would be otherwise a very good environment
for radiational cooling. Overnight lows will be near normal as a
result.
-- End Changed Discussion --

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 250 am EDT Wednesday: Upper flow will become increasingly
anticyclonic during the short term, as high pressure gradually builds
toward the Southeast from the Southern Plains. The result will be a
continued warming trend, with rather hot conditions expected by the
end of the period. Meanwhile, despite steadily increasing humidity,
conditions will remain unseasonably dry as the atmosphere becomes
suppressed due to warming temps aloft/increasing subsidence. Some
short term and convection-allowing guidance seem rather overdone
with ridgetop convection Thu afternoon, as forecast soundings appear
quite inhospitable to deep convection. Still...we`re getting to the
point of the year in which it`s difficult to not get at least a
little diurnal convection going across the high terrain...so slight
chances for showers are carried there during the afternoon/early
evening. Much of the same can be said of Friday...although a short
wave trough passing north of the region is expected to send a weak
frontal boundary through our area during the afternoon.
Nevertheless, forecast soundings appear no less hostile to
convective development than they do on Thursday, so PoPs are once
again limited to late day ridgetop slight chances. Temperatures will
be above normal through the period, with Friday expected to the
hottest day of the year so far...with mid 90s expected across
portions of the Piedmont.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 300 am EDT Wednesday: Upper heights will continue to rise
during the early part of the extended, as anticyclone becomes
centered over the Southeast during the weekend, before likely
lifting into the Mid-Atlantic early in the new work week. As a
result, the atmosphere will remain quite suppressed for vertical
motion on Saturday, with sparse-at-most mountain diurnal convection
expected. As the anticyclone begins to drift away from the area
early next week, conditions will steadily become more favorable for
(mainly) mountain convection Sunday through Tuesday afternoon/
evening. In fact, some global models lift a short wave trough north
through the TN Valley and southern Appalachians by the end of
Monday, which could further increase the convective potential for
far western areas. In general, forecast PoPs trend toward
climatology early next week...20-30 PoPs mainly across the western
half of the area...with a small increase over these values Monday
afternoon. After another day with max temps 5+ degrees above normal,
conditions will moderate a bit thanks to falling heights, although
max temps are still forecast to be a couple of degrees above climo
through the end of the period. Increasing humidity will result in
above-normal mins.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
At KCLT and elsewhere: Mostly VFR conditions will prevail through
the forecast period. New development of low stratus with an MVFR
deck could cause minor issues to the current forecast across the
KAVL and the Upstate sites. Included an MVFR TEMPO for BKN018
through 15Z as the cloud deck is small signals of expanding into
these TAF sites. Winds will start with a northerly component before
toggling towards the south by mid-morning and beyond. High pressure
will remain in control through the rest of the period and keep winds
on the lighter side with mainly a south to southeasterly component
at 4-6 kts. FEW to SCT fair weather cu will develop once again
during peak heating with upper-level cirrus hovering overhead
through a good portion of the day as well.

Outlook: Surface high pressure remains over the area through the
end of the week with minimal chance for convection and associated
flight restrictions.
-- End Changed Discussion --

&&

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

&&

$$

SYNOPSIS...DEO
NEAR TERM...CAC
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...CAC