229
FXUS62 KGSP 110726
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
326 AM EDT Tue Jun 11 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. Otherwise, increasingly hot weather is expected through the
week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 300 AM EDT Tuesday: Any shower or thunderstorm from earlier
across the Upstate has diminished and now we are left with cloud
debris. Expect this to slowly scour out through the overnight
period. With drier air in place and some cloud cover overnight,
temperatures should cool to about a category below-normal across
the CFWA.

An upper-level low centered over the northeastern CONUS slowly
pushes eastward through the forecast period. In response, cyclonic
flow aloft will continue to overlay the CFWA as a shortwave or two
rounds the base of the upper low and allows for the trough axis
to shift east of the area during the daytime period Tuesday. Stout
northwesterly flow aloft filters in and a very dry airmass settles
in across the region, with weak continental high pressure remaining
in control through the near-term. Should see a few fair weather cu
during peak heating as the boundary layer becomes fully mixed, while
temperatures remain a few ticks below-normal as cooler than normal
thicknesses remain in place. 850mb temperatures around 14-15C and
applying the dry adiabatic method suggests high temperatures will
rise into the low 80s north of the I-85 corridor and mid 80s for
locations south of I-85, with 70s in the mountains. Good radiational
cooling conditions will be in store overnight tonight as mostly clear
skies and light and variable winds are expected as high pressure
sets up shop over the central/southern Appalachians. In this case,
overnight lows will run a few ticks below-normal.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
As of 300 am EDT Tuesday: The upper air pattern will become
increasingly summer-like during the short term, as the subtropical
jet steadily retreats to the northern half of the Conus, with weak
upper flow becoming increasingly anti-cyclonic with time over the
Southeast. Confluent flow to our north will support low level/dry
high pressure that will impact our air mass through the period. The
result will be inactive weather...with anomalously low surface
dewpoints and increasingly warm temps aloft precluding significant
diurnal destabilization/deep convection...although a couple of
ridgetop showers can`t be ruled out, esp Thu afternoon. Meanwhile,
conditions will become steadily hotter, with Thu afternoon temps
expected to be around 5 degrees above climo.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 315 am EDT Tuesday: A doubling-down on the trend toward
anticyclonic upper flow that begins late in the short term is
expected during the extended period, as high pressure is expected to
progress from the Southern Plains at the start of the period, to the
Southeast by the end of the weekend. As a result, the atmosphere is
expected to become increasingly suppressed through Sunday, with
precip chances primarily limited to isolated diurnal mountain
convection. The anticyclone may progress east of the area by the end
of the period, possibly allowing for more in the way of typical late
spring diurnal convective coverage on Monday. Otherwise, days will
be hot, with temps expected to average 1-2 categories above
climatology through the period...with some mid-90s forecast in the
Piedmont Friday and Saturday.

&&

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
At KCLT and elsewhere: VFR conditions will prevail through the
forecast period as weak high pressure remains in control. Earlier
showers across the Upstate has left the area with lingering cloud
debris, but bases remain 060-100 and should slowly scour out through
daybreak. Winds will favor a north to northwesterly direction
through the overnight and mid-morning hours. Some toggling in the
wind component will be evident by peak heating, with KCLT and KHKY
favoring a north to easterly component, while the Upstate sites
toggle around to more of an east to southerly direction. Model
guidance hint at a lee trough developing during peak heating as
well, so more variability in the wind direction will be present, but
based the 06Z TAFs on the current forecast. Otherwise, a few fair
weather cu may develop during the afternoon, so included FEW050 at
all TAF sites through 00Z Wednesday. Winds go light and variable
under mostly clear skies tonight. Some hints of mountain valley fog
is present overnight Tuesday, which may need to be included at KAVL
in the last line of the 12Z update.

Outlook: Sfc high pressure will remain over the area through at
least mid-week with little chance for convection and/or flight
restrictions.

&&

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

&&

$$

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