039
FXUS62 KGSP 291428
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1028 AM EDT Mon Apr 29 2024

.SYNOPSIS...
The warming trend will continue through mid week as high pressure
remains centered just off the Atlantic Coast. A weak cold front is
expected to move through the area on Tuesday bringing scattered
showers and thunderstorms. Another front is expected to approach
the Carolinas by this weekend and bring more showers and
thunderstorms to the area.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1020 AM Monday: An off-shore surface high continues to ridge
across the area making for dry conditions outside of an area of
cumulus and stratocu extending from the upper Savannah River Valley
into southwest NC. As East Coast upper level ridge finally becomes
unblocked and shifts east, surface high and associated ridge will
shunt farther east into the Atlantic, making for decent warm air
advection in the llvls in advance of an active cold front expected
on Tuesday. As low level flow weakens and veers, the atmos will
become relatively dry this afternoon as soundings show high LCLs and
a well defined subsidence inversion lowering across the wrn zones.
So, don`t expect much afternoon cloudiness unlike the past few days
and temps will respond with highs in the lower 80s non-mtns and
upper 70s mtn valleys. A pre/frontal environment sets up overnight
as the low levels moisten and mid/upper clouds also increase in
coverage thru daybreak. A few mech lift-induced showers could
develop across the far sw/rn NC mtns before daybreak and have
maintained mid-chance PoPs with isolated thunder before dawn. Mins
will remain a cat or so abv normal tonight due to WAA sfc mixing and
increasing column moisture.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
As of 3:05 AM EDT Monday: The short-term fcst picks up at 12z on
Tuesday with an embedded upper shortwave approaching our area from
the west. The shortwave will gradually translate over our area late
Tuesday into early Wednesday and help push the upper ridge axis off
the Atlantic Coast. The shortwave will then move off the Carolina
Coast late Wednesday with heights rebounding in its wake and upper
ridging amplifying again as the period ends early Thursday. At the
sfc, broad high pressure will be centered off the SE Coast with warm,
SLY low-level flow over our area as the period begins. At the same
time, a weak cold front will approach our CWA from the west and move
thru our area Tuesday aftn/evening. This timing should result in a
decent amount of sfc-based instability across much of our area (for
late April) when the boundary moves thru. Thus, sct to numerous showers
and thunderstorms are expected for Tuesday aftn/evening. This insta-
bility coupled with the above-mentioned upper shortwave may produce
some stronger thunderstorms over our area, but it`s doubtful that any
storms will become severe. Regardless, the boundary should be moving
east of our CWA by early Wednesday with weak high pressure sliding in
behind it. Temperatures start out about a category above climatology
on Tuesday and continue to warm thru the period.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 2:55 AM EDT Monday: The extended forecast picks up at 12z on
Thursday with upper ridging in place over the Southeast CONUS. Over
the next couple of days, numerous weak upper shortwaves will lift to
our north and towards the Ohio Valley region. At the same time, broad
upper trofing will morph into a complex upper low just west of the
Great Lakes by the end of the week on Friday. As we head into the
weekend, the active northern stream will suppress the upper ridge
across the Southeast as additional embedded upper shortwaves trans-
late NE and over our area. At the sfc, reinforcing high pressure will
migrate southward from New England on Thursday and eventually settle
just off the mid-Atlantic Coast on Friday. At the same time, a more
robust low is progged to eject out of the Plains and lift towards the
Great Lakes. This system will bring another cold front to our area as
the weekend begins. Most of the long-range guidance still has the front
moving thru our area on Sat with sct to numerous showers and thunder-
storms likely Fri aftn thru much of Sat. Weak high pressure slides in
behind the front on Sunday, although the operational models diverge
considerably wrt the synoptic pattern beyond this point. Temperatures
will start out well-above climatology on Thurs and moderate some over
the weekend, yet still remain above climo.

&&

.AVIATION /15Z MONDAY THROUGH FRIDAY/...
At KCLT and elsewhere: Surface ridging will dominate the pattern
thru the TAF period and help make for VFR conds all sites. Low cloud
development will be confined across the srn NC mtns, as LCLs remain
quite dry. No big VSBY issue either thru the morning hours. Winds
round the sfc ridge and align generally sw/ly to s/ly with low-end
gust possible mainly at KAVL and KHKY this afternoon.

Outlook: A frontal system could bring a round showers and storms to
the area on Tuesday, with more of a potential for isolated diurnal
convection on Wednesday and Thursday. The next front could bring
better coverage of showers and storms on Friday.

&&

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

&&

$$

SYNOPSIS...JPT
NEAR TERM...JDL/SBK
SHORT TERM...JPT
LONG TERM...JPT
AVIATION...SBK