823
FXUS62 KGSP 281834
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
234 PM EDT Sun Apr 28 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. A stronger front is expected to approach
the Carolinas by late week and bring more showers and thunderstorms
to the area.

&&

.NEAR TERM /THROUGH MONDAY/...
As of  150 pm Sunday: Heights will fall across the region during the
near term...especially the latter half of the period, as upper ridge
axis progresses to the East Coast...downstream of a trough axis
advancing east of the Miss River on Monday. Low level flow
trajectories off the Atlantic are resulting in widespread stratocu/
cumulus across the area this afternoon...particularly across the
southeast quadrant of the CWA. Cloud tops are bubbling starkly per
visible imagery, and regional radars indicate some very weak returns
in association with some of the taller clouds. However, IR imagery
indicates cloud tops are jutting into the prominent subsidence
inversion evident on 12Z Raob, and little additional vertical
development is likely. Thus, while some locations could see brief
sprinkles, chances for measurable precip are < 20%.

As deep layer ridging moves east of the area tonight into Monday,
low level flow is forecast to become increasingly SW, which is
expected to result in less cloud cover tonight and Monday. Decent
radiational cooling conditions should follow tonight, and min temps
are expected to cool to just slightly-above-climo. Elevated
near-surface moisture could allow for some patchy fog development,
particularly in the climatologically favorable locations in the
mountain valleys. Sunnier conditions combined with increasing
thickness values should allow max temps Monday to warm to around 5
degrees above normal.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
As of 1:45 PM EDT Sunday: Upper ridge over the East Coast will still
be in place as we move into the short term, with the trough that has
been causing all the problems in the Southern Plains lifting and
damping as it pushes east. Occluded front will approach the
Appalachians at the start of the period, weakening on the southern
end as it competes with the hefty ridge. Pops move into western
zones before daybreak and ramp up during the afternoon hours,
especially over the mountains, but the high elevations really tears
the low level features of the front up. Very little deep layer shear
to work with (not even 30kt collocated with the best instability)
and even the more unstable NAM keeps SBCAPE less than 1000 J/kg. So
for now, general thunder looks good, but can`t rule out that one or
two may be stronger to marginally severe. Temps should be several
degrees above normal on Tuesday with southerly flow still around the
surface high off the Atlantic, even with the shortwave and front
coming through.

The shortwave passes through quickly and ridging builds right back
in on the back edge. Under full sun, temperature will climb a few
degrees higher for highs on Wednesday, probably a good 10 or
so degrees warmer than seasonal normals.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
As of 2:15 PM EDT Sunday: Upper ridge is still in place as we move
into the extended Wednesday night into Thursday, with another
shortwave diving out of the Rockies into the Plains. Increasing
disagreement in how this system is handled in the global models, but
general picture shows another front pushing across the center of the
country Thursday and towards our area Friday. Should see another
uptick in temperatures on Thursday as the ridge strengthens, with
pops moving back in on Friday. For now this front looks a little
stronger than the early-week front, at least as far as instability
goes, so this will have to be monitored in case this trend holds in
future runs.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
At KCLT and elsewhere: VFR stratocu cigs in the 045-060 range are
expected to continue through the afternoon. This is expected to be
esp true at KCLT, while the more western terminals may see clouds
steadily decrease through the afternoon. There may be a brief period
of sprinkles at some Piedmont terminals (incl KCLT), but chances for
anything more than that are slim-to-none. Sky cover should diminish
in all areas this evening, with mostly SKC conditions expected to
develop by late evening/overnight. Some BR and even low stratus
could develop in the mtn valleys toward daybreak Monday, but any
restrictions are primarily expected to impact the valleys west of
KAVL. SW winds are 10 kts are expected to become southerly while
diminishing to 5 kts this evening, before returning to SW at around 10
kts late in the forecast period.

Outlook: Dry weather lingers through at least Monday afternoon. A
frontal system could bring a round of showers and storms to the area
on Tuesday, with more of a potential for isolated diurnal convection
on Wed/Thu. The next front could bring better coverage of showers
and storms Friday.

&&

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

&&

$$

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