664
FXUS62 KGSP 250012
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
812 PM EDT Fri May 24 2024

.SYNOPSIS...
Temperatures will remain above normal through the holiday weekend
with a chance of afternoon and evening thunderstorms. A cold front
on Monday brings a better chance of showers and thunderstorms.
Cooler and drier conditions move in behind the front and remain
through the end of the work week.

&&

.NEAR TERM /THROUGH SATURDAY/...
As of 800 PM EDT Friday: Isolated strong-to-severe convection is
ongoing across the area this evening. Coverage has been diminishing
over the past hour or so, especially as the activity has been moving
into a more stable air mass across the eastern half of the CWA.
Isolated showers and storms may continue to bubble through the
evening, but the chances for severe storms should steadily diminish
over the next 1-2 hours.

Some CAMs, particularly the HRRR, continue to blow up scattered (if
not higher) coverage of convection toward daybreak. This trend has
been consistent enough that PoPs may need to be ramped back up circa
09Z in later forecast updates. Areas that get rain this evening can
expect some patchy fog before dawn, but that won`t last long before
skies clear. Lows will fall into the mid-60s again. Another round of
convection is expected tomorrow, but should be even less active than
today. Weak ridging will begin to develop over the Southeast CONUS
overnight, and the only supporting upper feature for convection will
be an embedded shortwave that dips across the Appalachians and into
the Piedmont by afternoon. CAMs suggest that a line of showers and
thunderstorms will cross the area during the mid-afternoon,
organized more by their supporting upper feature than by any
inherent storm-scale dynamics.  Sans much of an upper wave to work
with, there`s pretty good consensus that deep shear will be <20kts,
and so severe risk looks muted compared to today`s.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
As of 200 PM Friday: A short wave ridge builds in on Sunday but
there is a short wave trough that weakens as it moves through the
ridge. Guidance has backed off on precip chances in response, with
chc PoP north of the I-85 corridor and slight chc along and south.
Have followed this trend as well. Any storms that do fire could
become severe with moderate instability and shear, along with dry
mid level air, in place. Precip chances increase late Sunday night
into Monday as the ridge moves east and a stronger short wave digs
across the area. PoP still favors the area north of the I-85
corridor with likely PoP and chance along and south. Severe storms
look less likely even though shear remains moderate. There is less
mid level dry air and low level lapse rates aren`t as steep. Temps
will be up to 10 degrees above normal both days, with 90 possible
along and south of I-85.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 220 PM Friday: A series of short waves dig out a trough across
the eastern CONUS which remains in place through the end of the
period. Moisture lingers behind the the cold front moving through
Monday night, keeping a small chance of convection on Tuesday. Drier
and cooler high pressure builds in for the rest of the period. Temps
will remain above normal on Tuesday then fall to near normal for
Thursday and Friday.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
At KCLT and elsewhere: Isolated convection is ongoing across the
Terminal Forecast Area this evening. Most of the activity is
concentrated near KGSP, so tempos for TSRA are included for the
first hour there, as well as at KGMU. VCSH or VCTS is carried at the
other sites (with the exception of KHKY). This includes KCLT, where
confidence is waning that convection will occur this evening, so
VCSH has replaced the tempo for TSRA. Having said that, some of the
high resolution guidance is redeveloping convection overnight in
association with a weak upper air disturbance. For the most part,
the current TAFS reflect little in the way of convective activity
after midnight, but this may need to be revisited later this
evening. Otherwise, VFR conditions are generally forecast through
the period, although some 4-6SM BR is possible toward daybreak,
especially in the mtn valleys (including KAVL). Winds will generally
be light and variable overnight, and light westerly during the
daylight hours Saturday. Isolated to widely scattered convection is
expected to develop again Sat evening, warranting Prob30s for TSRA
at most sites.

Outlook: A unsettled pattern will linger thru the rest of the
weekend and into early next week, allowing for diurnal shower and
thunderstorm chances each day and at least patchy fog development
each night/morning.

&&

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

&&

$$

SYNOPSIS...RWH
NEAR TERM...JDL/MPR
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...JDL