405
FXUS62 KGSP 050543
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
143 AM EDT Fri Jul 5 2024

.SYNOPSIS...
Hottest day of the week expected on Friday. A cold front moves in
from the north on Friday night, increasing shower and thunderstorm
chances into the weekend. A typical seasonal pattern of afternoon
showers and storms will start Monday.

&&

.NEAR TERM /THROUGH TODAY/...
As of 145 AM Friday: Warm night so far, despite mostly clear
skies across the CWA. Update for the 06z TAFs, with the public
fcst looking in good shape.

Otherwise, the southeast will remain under relatively flat upper
ridging thru the near-term period. On Friday, a weak sfc boundary
to the west will approach our CWA helping to increase low-level
moisture across the area. Expect PWATs to approach 2 inches, es-
pecially over our southern zones. With temperatures expected
to reach the mid to upper 90s, the higher dewpts will likely
produce heat index values of 105 degrees across the majority of our
non-mtn zones Friday afternoon. As such, a Heat Advisory for those
counties remains in effect from 11 am until 8 pm on Friday. The
higher dewpts should also help produce considerably more sfc-based
instability on Friday. This will result in sct to numerous showers
and thunderstorms across our area for the aftn and evening, with
the best best coverage expected over the higher terrain. The severe
threat still appears minimal for most of our fcst area on Friday,
however SPC does have a portion of our NC mtn zones in a Marginal
Risk area for Day 2.  The main hazard will likely be gusty winds
from strong downbursts.

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY/...
As of 115 AM Friday...Upper heights begin to fall Sat as a weak sfc
bndry moves into the region. This front looks to stall just south of
the FA and provide a focusing mechanism for widespread convection
during the afternoon. The atmos remains quite moist during this time
with abv normal PWATS and with weak column flow, the stage may be
set for slow and/or back-building cells which could lead to flooding
issues by the later afternoon. The severe risk is not great as mlvl
LRs remain low-end and no sigfnt forcing aloft will be present,
however, a few cells could pulse to severe levels producing large
hail and damaging downburst winds. With dewpts remaining in the l70s
across the srn zones, HI values may once again reach advisory levels
as temps rise abv normal by a few degrees. On Sun, drier air will
work in from the nw/ly mostly abv the sfc, but close enuf to
vertically mix dewpts back to normal. The models have trended a
little drier with sfc hipres attempting to ridge in from the NW, yet
still expect areas east of the mtns to have the best chance of
convec along a weakening yet existing sfc bndry. High temps return
to more normal levels Sun while lows persist a few degrees abv
normal each night.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
As of 135 AM Friday...The ext range will see the return of a more
normal summertime pattern. Broad subTrop ridging will dominate aloft
and keep any major fronts north and west of the area, while a sfc
Bermuda High remains in a favorable position to maintain good
Atl/GOM moisture flux into the area each day. Soundings look real
similar each afternoon with warm mlvls and skinny sbCAPE yielding
arnd 1500 J/kg or less each afternoon. Triggering will remain low,
however, some models show weakening vort energy traversing the ridge
Mon afternoon. In any case, not anticipating any organized severe
threat as the column flow remains weak thru the period. However,
PWATS remain abv normal so the potential exists for slow-moving high-
precip storms to create isol hydro issues. Storms should have no
problem activating early on each afternoon as LCLs link up with LFCS
rather quickly in the moist environment. Thus, storm coverage will
likely become abv normal with the mtns zones receiving the highest
PoPs. Max temps return to normal levels with no good indication of
HI issues, while a moist atmos maintains mins a little abv normal.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
At KCLT and elsewhere: Other than some mountain valley fog, expect
VFR conditions this morning. The main concern will be convection
timing and coverage. Guidance in decent agreement on activity firing
across the mountains in the aftn, then slowly expanding/drifting
east into the Piedmont late aftn thru this evening. Have TEMPO
at KAVL and PROB30 groups elsewhere with timing of greatest
chances. But thunderstorm activity may be earlier or later,
so timing will be refined as time goes on. Winds will be out of
the SW, peaking during the aftn. Convection will wane late in the
06z TAF period, with plenty of lingering VFR-level cloudiness and
light wind.

Outlook: Diurnally-driven convection will continue each day thru
the weekend and into early next week, leading to sct showers and
thunderstorms and possible restrictions each afternoon/evening.
Fog and/or low stratus may develop each morning, especially over
areas that received rain the previous day.

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for GAZ018-026-028-029.
NC...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for NCZ036-037-056-057-068>072-082.
SC...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for SCZ008>014-019-104>109.

&&

$$

SYNOPSIS...CP
NEAR TERM...ARK/JPT
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...ARK