281
FXUS62 KGSP 041016
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
616 AM EDT Fri Apr 4 2025

.SYNOPSIS...
Mostly quiet and very warm conditions linger through Saturday. A
strong cold front brings rain and possible thunderstorms on Sunday
and Monday, before dry and chilly conditions return midweek.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 555 AM EDT Friday: Overnight temps didn`t cool as much as was
expected so made a few adjustments. Satellite shows low level
scattered stratus clouds throughout the CWA and high level clouds
from ongoing convection to the west.

Another muggy and warm day ahead for Friday. The ridge over the
southeast continues to amplify and high pressure remains parked in
place. S/SW surface winds reinforce moisture advection through the
period, increasing dewpoints and keeping the air soupy. The main
story through the near term are the temperatures that are
anticipated to approach record highs east of the mountains.
Additionally, with the southerly surface winds, there could be a few
showers that pop up in the mountains due to the upslope flow. Capped
PoPs at slight chance for this potential. Winds are expected to pick
up with some low-end gusts during peak heating times on Friday
afternoon. By Friday night, temps struggle to cool off as moisture
and patchy cloud cover remains in place. Overall, warm and humid
sums up the start of the weekend.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
As of 339 AM EDT Friday: Still looks like we should be able to
salvage the first half of the upcoming weekend as a large upper
anticyclone remains centered close enough to the Southeast Atlantic
Coast to keep the conveyor belt of moisture well to our NW thru the
day. Won`t be surprised by a few showers over the higher terrain of
southwest NC in the afternoon given the increasing moisture. Temps
will be the early story, with highs about 15 degrees above normal
on Saturday, which combined with the humidity, will make it feel
almost like early summer. Which brings us to the back half of the
weekend. The pattern will become slowly progressive at last from
Saturday night onward, with the upper ridge retreating farther
offshore and a wave lifting northeast out of the srn Plains
mid/upper trof. This should give a gradual eastward nudge to
the plume of deep moisture lifting out of the Gulf, bringing the
leading edge of precip to the mtns early Sunday morning. From there,
this deep moisture plume translates across the fcst area Sunday
and Sunday night. Impressive sustained DPVA and upper divergence
will support a wide band of precip crossing the region Sunday and
Sunday night. There are two main issues...excessive rain and severe
thunderstorm potential. First, the excessive rain. As it stands
for now, the QPF seems modest for the deep moisture transport
and forcing seen in the GFS, but that model seems more excited
than the others. The QPF we have, spread out over a 24-hour or so
period, looks more beneficial than scary at this time. We await
more guidance for potential for brief heavy rain before ramping up
the messaging. So for now, the Severe Weather potential might be
a little higher of the two. Guidance is in general agreement that
strong shear will translate east with a low level jet in excess
of 40kt during peak heating Sunday. Sfc-based CAPE looks modest at
best, maybe topping out in the 500-1000 J/kg range over northeast
GA/Upstate SC. But with that much shear, that will be enough CAPE
to support a Severe Thunderstorm risk. The passage of the LLJ will
decrease the shear and bring the threat to an end. After that, its
just a matter of the main short wave axis pushing the deep moisture
and precip eastward, which probably won`t happen until Monday. Temps
will start their cool-down Monday as the main cold front passes.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
As of 213 AM EDT Friday: A building consensus is seen among the
model guidance in moving the post-frontal precip out of the region
Monday evening as the main short wave axis pushes rapidly east
across the Carolinas. The passage of this wave will finally usher
in some cooler, more appropriate (?) weather for the middle part
of next week as a continental high pressure air mass moves in from
the NW. Note there are some model differences with how a trailing
wave dropping into the trof lags behind along the Gulf Coast, or
cuts off a low as shown in the GFS. Either way, this feature should
be far enough south as to not directly affect our weather. Better
agreement is seen among GEFS members with providing us a period of
seasonally cool and dry weather for Tuesday and Wednesday. The main
concern for the medium range will be the overnight lows Tuesday
night, which are expected to be on the order of ten below normal,
and down into the range that would easily support frost across much
of the area east of the mtns, with the exception perhaps of the
Lakelands. The cool temps will continue Wednesday night as well, but
modification of the air mass should be enough to lower the threat
of frost. We will keep an eye on this, now that the growing season
has started. Another clipper-like system is expected to drop down
from the NW later in the week, but for now the models are having
timing issues with its arrival. The model blend delays the precip
over the mtns until daytime Thursday after we warm up enough to keep
it rain. Precip probs are kept modest with a 30 mtns/20 Piedmont
and Upstate arrangement, but this could go up as timing becomes
more certain. Temps should rebound closer to normal Thursday.

&&

.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
At KCLT and elsewhere: A mix of IFR/MVFR to start the period as the
moisture continues to linger east of the mountains. Brief FG
possible through 13z at KAND. Lower cigs should start to lift
between 13z-15z, with KCLT returning to VFR conditions after 16z.
Other than intermittent FG at KAND, no vsby restrictions anticipated
as winds remain light to breezy. Winds today remain southerly veer
more SW Friday afternoon. Low-end gusts are likely across a few
terminals. Low level stratus is likely to develop tonight, bringing
back MVFR/VFR restrictions at terminals east of the mountains.

Outlook: Mostly dry conditions linger through Saturday night before
shower and thunderstorm chances increase flight restrictions to
start the week. Drier conditions return afterwards.

&&

.CLIMATE...
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      83 1999     33 1891     61 1893     22 1936
                1978
   KCLT      87 1999     43 1911     63 1986     29 1936
                            1899        1945
                                        1934
   KGSP      88 1963     44 1936     62 1999     25 1975
                1934



RECORDS FOR 04-05

               MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      86 1909     30 1891     60 2023     20 1944
                                        1910
   KCLT      88 1942     38 1891     62 1910     26 1891
   KGSP      90 1934     43 1899     60 2023     25 1904
                                        1888



RECORDS FOR 04-06

               MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      88 1967     36 1950     64 2023     22 1898
   KCLT      90 2010     43 1931     67 2023     28 1891
                1929
   KGSP      88 2010     47 1950     65 2023     26 1904
                            1945


&&

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

&&

$$

SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...PM
LONG TERM...PM
AVIATION...CP
CLIMATE...