404
FXUS62 KGSP 250830
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
330 AM EST Mon Nov 25 2024

.SYNOPSIS...
High pressure will linger over the Atlantic Southeastern States
today. A passing cold front brings a chance for brief showers
early Tuesday, followed by dry weather on Wednesday. A second
frontal system will bring more widespread rain for Thanksgiving
Day followed by much colder temperatures for Friday and the
weekend.

&&

.NEAR TERM /THROUGH TUESDAY/...
Key Messages:

1) Dry and unseasonably warm conditions today.

2) Showers cross the area tonight, with rainfall generally light.

As of 300 AM EST Monday: Flat upper ridge axis will shift to the
East Coast today, as a shortwave trough enters the MS Valley. A
warm west-southwesterly flow will set up atop the forecast area,
as a cold front approaches from the west. This will make for
an unseasonably mild day, with highs pushing into the lower 70s
across much of the Piedmont and mid to upper 60s in the mountain
valleys. Skies should be sunny to mostly sunny with periods of
thin cirrus streaming by; although some lower clouds may bank up
against the SW-facing slopes in the far western mountains and NE GA.

Tonight, a low pres system will track into the Great Lakes with its
trailing cold front pushing into the forecast area overnight. The
front looks to have enough moisture for a band of light to moderate
showers along it. Instability looks quite meager, with MUCAPE of
less than 500 J/kg. Cannot rule out an isolated rumble of thunder
with the activity as it crosses the mountains, but chances seem too
low to mention in the forecast. Earlier guidance had the convection
struggling to cross the mountains, but the 00z runs and especially
the 06z HRRR have quite a bit of it cross the Piedmont late tonight
into early Tuesday morning. Overall, QPF will be light, but some
of the west-facing slopes of the NC mountains could see locally
0.5-1.0" of rainfall. With the increasing clouds and continued
warm SWLY flow, min temps will be well above normal, mainly in
the 40s Mountains and 50s Piedmont.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 3 AM EST Monday: The short-term fcst picks up at 00z on
Wednesday with upper trofing lifting NE and over New England.
This will result in relatively flat/zonal upper flow settling
over our area on Wed. By the end of the period early Thursday,
the upper pattern will begin to amplify again as broad upper
trofing begins to amplify to our northwest. At the sfc, a cold
front will be moving off the Carolina Coast as the period begins.
At the same time, transient high pressure will spread over the
Southeast in the front`s wake. The high`s presence will be short-
lived as it will be moving off the Atlantic Coast by late Wed.
As it does, another sfc low will eject out of the southern Plains
and track towards our area. Most of the latest model guidance has
this system lifting just north of our fcst area as the period is
ending early Thursday. In addition to widespread rain showers,
most of the model profiles have some amount of sfc-based insta-
bility across a good portion of our non-mtn zones on Thursday.
Thus, there`s a decent chance that we could get some thunder
as early as Thursday morning. The severe potential, however,
still appears very low.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 2:45 AM EST Monday: The extended fcst picks up at 12z on
Thursday with another round of broad upper trofing amplifying
over the eastern CONUS that will likely linger thru the weekend
and into early next week. At the sfc, a robust sfc low will eject
out of the southern Plains and track over our area just as the
period is beginning early Thursday. The operational ECMWF remains
the fastest solution wrt this system, but the GFS and Canadian
models have been trending faster over the past few runs and now
have the low lifting NE of our fcst area by Thursday afternoon.
They still don`t dry profiles out as fast as the ECMWF and are
about 12 hrs slower spreading high pressure back over our area
on Friday. Regardless, most of the long-range guidance has broad
(and cold) high pressure persisting over the Southeast thru the
weekend and into early next week. As for the sensible wx, Thanks-
giving still looks wet with the potential for a decent amount of
QPF across most of our CWA. I also still have some amount of NW
flow snow over the NC mtns early Fri, but at this time, it`s still
below Advisory criteria. As previously mentioned, temperatures
continue to trend colder towards the very end of the period early
next week with lows in the 20s across the lower terrain and lows
in the teens over the mtns.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
At KCLT and elsewhere: VFR conditions expected at all TAF sites
thru the period. Scattered thin cirrus will continue to stream by
thru most of the day, before becoming thicker this evening. Light to
calm winds overnight will increase to 5-10kts out of the southwest
during the day, with low-end gusts possible across the Upstate
sites this aftn.

Outlook: A weak cold front may bring scattered rain showers and
associated restrictions on Tuesday. Dry high pressure briefly
returns Wednesday. A more significant storm system may bring
widespread rain and restrictions on Thursday. Dry conditions along
with possible breezy NW winds return Friday.

&&

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

&&

$$

SYNOPSIS...JPT
NEAR TERM...ARK
SHORT TERM...JPT
LONG TERM...JPT
AVIATION...ARK