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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KGSP 040747
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
347 AM EDT Sat Apr 4 2020

.SYNOPSIS...
High pressure will move north of the region today, then to our
east on Sunday. A weak cold front will push in from the northwest
by Sunday evening, stalling over the area Monday, before lifting
back north as a warm front on Tuesday. A stronger cold front will
cross the region on Wednesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 213 AM EDT: More mid-level clouds sooner than expected...and
now upstream radars are picking up some light precip over the
Cumberland Plateau. Some of the guidance brings the light precip
down over the NC mountains in the pre-dawn hours. Have some doubts
that any of this is reaching the ground, though. Will not rule out a
few sprinkles, but will not include any precip chance for now. Temps
were running warmer than fcst with the increasing cloud cover.

Otherwise, fair weather will continue for the next 24 hours as an
upper ridge moves overhead and dampens out, supporting weak high
pressure to the north. A chunk of the high eventually breaks off
over the Carolinas tonight. High temps should be similar to Friday,
although with more high cloud cover, it won`t be as pretty of a
day. Model guidance has thicker high cloud cover moving in tonight,
so min temps will be above normal. If there is a concern for the
near term, once again it will be minimum RH this afternoon, but
it should not be as low as Friday. See the Fire Weather Discussion
for more info.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 315 AM EDT Saturday: the short-term fcst begins at 12z on
Sunday with broad upper ridging over the area. The upper ridge is
expected to remain over the region thru the period and into the
extended period. At the surface, a weak cold front will move thru
the CWFA from the NW on Sunday. The models push the front offshore
on Monday and move relatively dry high pressure back over the area.
By early Tuesday, the high shifts SE which puts our area back under
warming SLY flow as a broad plume of deeper moisture spreads over
the CWFA from the west. As for the sensible fcst, PoPs will follow a
diurnal pattern on both Sunday and Monday with the best chances over
the higher terrain. Temps will remain above normal thru the period.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 255 AM EDT Saturday: the extended forecast picks up at 12z
on Tuesday with broad upper ridging still over the Southeast and
a vigorous closed h5 low developing over Southern California. On
Wednesday, the upper ridge will flatten over our region and on
Thursday, another broad upper trof digs down across the Great Lakes.
Beyond this point, the long-range models diverge considerably wrt
the large-scale upper pattern. The GFS, and to a lesser extent
the CMC, develop a massive upper trof and move it across the the
entire Eastern CONUS on Fri/Sat. The ECMWF, however, maintains flat
upper ridging over the Southeast and keeps the upper trof relegated
to our north. At the sfc, a broad plume of deep-layer moisture
associated with a weak cold front will be moving into the fcst area
from the SW as the period begins early Tuesday. By early Wednesday,
the front is expected to be east of the CWFA with the deeper moisture
pushed offshore. Beyond this point, the operational models diverge
considerably. The GFS develops a deep low over the Southern Plains
and quickly moves it NE pushing a strong cold front thru our area
early Fri. In the front`s wake, it spreads drying high pressure over
the CWFA for the remainder of the period. The ECMWF on the other
hand, moves a dry cold front quickly thru the fcst area on Thursday
with Canadian high pressure spreading back over the area in the
front`s wake. I didn`t change PoPs much early in the period but
I did increase them for Fri and Sat, although if the ECMWF pans
out, we`ll likely stay dry during that period. Otherwise, temps
will run well above climatology thru Thursday, before cooling back
down closer to normal, if not below, for Fri and Sat.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
At KCLT and Elsewhere: VFR conditions will persist through the
period. A bit more mid-level clouds thru daybreak, at least over
the west. Wind should be light from the NW or N. The clouds should
thin during the day, but will return in greater number late Saturday
afternoon. As high pressure moves past, wind will come around to
NE for awhile in the afternoon, but should continue to veer to
ESE in the early part of the evening.

Outlook: Expect VFR conditions to persist into early next
week. Flight restrictions may return on Tuesday as moisture
increases ahead of a weak front.

Confidence Table...

            07-13Z        13-19Z        19-01Z        01-06Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     High 100%     High 100%     High 100%
KHKY       High 100%     High 100%     High 100%     High 100%
KGMU       High 100%     High 100%     High 100%     High 100%
KAND       High 100%     High 100%     High 100%     High 100%

The percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables are available at
the following link:

www.weather.gov/gsp/aviation

&&

.FIRE WEATHER...
A Fire Danger Statement will remain in effect for Upstate SC through
today. The South Carolina Forestry Commission has opted to issue a
"Red Flag Fire Alert" for the entire state. We usually let that
speak for itself, but since the FDS has already been issued, we`ll
let it ride out to avoid confusion. Weaker winds as well as
increasing dewpoints (yielding min RH in the 25-35% range) are
expected Saturday, thus no additional products are expected at this
time for GA or NC.

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...Fire Danger Statement from noon EDT today through this evening
     for SCZ001>014-019.

&&

$$
SYNOPSIS...PM
NEAR TERM...PM
SHORT TERM...JPT
LONG TERM...JPT
AVIATION...PM
FIRE WEATHER...JPT