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fxus62 kgsp 060552 

Area forecast discussion
National Weather Service Greenville-Spartanburg SC
1252 am EST Fri Dec 6 2019

a low pressure system will move quickly across the southeast
tomorrow before dry high pressure briefly returns for Saturday. An
unsettled weather pattern will then set up starting Sunday
afternoon, with rainy conditions expected through Tuesday ahead of
an approaching cold front.


Near term /through today/...
as of 1245 am: upper flow will continue to flatten as an upper
trough lifts towards the northeast, while surface high will continue
to drift eastward through the next 24 hours, allowing for
establishment of southerly flow across the forecast area. A gradual
increase in cloudiness will continue through the morning as an upper
wave and surface low reflection move through the deep south. Chance
pops continue for the western 1/3 of the forecast area tomorrow
afternoon as the system moves through, though the best moisture,
most robust qpf, and best forcing will remain to our south. Very
light quantitative precipitation forecast (all rain) is featured in the public forecast through the
afternoon and evening before the system moves quickly eastward.
Temps are forecast to be very close to normal through the period.


Short term /tonight through Sunday/...
as of 240 PM EST thursday: with broad upper troughing across the
eastern conus, and broad upper ridging across the western conus, a
cold front will be just on the door step of the western Carolinas
and northeast Georgia at the beginning of the short term forecast
period, stemming southwestward from it's parent sfc low, which will
be in the midst of pushing of the NE coast. With SW flow/limited
available moisture ahead of this boundary, do expect light showers
to be ongoing Friday night, with a few snowflakes possibly mixed in
at the higher elevations. With activity confined to the boundary,
anticipate this activity to quickly taper off through the early
morning hours on Saturday, as the cold front exits to our east. Per
latest guidance, quantitative precipitation forecast looks to be limited with this feature.
Conditions will remain for Saturday and Saturday night as sfc high
pressure builds into the area, with dampened northwest flow slowly becoming
nearly zonal. Some model guidance continues to hint at the potential
for light showers across the upslope areas towards the end of the
fcst period, on Sunday. However, confidence remains low attm. With
this forecast package, have kept pops fairly low, with more opaque
cloud cover across the western portions of the, and less opaque
cloud cover over the eastern portions. Max temperatures will remain
below normal, slightly cooler on Sunday, than Saturday, with min
temperatures above normal Saturday morning, returning to near normal
Sunday morning.


Long term /Sunday night through Thursday/...
as of 255 PM EST sunday: with sfc high pressure wedged in place
across the Carolinas late Sunday into Sunday night, and nearly zonal
flow aloft, latest European model (ecmwf) continues to depict increasing shower
chances Sunday night, as northern stream trough begins to dig across
the central conus, and SW flow continues to allow for moisture to
infiltrate into our area. However, latest GFS delays the onset of
any precipitation until Monday around daybreak. With this fcst
package, as wedge retreats off to the north, and a warm front to the
south lifts northward through the area on Monday, have kept the
gradual increasing potential for showers throughout the day on
Monday. With the anticipation of temperatures above normal, expect
any precipitation that falls across the area Monday morning through
the evenings hours to fall as all rain. This unsettled weather
pattern is expected to persist into Tuesday, as a cold front pushes
through the area from the west, with temperatures nearly 10 degrees
above normal. Periods of heavy rainfall will be possible on Tuesday,
especially across the southern mountains. With amplifying upper
trough and the return of northwest flow behind the exiting front, cold air
will quickly infiltrate into the area for Tuesday night. As a
result, a rain/snow mix to snow showers will be possible across the
NC mountains. Attm, any snow accumulations look to remain low,
though could not entirely rule out a few inches at Mount Mitchell.
Elsewhere, rain showers will gradually taper off into late Tuesday
night. For Wednesday and Thursday, expect dry conditions to prevail
as sfc high pressure continues to build in with temperatures below


Aviation /06z Friday through Tuesday/...
at kclt and elsewhere: VFR conditions are forecast through the
period, with increasing mostly mid and high level clouds expected
through the morning in association with an approaching upper level
disturbance. Chances for rain will be highest over the mtns, but
only a prob30 is warranted late this afternoon/evening at kavl.
Sprinkles may fall at the other terminals, but certainly nothing
that would contribute to flt restrictions. Winds will by calm or
light/vrbl this morning, becoming light SW during late morning/early

Outlook: flight restrictions are likely to return sometime late
Sunday into early Monday with rain at times until a cold front
pushes through the area Tuesday.

Confidence table...

06-12z 12-18z 18-24z 00-06z
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 and ensemble forecasts
are available at the following link:



Gsp watches/warnings/advisories...



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