Area Forecast Discussion
Issued by NWS Greer, SC

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FXUS62 KGSP 250225

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1025 PM EDT Sat Jun 24 2017

A cold front will move southeast across the western Carolinas and
northeast Georgia this evening and then settle southeast of the
region overnight. Drier and cooler air will start to spread in from
the northwest through the day on Sunday, with these conditions
persisting through much of the week. Moisture will slowly return
around an offshore ridge of high pressure toward the end of the week.


As of 10:15pm EDT Saturday:  Forecast continues on track with
showers exiting the region to the southeast over the next few
hours.  Temperatures are a little off in some locations due to
effects of precipitation and clouds, and tried to improve those.

Showers will continue to weaken and move southeastward, exiting
the CWA by midnight with a few residual widely scattered light
showers persisting in piedmont areas for a few hours beyond that.

Showers have been along a frontal zone ahead of a broad eastern
CONUS upper trough.  Front and trough will continue southeastward with
relatively cool and dry northerly flow behind the front.  Passage of
this boundary tonight marks the end of a wet period with clearing
skies on Sunday.  As Sunday afternoon will be clear, highs may
actually warm into the mid and upper 80s in piedmont areas, which
would be warmer by a few degrees than the highs today which had
cooler temps. due to rain and cloud cover.  Dewpoints will drop
throughout Sunday leading to cooler and much less humid temps Monday
morning and onward.  Winds are light and variable behind the front
and will remain light as mild northerly flow develops around surface
high forming over the Mississippi Basin.


As of 115 PM EDT Saturday: Mean upper trough continues to make
progress into the Eastern Conus allowing dry air through a deep
layer to overspread the region Sunday night and Monday. Still
expecting a precipitous tumbling of sfc dwpts and below normal
temperatures.  Upper trough axis progresses into the region on
Tuesday with s/wv energy progged to advect through it`s base.  Short
range model consensus is trending a tad more responsive with this
feature, and may wind up ringing out some showers acrs NW NC.
Tuesday should wind up being the coolest day of the week thanks to
more the way of cloudiness and an increase in northerly llvl flow.


As of 1230 PM EDT Saturday: Upper heights atop the SE Conus begin to
rise on Wednesday with llvl return flow just getting under way as
llvl ridge axis shifts to the coast. Little in the way of sensible
wx to speak of featuring temperatures and humidity levels below
climo. This trend continues into Thursday with an upward bump in max
temps and dwpts, but the atmosphere still should remain effectively
capped.  A return to summertime warmth and humidity is expected for
Friday and Saturday within the progressively more moist, unstable
and less suppressed enviroment featuring daily thunderstorm chances.


At KCLT and elsewhere Showers and thunderstorms along a front have
exited southeastward past all of the TAF locations this evening.
Passage of this boundary will begin the process of reducing the
chances for precipitation.  Winds behind the front are generally
variable and will gradually become more northerly to northwesterly
overnight as surface high pressure develops over the Mississippi
Basin.  TAFs show ending precipitation and generally improving
conditions with only some high clouds possible on Sunday.  Residual
surface moisture following recent rains may give some low CIGs and
fog tonight and tomorrow morning.  Also, Higher elevation locations
could see a few wind gusts to 15 or 20kt Sunday afternoon with
downslope flow and excellent mixing under clear skies.

KGSP and KGMU:  Some low stratus has formed over a limited area around
KGSP and KGMU.  As low-level winds become more northerly over the
next few hours, dry advection should eliminated this deck.

Outlook: Rain will be ending Saturday night as front exits the
region, with drying and improving conditions on Sunday.  Light winds
and mostly clear skies through Thursday as high pressure dominates
the weather.

Confidence Table...

            02-08Z        08-14Z        14-20Z        20-00Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High  98%     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  93%     High 100%     High 100%     High 100%
KAND       High  90%     Med   63%     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:




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