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Area forecast discussion 
National Weather Service Greenville-Spartanburg SC
1044 am EDT Friday Jul 31 2015

Synopsis...
dry high pressure will build in behind a departing cold front today
and remain in place through the weekend. Low level moisture will
gradually return through next week as another cold front approaches
from the north.

&&

Near term /through tonight/...
as of 1030 am EDT Friday...forecast running pretty much on track
with not much in the way of sensible weather to write home about.
Despite the heat...a fairly nice day with dewpoints lower in the
wake of the weak frontal passage. Very little changes made to the
grids this morning...have updated temperatures and dewpoints based on
trends and it is possible that highs might be just a touch lower
than forecast but will continue to monitor. Probability of precipitation look good for
now...Storm Prediction Center day1 outlook does include extreme southeast portions of
the County Warning Area in general thunder but looking at the hrrr and other cams
seems we will be pretty hard-pressed to see convection today. Clouds
will continue to scatter out over the next couple of hours.

1045 UTC update...sky cover was updated form infrared satellite
imagery...resulting in a decrease. Probability of precipitation were adjusted down per
trends.

At 300 am EDT Friday...an upper ridge will slowly retrogress today and
tonight from the Southern Plains to the southern rockies...while an
upper trough amplifies over the eastern USA. A cold front will move
slowly south and out of our area...stalling near the coast of the
Carolinas and Georgia. Moisture associated with this boundary appears to
generally remain just southeast of our area...offering little support for
convection. Temperatures will run near normal today and tonight as
weak cool advection is offset by limited downslope warming flow in
light northerly winds.

&&

Short term /Saturday through Sunday night/...
as of 150 am Friday...quiet weather expected through the short range.
An upper trough remains across much of the eastern Continental U.S. With no
significant short wave energy moving through the trough. At the surface...
dry high pressure builds in across the area Sat and sun. Guidance
blend shows dew points mixing out into the 50s across the area both
days. This combined with relatively warm middle level air will lead to
little to no cape each afternoon...resulting in very low potential
for deep moist convection. A remnant cold front boundary will be
close but south of the area providing little to no low level
convergence for the area. Therefore...have gone with a dry forecast.
Expect temperatures to be near to a little above normal through the period.

&&

Long term /Monday through Thursday/...
as of 255 am Friday...guidance is in decent agreement through the
period. East Coast trough flattens through the period with westerly flow
developing across the area as heights rise. This allows a series of
short waves to move across or near the area. The dry high pressure
over the area slowly moderates then dissipates as a cold front drops
south toward the area. The cold front initially stalls...then moves
into the area Thursday as a low pressure area tracks from the Ohio Valley
off the middle Atlantic coast. The result is an increase in low level
moisture and instability through the period. The best forcing...and
resultant convection...will be Wednesday and Thursday...with a dry forecast Monday and
only isolated convection Tuesday across the mountains with the rising
heights and lingering high pressure Monday and Tuesday...temperatures will be
above normal. Temperatures slowly fall Wednesday and Thursday...but remain above
normal.

&&

Aviation /15z Friday through Tuesday/...
at kclt...VFR. Guidance does not favor visibility or ceiling restrictions.
Winds will generally favor the north or NE...with limited gust
potential. Convection is not expected today in drier air behind a
departing cold front.

Elsewhere...restrictions are not favored at taf sites by model
guidance...as drier air moves in behind a departing cold front.
Winds will generally favor the north...with only limited gusts.
Convection is not expected at taf sites this afternoon.

Outlook...expecting generally dry and quiet weather through the
weekend with a gradual increase in chances for showers/thunderstorms
and restrictions for the start of the new work week.

Confidence table...

14-20z 20-02z 02-08z 08-12z
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 95%
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: (must be lower case)

Www.Weather.Gov/gsp/aviation_tables

&&

Gsp watches/warnings/advisories...
Georgia...none.
NC...none.
SC...none.

&&

$$
Synopsis...rwh
near term...tdp
short term...rwh
long term...rwh
aviation...jat/tdp

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