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Area forecast discussion 
National Weather Service Greenville-Spartanburg SC
1015 am EDT Tue Oct 25 2016

seasonal and dry high pressure will remain over the region through
Wednesday...before a weak cold front crosses the area Thursday. Warm
high pressure returns Friday before another weak frontal passage
occurs late Sunday.


Near term /through tonight/...
as of 1010 am edt: temperatures were running a degree or so above
the forecast this morning. Good insolation and weak 850 mb
downsloping should offset cooler thicknesses and permit about a one
degree uptick in maxes in most areas. The only potential for any
cloudiness at all will be thin cirrus arriving aloft across the
northern tier this afternoon in the deep layer northwest flow. Otherwise,
high pressure will continue to ridge southweard from the Great Lakes
and western Ontario through tonight. Expect tonight to be seasonally
cool, perhaps enough for a few patches of frost in the normally
cooler spots across the NC foothills, NW Piedmont, and sheltered
mountain valleys. However, the extent will not be great enough to
warrant an advisory.


Short term /Wednesday through Thursday night/...
as of 130 am tuesday: a mixed cp airmass will continue to keep
temps arnd normal Wed with a little warming expected on Thu as the
llvl flow shifts SW/ly. A weakly forced cold front will cross the
area Thu and increased deep layered moisture along with some
lowering of sfc Theta/E will be the main factors in holding Max
temps right arnd normal. With a limited gom fetch...not expecting
much precip with this front...mainly across the higher terrain where
generally 0.25 inches or less will be possible locally. Will keep
pops in the low chance range mtns/fhills and slt chc non/mtns
throughout the fropa. The embedded S/W driving the front remains the front should push east of the fcst area by late
Thu. Winds will increase within the bndry layer Thu allowing for
relatively stronger winds mixed to the sfc producing low-end
afternoon gusts most locales.


Long term /Friday through Monday/...
as of 150 am tuesday: the Post cold-frontal airmass will actually
modify warmer on Fri as the upper pattern remains in a strong subs
pattern east of a strong sub-trop high center. A small scale sfc
Canadian hipres center will have little effect behind the front as
it/S absorbed within dominate atl ridging. Soundings show deep
layered drying which will allow for very good insol through the
weekend. With downslope warming assoc with llvl NW/ly flow...Max
temps shud reach arnd 10 degrees above each day...with some relative
cooling on Mon as sfc ridging assoc with a strong ern Quebec parent
high likely builds in from the NE during the day. No frost concerns
thru the period as mins are held in the lower 40s across the higher


Aviation /14z Tuesday through Saturday/...
at kclt and elsewhere: VFR is expected through the period. High
pressure well to our north will keep a light wind from generally the
northeast through the late morning hours. Some gradual veering to
east is expected this afternoon as a chunk of the high splits off
across the mid-Atlantic region. Late in the day, around 21z to 23z,
this could allow winds to come around to ESE, but the wind speed
will be 5 kt or less. A few cirrus will arrive from the west in the
mid/late afternoon.

Outlook: dry high pressure will persist through Wednesday night. A
fast-moving cold front will cross the area Thursday or Thursday
night, but with limited moisture. Dry conditions return for next

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 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...


near term...hg/PM
short term...sbk
long term...sbk

National Weather Service Glossary of Abbreviations