Area Forecast Discussion
Issued by NWS Greer, SC

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS62 KGSP 251726

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
126 PM 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.


As of 115 PM EDT: 1032 mb high pressure continues to build eastward
from the southern shores of the Great Lakes this afternoon. Shallow
ridging continues aloft with little moisture to be found in profiles
except for thin cirrus arriving from the northwest. The ridge will
settle overhead tonight through Wednesday with any additional
mid/high level moisture passing over the ridge axis to the north of
our area. Good radiating conditions will lead to another chilly
night of mostly upper 30s and 40s min temps. Patchy frost will once
again be possible around daybreak in sheltered NC mountain valleys
and over the northwest NC piedmont, but with coverage too low for
any advisories.

Southwesterly low level flow will then get slowly reestablished
through Wednesday as the surface high pressure center drifts toward
the eastern seaboard. Maximum temperatures will be comparable to
today as thicknesses are slow to recover.


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.


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


At KCLT and elsewhere: VFR conditions will continue through the
period at the TAF sites. The only location with much threat of MVFR
fog overnight will be the southwest NC mountain valleys as the
airmass modifies. Otherwise ENE winds early in the period will
toggle ESE to SE late this afternoon throughout. Some adjustment
back to ENE is likely overnight but winds will be very light and
will quickly toggle back to SE for good by late Wednesday morning.
Expect little more than a few cirrus throughout.

Outlook: High pressure will migrate offshore Wednesday night. A
fast-moving cold front will cross the area Thursday into Thursday
night, but with very limited moisture. Dry high pressure will return
Friday through the weekend.

Confidence Table...

            17-23Z        23-05Z        05-11Z        11-12Z
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:




AVIATION...HG is the U.S. government's official web portal to all federal, state and local government web resources and services.