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Area forecast discussion 
National Weather Service Greenville-Spartanburg SC
1024 PM EDT Mon Oct 24 2016

seasonal and dry high pressure will remain over the region through
Wednesday. A weak cold front will cross the area Thursday. High
pressure briefly returns before another weak frontal passage on


Near term /through Tuesday/...
as of 1000 PM EDT...the surface cold front continues to drop
southward through the southern edge of the County warning forecast area and should
completely clear thru the area overnight. Only a few locations in
sheltered northern mountain valleys appear cool enough for any
patchy frost formation, so no advisory will be issued. Lows mainly
in the 40s, except for some 30s in the mountain valleys.

Deep layer northwest flow will continue, with heights rising and the
pressure gradient relaxing through Tuesday. Surface high pressure
will build over from the north behind the front and push lower
thicknesses into the region. Weak downsloping will continue to
provide some measure of warming east of the mountains despite the
falling thicknesses - with maximum temperatures fairly close to


Short term /Tuesday night through Thursday/...
at 2 PM monday: on Tuesday evening an upper trough will be off the
East Coast, while an upper ridge will be over the Great Plains. The
ridge retrogresses over The Rockies on Wednesday while the eastern
trough progresses offshore, and another trough amplifies over the MS
River Valley. By Thursday the upper trough reaches the Great Lakes,
and the central and southern Appalachians, with an associated
shortwave crossing the mountains, while the upper ridge progresses
to the eastern slopes of The Rockies.

At the surface, on Tuesday evening a cold front will be well south
of our area, an high pressure will extend from the Great Lakes to
the Carolinas. High pressure persists over our area into Wednesday
night, finally weakening as a cold front approaches from the west
on Thursday. Meager moisture ahead of and along the front will limit
precipitation amounts, while instability will be limited for
convective development. Temperatures will run near normal.


Long term /Thursday night through Monday/...
at 2 PM monday: on Thursday evening an upper trough will be over the
eastern USA, while an upper ridge will exist along the east slopes
of The Rockies. The pattern progresses such that by Saturday the
Easter trough moves offshore, while the ridge upstream remains along
the Front Range, resulting in deamplification and more zonal flow.
By Monday the upper ridge progresses to the MS River Valley, while
the trough downstream moves little, and as a result, the upper
pattern amplifies.

On Thursday evening a cold front will be dropping south across our
area, with only limited moisture along the boundary. High pressure
settles in over our area on Friday and Saturday. Another cold front
reaches our area from the north on Saturday night, moving slowly
south of the area by Monday. Moisture with the second front will be
limited as well, and instability will be lacking. Temperatures will
run slightly above normal.


Aviation /03z Tuesday through Saturday/...
at kclt and elsewhere...a dry cold front continues to push south,
and as of the 00z taf time, as pushed south of clt and gsp. Winds
will favor a northwest direction this evening, then gradually veer to NE
overnight thru Tuesday morning. Wind speeds will be generally in the
5-9 kt range. By Tuesday afternoon, winds will become lighter and
veer to more east-northeast or east-southeast by end of the 00z taf period. With dry air
mass filtering in behind the front, only high clouds are expected,
mainly periods of thin cirrus.

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

Confidence table...

02-08z 08-14z 14-20z 20-00z
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...Ark/hg
short term...jat
long term...jat

National Weather Service Glossary of Abbreviations