Area Forecast Discussion
Issued by NWS Greer, SC

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FXUS62 KGSP 230249
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1049 PM EDT MON AUG 22 2016

.SYNOPSIS...
High pressure will build in behind a departing cold front today,
bringing cooler and drier air to the area for the beginning of the
work week. The high will strengthen later in the week, allowing a
return to maximum temperatures that are well above average. Another
weak cold front will approach the Western Carolinas from the
northwest toward the end of the week, though limited moisture will
keep rain chances low and confined to the mountains.

&&

.NEAR TERM /THROUGH TUESDAY/...
As of 1040 PM: I will issue a quick update to tweak sky to satellite
trends. In addition, I will make minor tweaks to the hourly
temperatures and dewpoints.

As of 725 PM: Bands of thin cirrus should drift over the western
Carolinas and NE GA this evening and overnight. The center of sfc
high pressure will settle over the mid Atlantic region, providing a
light wind. Overnight winds over NC may favor a NNE direction, with
south winds across SC. NAM sfc condensation pressure deficits range
the lowest over extreme western NC, highlight valley fog and
stratus. H925 winds should remain out of SE, resulting in some
upslope flow. It is possible a brief period of fog and stratus may
develop around KAVL around dawn. Sfc high pressure should shift over
the Atlantic Tuesday afternoon, providing a light SE wind across
most of the region. Cloud cover should range from SCT over the upper
Savannah River Valley to FEW across the NC foothills.

As of 6 PM: Looks like a great evening. I will update the forecast
to align with recent observation trends. Overall the current
forecast is in great shape.

As of 200 PM: Large high pressure centered over the Ohio Valley
will move east, being centered over the Mid-Atlantic coast by Tue
aftn. Correspondingly the upper ridge will strengthen over the
Eastern CONUS. Deep subsidence within this pattern will suppress
convection over the CWFA thru the period. As the low level flow
veers to an Atlantic fetch tonight, a shallow moist layer does
develop beneath the inversion, extending from the Coastal Plain
into the upper Savannah River valley. Some model runs generate
QPF over this area at times during the next 24 hrs, particularly
in the early morning, but prog soundings reveal the layer is far
too shallow to permit precip to develop. Dewpoints are mixing
out enough this aftn that fog should be confined only to the most
favored locations, currently looking like the Little Tenn valley
and the northern foothills (Morganton-Lenoir). Temps are expected
to remain near MOS values, a degree or two below normal.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
As of 230 PM EDT Monday...Mid level ridging will build across the
southeastern states through this period. However,low level thermal
fields will lag by a few days keeping high temperatures in the 80s
on Wednesday outside the mountains, climbing to near 90 on Thursday.

Overall convective coverage will be below climatology. Most activity
will be limited to the normal favorable mountain areas during the
afternoon and early evening hours.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 200 PM EDT Monday...The medium range begins Thursday night
with the southeastern CONUS under the influence of a strong upper
ridge, and max temps well above average. A surface frontal boundary
will approach the southern Appalachians early Saturday...leading to
a small amount of airmass moistening over the weekend. The boundary
appears to largely wash out before it arrives, though, and with the
upper ridge still in place over the southeast, precip chances will
remain well below climo. In fact, the only pops featured through the
beginning of next week will be over the higher terrain, and even
then display limited coverage due to a general lack of moisture. The
upper ridge over the southeast appears to flatten and/or break down
early next week, allowing max and min temperatures to cool to near
or just above climo on Monday. Limited instability and more
substantial moisture also make a return early next week.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
At KCLT and elsewhere: VFR conditions expected east of the mountains
through the 0Z TAF period. Bands of thin cirrus should drift over
the western Carolinas and NE GA this evening and overnight. The
center of sfc high pressure will settle over the mid Atlantic
region, providing a light wind. Overnight winds over NC may favor a
NNE direction, with south winds across SC. NAM sfc condensation
pressure deficits range the lowest over extreme western NC,
highlight valley fog and stratus. H925 winds should remain out of
SE, resulting in some upslope flow. It is possible a brief period of
fog and stratus may develop around KAVL around dawn. Sfc high
pressure should shift over the Atlantic Tuesday afternoon, providing
a light SE wind across most of the region. Cloud cover should range
from SCT over the upper Savannah River Valley to FEW across the NC
foothills.

Outlook: The dry air will remain in place across the area resulting
in fair weather through at least mid-week.

Confidence Table...

            02-08Z        08-14Z        14-20Z        20-00Z
KCLT       High 100%     High 100%     High 100%     High  89%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     Med   73%     Low   56%     High 100%
KHKY       High 100%     High 100%     High  88%     High 100%
KGMU       High 100%     High 100%     High 100%     High 100%
KAND       High 100%     High 100%     High 100%     High  89%

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:

www.weather.gov/gsp/aviation

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.

&&

$$
SYNOPSIS...LEV
NEAR TERM...NED/Wimberley
SHORT TERM...SW
LONG TERM...LEV
AVIATION...NED



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