Asheville, North Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

627
FXUS62 KGSP 231503
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1003 AM EST Mon Dec 23 2024

.SYNOPSIS...
Cold high pressure moves off the East Coast tonight resulting in
temperatures returning to near or a little above normal from
Christmas through the end of the week.  Moisture will also increase
with rain chances increasing through the weekend then drying out to
start next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 941 AM EST Monday: No major changes to the forecast this
morning.  Brought dewpoints down a little to account for weak
mixing already evident in morning soundings.  Left the forecast for
tonight alone until the 12z HREF is available...but still think
the threat for any ice is minimal based on the morning guidance
that`s available so far.

Otherwise...relatively flat/zonal upper flow will linger over our
area today and tonight. Towards the end of the near-term period
early Tuesday, shortwave upper trofing will dive down over the
Great Lakes, but remain to our north. At the sfc, expansive high
pressure will gradually drift east today/tonight with the center
moving off the New England coast later tonight. Nonetheless, the
residual cold-air wedge will remain over our area thru most of the
near-term period. Towards the end of the period early Tuesday,
a weak low is expected to develop just off the Southeast Coast
and track NE. The deeper, wrap-around moisture associated with
this system appears to just barely reach our SE zones during the
last 6 hrs or so of the period. As such, I capped PoPs at slight
chance and keep any QPF just to our SE. My sfc temps are cold
enough to support frz rain between roughly 06 and 12z Tuesday,
but the lack of QPF keeps ice out of our CWA. Otherwise, the period
should be dry with temperatures remaining well-below climatology,
especially outside the mtns.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
As of 121 AM EST Monday: We should be rid of any light precip over
the southeastern part of the Charlotte metro area by mid-morning
Tuesday. It is worth mentioning that we still have a non-zero
threat for some light freezing rain first thing in the morning over
Union County NC, but the trend in the guidance is toward keeping
the measurable precip just to the east, so the precip probs are
certainly no better than the last forecast cycle, and barely
20 pct. Meanwhile, temps will probably be slowly warming around
daybreak if the precip develops, such that if anything reaches
the ground it will be in the form of rain with temps just above
32F. We`ll keep an eye on it. Otherwise, the middle part of the week
still looks relatively quiet. After weak low pressure moves away and
off the Carolina coast late in the day Tuesday, a nrn stream upper
ridge supports a new sfc high over eastern Canada ridging down east
of the mtns as another inverted ridge/dry cold air damming wedge
starting Tuesday night and continuing through Wednesday night. The
model blend retains some low precip probs over the western side
of the mtns as a holdover from previous GFS runs that had some
precip associated with a dampening wave lifting northeast, but
the 00Z model runs all have that system well to the west. We will
keep the mtns dry. In the end, we get a fcst that stays dry after
Tuesday morning, with temps generally at or slightly above normal.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 216 AM EST Monday: Still awaiting some clarity from the model
solutions for next weekend. At least the guidance agrees that
it will eventually rain again at some point late in the period,
and that it will be a rain event because we would appear to be
essentially cut off from any cold air sources. However, the timing
of the next system is all over the place, and especially in the
ensemble members, with no clear favorite. Before we get there,
an upper ridge building over eastern North America as an upper
blocking pattern develops will hold sfc high pressure in place over
eastern Canada that wedges down east of the mtns through Friday
and at least into Saturday. The wedge pattern should act to keep
temps within a few degrees of normal through the end of the week
in spite of the upper ridge building overhead. Meanwhile, a mean
upper trof will linger over the Plains because of the blocking
pattern. The confidence is fairly low because of the timing and
strength of a short wave that comes east across the srn Plains on
Friday or Saturday. The ECMWF and Canadian have a more open wave and
thus are faster with its arrival, while the GFS is more apt to cut
off a low and slow down the eastward progression. As a result, the
model blend tends to smear out the precip chances starting Friday
and continuing a chance of rain through the end of the period, not
favoring any particular day. Again, fortunately this next system
looks like it would bring only rain. With either a wedge remaining
in place, or a remnant cool pool east of the mtns, our severe
weather threat looks low for now. Temps will remain around normal.

&&

.AVIATION /15Z MONDAY THROUGH FRIDAY/...
At KCLT and elsewhere: Expect VFR conditions to prevail thru
the 12z taf period with broad sfc high pressure still in place
over the region. Skies should be mostly clear thru the bulk of
the period, except for some high clouds moving over the area
from the south later this evening. In addition, some mid-level
clouds will likely reach KCLT later tonight as a weak area of
low pressure develops off the Carolina Coast. Winds will remain
light thru the period, generally favoring a NE to ENE direction
outside of the mtns. At KAVL, they will pick up marginally from
the S to SE this aftn and then go light and vrb again later this
evening.

Outlook: Expect broad high pressure and mostly dry conditions to
persist thru midweek. The only exception will be a weak coastal
low that brings a slight chance of rain over the eastern terminals
late Monday night thru Tuesday morning, with a low-end chance of
lower clouds reaching KCLT.

&&

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

&&

$$

SYNOPSIS...PM
NEAR TERM...JPT/MPR
SHORT TERM...PM
LONG TERM...PM
AVIATION...JPT