Brevard, North Carolina Weather Forecast Discussion

834
FXUS62 KGSP 301741
AFDGSP
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
141 PM EDT Tue Sep 30 2025
.SYNOPSIS...
Dry high pressure ridging down from the Northeast States will
control our weather, bringing cooler than normal temperatures for
Thursday and Friday.  As the center of high pressure moves to
offshore from the mid Atlantic states, temperatures return to near
normal for the weekend.  Moisture increases by Sunday and early next
week.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
As of 1124 AM Tuesday: Hurricanes Humberto and Imelda will continue
to move east away from the coast as a broad upper trough draped
across the Canadian Maritimes provides a route for northern passage
of the tropical cyclones. This leaves a general area of weakness
across the east coast as a tall ridge builds over the Mississippi
Valley. At the surface, high pressure is forecast to translate
across the far southern reaches of Hudson Bay/James Bay with copious
northerly flow through the column across the western Carolinas and
northeast Georgia. This will send a backdoor front through the area
later this afternoon through tonight with the boundary most apparent
in moisture/ThetaE fields. The boundary will scour out the plume of
moisture across the area with PWATs falling below 1", thus brining
an end to any lingering scattered showers. Cloud cover will also
diminish with mostly sunny skies returning Wednesday outside of any
scattered low-level cumulus. Cooler air will lag behind the boundary
with one last warm day on tap tomorrow with highs reaching into the
mid 70s to low 80s.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
As of 1215 PM Tue: 1030+ mb sfc high shifts south across the St
Lawrence Valley Wed night into Thu, supported by confluent flow
downstream of sprawling upper ridge over much of the eastern CONUS.
The sfc high will ridge down the Eastern Seaboard in classical
cold-air damming configuration. Dry weather is expected thru the
short term as a result, with Humberto and Imelda tracking out into
the open Atlantic and subtropical moisture shunted well to our south
by the damming high. Skies will be largely clear although there are
some indications of upslope clouds forming along the Blue Ridge Wed
night.
Cool northeast to easterly flow will continue Wed night into Thu,
with min temps Thu morning generally 5-10 degrees cooler than the
previous morning, the biggest drop being felt in the NC I-77
corridor. Max temps Thursday end up 3-5 below normal in most of the
CWA. Overnight lows cool a few degrees further Thu night, especially
in GA/SC and the NC mountains, though the cooling actually only
brings most of those areas back to within a degree or two either side
of normal. Higher elevations will dip into the lower 40s with some
exposed peaks falling into the 30s. Max temps Friday should be
similar to Thursday`s.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
As of 100 PM Tue: CAD would appear to weaken over the weekend, with
the parent high likely centered south of 40N by early Saturday and
with MSLP falling within. Via airmass modification and as low-level
flow turns more southeasterly, temperatures trend gradually warmer
Saturday thru Monday. Warming should be slowest in the typical "heart
of the wedge," the southeast-facing Blue Ridge Escarpment and NC/SC
foothills. As measured by LI and SBCAPE, strong subsidence should
persist Saturday. Thus, although dewpoints will begin to rebound,
PoPs remain near zero.
Upper ridge axis will migrate eastward and permit subtropical
moisture plume to shift northward Sunday and Monday on the southern
flank of the sfc high. Slight-chance PoPs develop near the Escarpment
by late Sunday and across almost all of the CWA by Monday. No true
erosion mechanism is seen for the CAD, and increasing moisture aloft
and weak upglide only would serve to reinforce any remaining wedge
via cloud cover and/or diabatic cooling from light precip. Hence max
temps manage to rebound to around 80 by Monday in the NC Piedmont and
some GA/SC zones southeast of I-85, but remain in the mid to upper
70s across the upper Piedmont where the wedge stands the best chance
of holding on.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
At KCLT and elsewhere: Conditions will gradually improve through the
TAF period as drier air arrives from the north and helps lift
ceilings and bring any lingering showers to an end. This will result
in a return VFR at all terminals by late this afternoon, if not
sooner. At least some degree of high clouds will linger overnight
before mostly sunny conditions return tomorrow. Mountain valley fog
cannot be ruled out at KAVL, but development will be conditional and
dependent on whether enough breaks in the clouds can occur for
radiational fog formation. Otherwise, gusty north/northwest winds
continue today with gusts subsiding overnight. A few gusts will
remain possible tomorrow as well.
Outlook: Dry high pressure is expected to remain over the region
into the weekend. Expect VFR conditions to prevail, with the
exception of patchy early morning fog and low stratus in the
mountain valleys each day.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.
&&
$$
SYNOPSIS...DEO
NEAR TERM...TW
SHORT TERM...Wimberley
LONG TERM...Wimberley
AVIATION...TW

NWS GSP Office Area Forecast Discussion