Bat Cave, North Carolina Weather Forecast Discussion

080
FXUS62 KGSP 041750
AFDGSP
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
150 PM EDT Sat Oct 4 2025
.SYNOPSIS...
High pressure continues to dominate the forecast the next few days
as temperatures warm up slowly.  Moisture returns early next week,
allowing cloud cover and rain chances to increase ahead of a cold
front, which should arrive on Wednesday.  High pressure and cooler
temperatures return toward the end of the period.
&&
.NEAR TERM /THROUGH SUNDAY/...
As of 130 pm EDT Saturday...
Key Messages:
1) Temperatures a Little Above Normal
2) Mountain Valley Fog/Low Stratus Again Sunday Morning
3) Small Shower Chances for the Upper Savannah Valley/Lakelands
Deep anticyclone will continue to meander off the Carolina/Mid-
Atlantic coast through the near term, resulting in continued/gradual
weakening of the inverted surface ridge in place across region. Flow
just about the surface turning to the SE around the periphery of the
weakening ridge is expected to result in advection of an Atlantic
moisture plume into mainly the southern/western part of the CWA by
late Sunday morning, resulting in increasing shower chances...albeit
only in the 20-30% range across the Lakelands region/upper Savannah
River Valley by afternoon. Otherwise, another round of fog/low
stratus is expected...mainly in the mountain valleys, but it may be
a little less widespread than Saturday morning owing to lingering
cirrus as well as the increased potential stratocu to develop prior
to fog formation. Min temps tonight are expected to be warmer than
in recent days...very close to normal. Maxes on Sunday should be
similar today...perhaps even a degree or two cooler owing to
increased cloud cover potential.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
As of 1214 PM EDT Saturday: The upper anticyclone centered over the
Eastern Seaboard will become increasingly lopsided Monday as a broad
area of confluent flow develops over the central CONUS.
In response, surface high pressure will drift farther and farther
offshore, steadily reducing synoptic support for the lingering
cold-air damming in place east of the Appalachians.  As a result,
the wedge will wind up orphaned and should slowly deteriorate
through the remainder of the short term.  Still not carrying a PoP
on Monday, but the latest operational GFS and ECMWF both depict a
lobe of stronger low-level isentropic ascent developing along an
axis from central Georgia into the CSRA and western SC Upstate
on Monday evening.  There`s some discrepancy among ensembles
over exactly how far north this upglide will find its focus,
which will determine how it affects us...but still think the
potential for isolated sprinkles late Monday is there.  Highs on
Monday will largely be dictated by thicknesses...as although the
upper anticyclone will begin to slide east by peak heating Monday,
thicknesses will remain anomalously high, and resulting temperatures
should wind up a solid category above normal for most of the area.
Tuesday, what`s left of the z500 high will retreat farther south and
east, eventually merging with the subtropical ridge over the Gulf
and western Atlantic.  Heights over most of the Eastern Seaboard
will fall as robust troughing intensifies over the Great Lakes and
southeastern Canada, while an elongated cold front slips into the
Ohio Valley.  By Tuesday afternoon, weak near-surface WAA should
support development of a decent mixed layer, scouring out clouds
across much of the low terrain...and especially areas south of I-85.
Highs will once again climb at a category or more above normal.
By the end of the period Tuesday evening, the front will likely
be entering the Tennessee Valley, though associated precipitation
doesn`t look like it`ll make it to the Carolinas until well after
nightfall.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 1231 PM EDT Saturday: Wednesday still looks to feature the
next opportunity for active weather...though using the phrase
"active" may be a bit of an overstatement.  The general consensus
is that the most-focused region of the advancing upper trough axis
will remain well north of the area, which in turn should keep the
better synoptic forcing somewhere over the Mid-Atlantic.  For us,
the lack of either DPVA or significant height falls means lapse
rates won`t improve much ahead of the front, and the incipient
dry air mass will make surface-based instability...difficult to
come by.  Most operational guidance depicts 

NWS GSP Office Area Forecast Discussion