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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KGSP 140233
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1033 PM EDT Sat Apr 13 2024

.SYNOPSIS...
Dry high pressure will linger to our south through the weekend
and into early next week, allowing temperatures to warm well-
above normal for mid April. Another frontal system will approach
our area by the middle of next week, and could bring showers and
thunderstorms to the region.

&&

.NEAR TERM /THROUGH SUNDAY/...
-- Changed Discussion --
As of 1030 PM EDT Saturday: Good radiational cooling conditions will
be in store and have lowered overnight lows by a degree or two
across the area as the boundary layer is expected to mostly decouple
overnight. Only minor adjustments made based on current observations
and latest model trends. Otherwise, the forecast remains on track.

Over the next 24 hours, the height gradient aloft gradually weakens
and the flow gradually backs more westerly as the upper trof off the
East Coast moves away. The pattern favors keep sfc high pressure
hanging out over the Deep South and keeping us dry. Min temps
tonight should be close to normal, perhaps balanced by some high
clouds if some orographic cirrus develops in the pre-dawn hours. The
air mass continues to modify into Sunday, and with some continued
westerly downslope flow, temps will climb thru the 70s in the
afternoon and may top out around 10 degrees above normal. That being
said, the previous forecast was trimmed back by a degree or two
based on the guidance blends. It will remain dry through the
afternoon, but the RH is not expected to mix down as much as the
last few days.
-- End Changed Discussion --

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
As of 2:25 PM EDT Saturday: The short-term fcst picks up at 00z on
Monday with long-wave upper trofing centered well to our north over
southern Quebec and broad, relatively flat upper ridging building
atop our region. A weak, embedded upper shortwave will translate over
our area late Sunday into Monday, but will likely provide little in
the way of upper support. Otherwise, upper ridging will persist over
our region thru the period as another upper trof cuts off a closed
low over the SW CONUS and lifts it NE towards the Great Lakes. At
the sfc, broad high pressure will be moving off the Southeast Coast
as the period begins. At the same time, a weak cold front associated
with the above-mentioned upper shortwave will move thru our area.
The front should not have much impact on our sensible wx other than
some brief low-end PoPs over our northernmost zones on Monday. For
the rest of the period, we can expect warming SLY to SWLY low-level
flow to persist over our area as we remain under the influence of
the Bermuda High. By the end of the period late Tuesday, a robust
low will eject from the central Plains and move another cold front
eastward and towards our region.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 2:15 PM EDT Saturday: The extended forecast picks up at 00z on
Wednesday with upper ridging in place over the Southeast and a robust,
closed upper low moving out of the central Plains. Over the next 24 to
36 hrs, the upper low will move up and over the upper ridge causing it
to flatten. At the same time, the low will get absorbed by a reinforcing
upper trof/closed low that dives SE out of central Canada. This system
will continue to translate SE thru the end of the period and likely be
centered somewhere over the eastern Great Lakes by the end of the period
next Saturday. At the sfc, our area will be under weak SLY low-lvl flow
and the western fringe of the Bermuda High as the period begins. Over
the next 24 hrs or so, a robust low pressure system will eject from the
Central Plains and move a fairly dry cold front thru our CWA late Wed
into Thursday. In its wake, the sfc pattern remains progressive with
another low spinning up just behind the first low and moving another,
potentially stronger cold thru our area on Friday. As for the sensible
fcst, no major changes were made. I kept PoPs in the slight to solid
chance range on Wed for the first frontal system with more widespread
chance PoPs for the second frontal system on Friday. Temperatures will
remain well-above climatology thru Friday with values cooling to near-
normal, if not below, by the end of the period next weekend.

&&

.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
At KCLT and elsewhere: VFR conditions will prevail through the
forecast period at all TAF sites. Clear skies with winds subsiding
overnight. Mountain wave cirrus can`t be ruled out early Sunday
morning. Light westerly winds will be in store overnight, then pick
up out of the southwest by mid-morning Sunday, with some low-end
gusts possible during peak heating.

Outlook: VFR conditions will persist through early next week as
high pressure builds across the region.

&&

.FIRE WEATHER...
-- Changed Discussion --
Although relative humidity values are not expected to be quite as
low on Sunday, they will likely approach critical values again
across much of our area. In addition, winds will be gusty again
Sunday afternoon and early Sunday evening and fuel moistures will
likely be lower than today. As such, Fire Danger Statements may
be needed for parts of our area for Sunday.
-- End Changed Discussion --

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
GA...None.
NC...None.
SC...None.
-- End Changed Discussion --

&&

$$

SYNOPSIS...JPT
NEAR TERM...CAC/PM/Wimberley
SHORT TERM...JPT
LONG TERM...JPT
AVIATION...CAC
FIRE WEATHER...