-- Discussion containing changed information from previous version are highlighted. --
148
FXUS62 KGSP 120234
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1034 PM EDT Wed Sep 11 2024

.SYNOPSIS...
The remnants of Francine are expected to drift north over the lower
Mississippi River Valley through late week with a broad area of
moisture moving north from the Gulf of Mexico to the Carolinas. This
will result in periods of showers and thunderstorms for our area
mainly Friday and Saturday. Scattered showers may linger through
Sunday with an area of low pressure potentially developing off the
Carolina coast that may keep rain chances across the area into
the middle of next week.

&&

.NEAR TERM /THROUGH THURSDAY NIGHT/...
-- Changed Discussion --
As of 10:15 PM Wednesday: Precip remains well to our south late
this evening with a fair amount of dry air still in place across
our CWA. The broad area of cirrus has spread across our entire CWA
with bands of sct mid-lvl clouds approaching from the south. This
cloud cover should limit any fog to the normally more fog-prone
Little TN valley. Despite the cloud cover, low temps should bottom-
out a few degrees below climatology Thursday morning.

Otherwise, broad sfc high pressure will continue to ridge down from
the New England Coast east of the Appalachians in wedge-like fashion.
TC Francine will continue to move northward and over Mississippi on
Thursday. The system is expected to be centered somewhere over NE
Arkansas by the end of the near-term period early Friday. Mostly
dry conditions should continue for our fcst area thru most of the
period. Deeper moisture will steadily increase from the south thru
the day on Thursday along with weak isentropic lift developing in
the SLY mid-level flow. Clouds should lower and thicken as well.
Precip chances will increase during the afternoon, but I don`t have
any likely PoPs over our area until roughly 00z Friday. Still expect
any QPF that does materialize to be light thru tomorrow night as the
stronger forcing remains west of our area. With the wedge pattern
setting up on Thursday, high temperatures should remain about 1 to
2 categories below normal for most of our area.
-- End Changed Discussion --

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY/...
As of 123 PM EDT Wednesdsay: Expectations remain similar, in broad
strokes, to similar forecasts going into Friday.  The latest 12z
suite of deterministic guidance has continued to shift the axis of
strongest low-level moisture transport southward, resulting in lower
QPF for the NC zones through the end of Friday.  There remains the
issue of a frontogenetical band possibly resulting in locally-
enhanced rainfall over the western Upstate or extreme southwest NC
mountains, but even this feature is displaced south in the latest
deterministic guidance, and an inspection of the LREF ensembles
lends little additional support for the idea.  Saturday is also
trending drier, with the bulk of long-range ensembles keeping the
stronger moisture transport and surface front displaced south of
earlier forecasts...once again limiting rainfall.

All told, the latest storm total rainfall estimates fall under 2.25"
for all but a few localized areas along the SC Blue Ridge Escarpment
through Saturday.  Even without the dry antecedent conditions amid
ongoing drought in many of these zones, this forecast should keep
concern for hydro issues limited.  Under such a regime, any hydro
issues would almost certainly be related to embedded convection
resulting in locally high precip rates and/or training.  Otherwise,
temperatures will remain well below normal as low-level cool air
filters in from the northeast only to be further cooled by falling
rain.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 154 PM EDT Wednesday: Of somewhat greater interest will be the
potential development of a secondary low off the SC/GA coast Sunday
as cyclogenesis gets going along an extant boundary draped across
SC.  This is a fairly new feature in the long-range guidance, but
one that, over the last 24 hours, has become the favored solution
for the LREF ensemble system.  The loss of strong circulation
associated with Francine`s remnants will temporarily shut off
whatever moisture/forcing are in place at this point, resulting in a
lull in rainfall on Sunday. Then, all the deterministic models and
fully 60-70% of global ensemble members depict the low curving
westward and slamming into the Carolinas with a second round of
rainfall.  It`s certainly too far out to start speculating on
impacts, but should this feature remain in the forecast for a few
more model cycles, it`ll become a point of focus over the coming
days.

&&

.AVIATION /03Z THURSDAY THROUGH MONDAY/...
At KCLT and elsewhere: Expect VFR conditions to continue thru the
00z taf period at all terminals. The likelihood of precip reaching
the fcst area increases significantly just as the current taf period
is ending tomorrow evening. Thus, the likelihood of associated re-
strictions will also increase for the next taf period. I did include
a PROB30 for RA at all taf sites except KHKY for the last few hours
of the period. Otherwise, sct to bkn cirrus will persist over the
area thru most of the period. Stratocu and altocu will increase from
the SW during the day on Thursday with cigs eventually becoming low-
end VFR. Outside of the mtns, winds will start out ELY this evening
and back to more NELY overnight. They will pick back up from the ENE
by late tomorrow morning/early aftn with low-end gusts likely at all
sites except KHKY. At KAVL, winds will continue to favor a S to SE
direction thru the period with low-end gusts expected tomorrow aftn/
evening.

Outlook: Restrictions may develop late Thursday as deeper moisture
moves in from the Gulf and Atlantic and gets drawn into the circula-
tion around Francine. Restrictions become more likely on Friday and
thru the weekend. Another tropical low may move over our area from
the SE on Monday, bringing more precip and restrictions.

&&

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

&&

$$

SYNOPSIS...DEO
NEAR TERM...JPT
SHORT TERM...MPR
LONG TERM...MPR
AVIATION...JPT