237
FXUS62 KGSP 141326
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
926 AM EDT Sat Jun 14 2025

.SYNOPSIS...
Seasonably warm and humid weather, with numerous showers and storms
each afternoon and evening, can be expected through the weekend. A
warming trend will begin on Monday, and daily showers and storms
will continue through most of the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 925 AM EDT Saturday: No major changes were made to the
forecast for the morning update. The few lingering showers that were
on radar have since dissipated. Low stratus clouds continue to break
through the CWA as the morning progresses.

Persistence looks like a good forecast for the near term, up to a
point. An old mid/upper trof over the mid-MS Valley region early
this morning will gradually fill and lift across the OH/TN Valley
regions through tonight, keeping our fcst area in the continued
southwesterly flow of moisture and warm advection. This is expected
to result in a day very similar to yesterday, where a lull of sorts
happens between roughly daybreak and the late morning because of
extensive debris cloudiness. No reason to think that we wouldn`t
destabilize by the afternoon, with perhaps upwards of 2000 J/kg
of sfc-based CAPE east of the mtns and 20 kt or so of deep layer
shear to push storms along and loosely organize them into broken
lines and clusters. RAP profiles show better lapse rates compared
to yesterday, but continued deep moisture and not much dCAPE,
so severe weather is unlikely. That being said, at least one run
of the HRRR shows a line coming northeast out of Georgia that
would be interesting this evening. Isolated flash flooding still
is probably the bigger threat. Problem is...the CAMs show little
coverage to speak of thru the bulk of the day, so precip probs were
actually cut back thru the afternoon. The convection will persist
into the overnight hours and slowly diminish toward daybreak once
again.Temps will be similar to yesterday.

&&

.SHORT TERM /SUNDAY THROUGH TUESDAY/...
As of 234 AM EDT Saturday...

Key Messages:

1) Afternoon showers and thunderstorms expected Sunday and Monday,
with low risk of severe weather.

2) Muggy and increasingly hot conditions expected early next week.

No major change to the thinking for the latter half of the weekend.
With a Bermuda High still in place across the western Atlantic,
diurnal showers and thunder are expecterd.  A deamplifying z500
trough axis will glide across the Ohio Valley on Sunday, providing
a modest uptick in synoptic forcing and lending a little extra
vigor to afternoon convection...with somewhat better coverage still
expected on Sunday compared to earlier in the weekend.  Lapse rates
still look less-than-favorable for severe weather...so sbCAPE will
struggle to creep above 1200 J/kg, and the bigger issue still looks
like isolated hydro issues where convection drives up rain rates.

On Monday, the Bermuda High will begin to retrograde
ever-so-slightly westward.  This doesn`t look like it`ll have
too much effect on the rain/thunder forecast through the end of
the short term...other than shifting the axis of best PWs a little
west of our CWA, and perhaps curtailing overall coverage courtesy of
weaker low-level moisture flux.  Nonetheless, ensembles depict solid
90th percentile PWs, especially across the NC mountains...so expect
another round of diurnal convection Monday.  And, as thicknesses
begin to increase, Monday should be the first day of what will
wind up being a weeklong warming trend...with highs expected to
be 1-2 categories above normal.

&&

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
As of 256 AM EDT Saturday...

Key Messages:

1) Seasonal rain and thunder chances continue through Wednesday.

2) A weak cold front crosses the area Thursday night, resulting
in some limited drying.

3) Warming temperatures continue, and should be well above normal
Wednesday and beyond.

Unsettled weather will continue for much of the extended forecast
period.  Through at least Thursday, there`ll be little change in the
synoptic pattern...which is to say subtropical ridging will remain
in place and low-level moisture flux will continue, if perhaps
weakening Wednesday and beyond as the Bermuda High expands westward
and forces low-level winds to become more westerly.  Expect diurnal
showers and thunderstorms, with low-end severe risk...but at least
some concern for hydro issues...through Wednesday.

Wednesday night, a z500 trough will eject out of the northern
Great Plains, quickly crossing the Midwest and entering the
Ohio Valley on Thursday.  Operational guidance is in marginally
better agreement than earlier forecasts on the surface front`s
arrival in the Carolinas late Thursday evening or overnight...but
long-range ensemble solutions still depict significant variance in
timing...with some solutions bringing the front in early enough
Thursday for an elevated convective risk and others bringing it
in as late as the diurnal minimum Friday morning.

In any case, the front will bring in some slightly drier air, but
won`t be strong enough to really dislodge the Bermuda High...which
guidance depicts maintaining its strength if perhaps retreating
eastward a bit.  At best, it appears all we can expect is a lull
in afternoon showers for a day or so...and little if any relief
from unseasonably warm temperatures, which by the end of the period
may climb into the low- to mid-90s.

&&

.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
At KCLT and elsewhere: Once again...a total mixed bag of variable
ceilings at daybreak, with the main concern being a LIFR stratus
deck to the south of KCLT making a run. This will be coming up
against the timing of the warming boundary layer, so instead of
advecting the LIFR/IFR restriction up from the south, we will
probably see the development of an MVFR stratocu deck as the
boundary layer warms up and convection develops. Unfortunately,
the realing might be more like anything goes. Similar to yesterday,
there should be a lull through the diurnal minimum, then scattered
storms will develop from midday onward. Will handle with PROB30s
for now. Tonight will be another round of mostly nocturnal
deep convection with some organization suggested by the model
guidance. More restrictions are likely late tonight and early
Sunday.

Outlook: Showers and thunderstorms are expected at any time thru
early next week. Late night and early morning fog and low stratus
restrictions will be possible each day.

&&

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

&&

$$

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