Damaging Wind in Georgia, August 20, 2021

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
306 PM EDT Fri Aug 20 2021

.SYNOPSIS...
Scattered showers and thunderstorms chances will continue into the
early evening hours. Subsidence aloft associated with a ridge of
high pressure over the south-central CONUS will slowly build
eastward into the Carolinas and Georgia leading to drier conditions
this weekend and early next week. The upper-level pattern will
remain relatively unchanged during this time. Isolated showers and
thunderstorms will remain possible this weekend into early next week.

&&

.NEAR TERM /THROUGH SATURDAY/...
As of 230 pm EDT: Diurnal tstm cvrg should be the greatest along and
downstream of the southern Blue Ridge escarpment where ensemble max
updrafts are progged to be more robust until early evening.  After
diurnal lessening of the deeper convection from mid-evening onward,
a fair overnight period is on tap with a smattering of locally dense
fog developing in the pre-dawn hours.  Despite broad cyclonic flow
aloft lingering atop the region through Saturday, there seems to be
no obvious sources of lift enroaching on the larger scales and in
fact PWAT is progged to notch even lower, likely further limiting
cvrg of diurnal thunderstorms.  At this point, a pretty typical late
summer Saturday is on tap, with less than climo chances for any
storms.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
As of 2:15 PM EDT Friday: Throughout the short term forecast period,
a ridge of high pressure will build across the south-central CONUS
while a closed low over the Mid-Atlantic interacts with Tropical
Storm Henri out in the western Atlantic. The ridge of high pressure
will gradually build eastward into the CWA this weekend into early
next week. As a result, the closed low will be forced northeast of
the Carolinas, gradually tracking towards New England through early
next week. This ridge of high pressure will lead near normal PWATs
and mainly NW'ly flow this weekend into Monday allowing for much
drier conditions. With no real synoptic forcing in place, daytime
heating will be the driver of diurnal showers and thunderstorms.
However, with limited moisture available across the forecast area,
only isolated showers and thunderstorms are expected throughout the
short term so capped PoPs to a slight chance to chance. High temps
should be roughly 4 to 8 degrees above Climo Sunday and Monday.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 230 PM EDT Friday: The eastern periphery of the ridge remains
over the Carolinas and Georgia at the beginning of the extended
forecast period, but retreats back west middle of next week. This
will allow the Bermuda high in the Atlantic to extend over the
southeast CONUS. So the overall synoptic pattern middle of next week
will have the Carolinas and northeast Georgia sandwiched between two
high pressure systems. This will lead to increased moisture and the
continuation of above climo high temps. PWAT values will increase
Tuesday ranging from 1.70 to 2.0 inches. These values are expected
to linger over the CWA through the end of the forecast period.
Tuesday into Wednesday shower and thunderstorm chances increase due
to a surface trough draped over the central Carolinas. This sfc
trough should remain over the Carolinas throughout the extended.
Both the GFS and ECMWF show the two ridges of high pressure working
together to bring a tropical wave into the Carolinas Thursday into
Friday. This would further increase shower and thunderstorm chances
middle to end of the workweek. Confidence on the track of this
tropical wave remains fairly low as this occurs towards the end of
the extended forecast.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
At KCLT and elsewhere: Best chances for experiencing a round of deep
convection within the mid-afternoon to early evening timeframe will
be acrs the upstate terminals and around KCLT. A tempo for TSRA will
be carried for these locales before storms ash out after 00z. A
smattering of vsby restrictions will also be carried developing
during the pre-dawn hours and for those terminals which receive a
period of rainfall today, the chances for IFR restrictions will
increase and evening fcst updates will reflect this.

Outlook: A typical, diurnal summertime convective pattern is
expected to prevail this weekend into early next week, with coverage
scattered at best. Mtn valley low stratus and fog will be possible
each morning.

&&

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

&&

SYNOPSIS...AP
NEAR TERM...CSH
SHORT TERM...AP
LONG TERM...AP
AVIATION...CSH

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
451 PM EDT Fri Aug 20 2021

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-212100-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Avery-Alexander-
Iredell-Davie-Madison-Yancey-Mitchell-Swain-Haywood-Buncombe-Catawba-
Rowan-Graham-Northern Jackson-Macon-Southern Jackson-Transylvania-
Henderson-Cleveland-Lincoln-Gaston-Mecklenburg-Cabarrus-Union NC-
Caldwell Mountains-Greater Caldwell-Burke Mountains-Greater Burke-
McDowell Mountains-Eastern McDowell-Rutherford Mountains-
Greater Rutherford-Polk Mountains-Eastern Polk-Oconee Mountains-
Pickens Mountains-Greenville Mountains-Greater Oconee-
Greater Pickens-Greater Greenville-Spartanburg-Cherokee-York-
Anderson-Abbeville-Laurens-Union SC-Chester-Greenwood-
451 PM EDT Fri Aug 20 2021

This Hazardous Weather Outlook is for northeast Georgia, piedmont
North Carolina, western North Carolina and upstate South Carolina.

.DAY ONE...Tonight.

Isolated to scattered showers and thunderstorms are expected late this
afternoon and evening. A few of these storms could become strong to severe.
The main threats from any thunderstorm will be cloud-to-ground lightning,
damaging winds, and localized flash flooding.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

JPT