Severe Thunderstorm Warning 337, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
802 PM EDT Sat Aug 26 2023

.SYNOPSIS...
Lingering showers and thunderstorms possible through midnight
tonight. A frontal boundary will bring cooler temperatures below
normal through the period. Heavy rainfall likely Sunday through
Tuesday. Mid to late week weather remains uncertain due to the
potential for a tropical system to develop Gulf of Mexico.

&&

.NEAR TERM /THROUGH SUNDAY/...
As of 745 PM Saturday: A few showers and storms developed in the CLT
Metro, but most of the heavier activity has resided outside of the
CWA. Still can't rule out lingering showers and thunderstorms with
an under worked environment. Some of the CAMS do just that through
around midnight, mainly in the NC Piedmont. Kept lingering PoPs as a
result across a good portion of the CFWA. Otherwise, the overnight
looks drier than previously advertised and tweaked the forecast
based on trends and current observations.

The boundary should settle to the south of the CWA by Sunday,
bringing in cooler temps. Meanwhile, the upper ridge begins to
retrograde westward, allowing for upper flow to move southward from
the upper Great Lakes. This developing trough will swing through the
area with another boundary that should stall just to the south of
the region on Sunday morning. More S/SE surface and mid-level flow
should draw in additional moisture, setting the stage for a wetter
pattern from the end of this forecast period into the next. At this
point, showers and thunderstorms are likely Sunday afternoon, after
2PM. The enviroment remains primed to support widespread showers and
thunderstorms with 2000 J/kg of SBCAPE, PWATS approaching 2.5
inches, and an enhanced are of DPVA embedded within the trough.
Therefore, categorical PoPs across the NC Mountains and widespread
through the NC/SC Piedmonts. Confidence is increasing on heavy
rainfall with local impacts of isolated flooding, especially in
urban areas for Sunday. Again, this event will stretch beyond
Sunday, into the work week, with additional rainfall anticipated.
Currently 2-4 inches from Saturday evening through Tuesday morning,
with totals subject to change depending on where storms form and
train. As for temperatures, expect low 90s and upper 80s for the
highs and low 70s for Saturday night.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
As of 2:25pm EDT Saturday:  Monday and Tuesday will see mostly
cloudy conditions and continued height falls, leading to highs in
the mid 80s most areas to upper 70s in the higher terrain areas.
Dewpoints will remain strong, though, so morning lows will still be
5 or more degrees above normal.  Broad trough will persist over the
eastern CONUS with numerous shortwaves transiting the region that
will help to realize the 2" plus PWAT values Monday and Tuesday
afternoons. Overall synoptic forcing is on the weak side as most
energy with the trough is well north, leading to a strong diurnal
signal in convection, as well as light surface winds.  Shear will be
weak as well, topping out at 25kts on Monday and Tuesday.  CAPE is
likewise underwhelming with model soundings showing SBCAPE around
1000 j/kg. Severe weather is, thus, not a huge concern with short-
lived cells the dominant mode.

Total rain through Tuesday might average around 2", which by itself
will not trigger major hydro concerns, but this will serve to
saturate the surface, setting things up for more sensitive runoff
potential later in the week.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 2:45pm EDT Saturday:  Extended forecast will be largely
determined by large uncertainty regarding potential Gulf tropical
system.  NHC has a large chance of a tropical system forming in the
Eastern Gulf over the next couple of days, but  models vary quite a
bit on the path of this potential system.  GFS persists in putting
the storm much further north than other models, with  possibly heavy
rain Wednesday night into Friday, while EC and Canadian models have
the system tracking more along the coast with potentially very
limited rainfall inland.  Models tend to agree, though, that once
this tropical system is past, POP declines considerably.  Hydro
concerns remain an area to watch as moderate precipitation earlier
in the weak will create antecedent conditions for significant hydro
concerns, should something like the GFS precipitation forecast
verifies.

Continued cloudy and rainy conditions through the extended will
limit temps with highs down into the 70s, rebounding on Saturday as
trough/tropical system passes and a mid-level ridge replaces it.
Depending on path of tropical system, winds could be elevated with
its passage, particularly on Thursday.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
At KCLT and elsewhere: Mostly VFR conditions at all terminals
through Sunday morning. A few lingering showers and thunderstorms
through midnight has allowed for a VCSH/VCTS mention in the
prevailing for KCLT, and the Upstate terminals. Mountain valley
fog/low stratus can't be ruled out and gave KAVL a mention for
possible restrictions, but confidence is not as high that fog/low
stratus will work that far into the French Broad Valley. The RAP has
shown a deck of low stratus developing in the CLT Metro, where most
of the rain in the CFWA has fallen this afternoon. Confidence was
too low for a mention, but definitely worth a blurb on the AFD.
Otherwise, a cold front will sag into the area from the north and
stall in the Upstate. This will result numerous showers and
thunderstorms across the area starting Sunday afternoon. Tried to
depict the onset time and associated restrictions with a PROB30,
followed by a -SHRA VCTS prevailing line through the end of the
forecast period. Model guidance continue to produce lingering
showers and embedded thunderstorms over the terminals into Sunday
night.

Outlook: Shower and thunderstorm chances continue Sunday into early
next week as a cold front remains stalled south and east of the
forecast area. Mountain valley fog and low stratus development will
remain possible each morning around daybreak.

&&

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

&&

SYNOPSIS...CAC/CP
NEAR TERM...CAC/CP
SHORT TERM...WJM
LONG TERM...WJM
AVIATION...CAC

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
808 PM EDT Sat Aug 26 2023

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ008>014-019-101>109-280015-
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-Cherokee-York-
Anderson-Abbeville-Laurens-Union SC-Chester-Greenwood-
Oconee Mountains-Pickens Mountains-Greenville Mountains-
Greater Oconee-Greater Pickens-Central Greenville-
Southern Greenville-Northern Spartanburg-Southern Spartanburg-
808 PM EDT Sat Aug 26 2023

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

.DAY ONE...Tonight.

Isolated showers and thunderstorms possible through midnight. The
primary threats will be cloud-to-ground lightning, gusty winds, and
locally heavy rainfall.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

More numerous showers and embedded thunderstorms, with locally heavy
rainfall, will develop Sunday through Tuesday. Isolated flooding
will be possible each day in areas affected by multiple rounds of
showers and storms.

.SPOTTER INFORMATION STATEMENT...

None.

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
410 PM EDT Sat Aug 26 2023

SCZ014-262045-
Chester SC-
410 PM EDT Sat Aug 26 2023

...A strong thunderstorm will impact portions of eastern Chester
County through 445 PM EDT...

At 410 PM EDT, Doppler radar was tracking a strong thunderstorm 6
miles east of Chester, or 5 miles west of Richburg, moving southeast
at 10 mph.

HAZARD...Wind gusts up to 50 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Chester, Richburg, Blackstock, Fishing Creek Reservoir, Fort Lawn,
Cornwell and Edgemoor.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3460 8089 3455 8106 3456 8118 3475 8123
      3482 8105 3482 8097 3466 8088 3464 8090
      3462 8089
TIME...MOT...LOC 2010Z 334DEG 7KT 3473 8111

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

RWH

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
745 PM EDT Sat Aug 26 2023

NCZ071-072-270015-
Cabarrus NC-Mecklenburg NC-
745 PM EDT Sat Aug 26 2023

...A strong thunderstorm will impact portions of central Cabarrus and
east central Mecklenburg Counties through 815 PM EDT...

At 745 PM EDT, Doppler radar was tracking a strong thunderstorm 6
miles southwest of Downtown Concord, or over Charlotte Motor
Speedway, moving southeast at 10 mph.

HAZARD...Wind gusts up to 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Downtown Concord, Northeast Charlotte, East Charlotte, West Concord,
Mint Hill, Harrisburg, University City, Reedy Creek Park, Charlotte
Motor Speedway and Hidden Valley.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3525 8046 3514 8074 3536 8081 3545 8061
      3527 8045
TIME...MOT...LOC 2345Z 334DEG 7KT 3535 8068

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

RWH

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
756 PM EDT Sat Aug 26 2023

NCZ036-037-270030-
Davie NC-Iredell NC-
756 PM EDT Sat Aug 26 2023

...A strong thunderstorm will impact portions of Davie and
northeastern Iredell Counties through 830 PM EDT...

At 756 PM EDT, Doppler radar was tracking a strong thunderstorm 6
miles southeast of Yadkinville, or near Courtney, moving east at 30
mph.

HAZARD...Wind gusts up to 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Mocksville, Bermuda Run, Harmony, Fork Church, Advance, Sheffield,
Farmington and Union Grove.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3589 8040 3588 8042 3586 8039 3584 8039
      3585 8042 3583 8043 3583 8046 3584 8047
      3584 8048 3582 8047 3599 8088 3605 8083
      3604 8049 3606 8046 3601 8042 3599 8042
      3596 8038 3589 8037
TIME...MOT...LOC 2356Z 291DEG 26KT 3604 8061

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

RWH

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
826 PM EDT Sat Aug 26 2023

NCZ036-056-270100-
Iredell NC-Catawba NC-
826 PM EDT Sat Aug 26 2023

...A strong thunderstorm will impact portions of eastern Catawba and
west central Iredell Counties through 900 PM EDT...

At 826 PM EDT, Doppler radar was tracking a strong thunderstorm 6
miles northeast of Newton, or near Claremont, moving southeast at 15
mph.

HAZARD...Wind gusts up to 50 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Newton, Statesville, Conover, Claremont, Catawba, Lookout Shoals
Lake, Lake Norman State Park, St. Stephens, Lake Norman and Sherrills
Ford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3581 8114 3580 8113 3579 8113 3578 8111
      3580 8108 3581 8108 3583 8106 3577 8087
      3555 8103 3555 8107 3571 8129 3582 8121
      3582 8119 3583 8114
TIME...MOT...LOC 0026Z 300DEG 11KT 3575 8116

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

RWH

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
828 PM EDT Sat Aug 26 2023

NCZ037-270100-
Davie NC-
828 PM EDT Sat Aug 26 2023

...A strong thunderstorm will impact portions of Davie County through
900 PM EDT...

At 828 PM EDT, Doppler radar was tracking a strong thunderstorm 5
miles north of Mocksville, or 5 miles west of Bermuda Run, moving
southeast at 15 mph.

HAZARD...Wind gusts up to 50 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Mocksville, Bermuda Run, Cooleemee, Fork Church, Advance, Sheffield
and Farmington.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3588 8042 3586 8039 3584 8039 3585 8042
      3583 8043 3583 8046 3584 8047 3584 8048
      3581 8047 3579 8048 3576 8046 3591 8070
      3594 8070 3605 8062 3604 8049 3606 8046
      3601 8042 3599 8042 3596 8038 3589 8037
TIME...MOT...LOC 0028Z 312DEG 13KT 3597 8052

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

RWH