Special Weather Statement, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
244 PM EDT Sat Aug 3 2024

.SYNOPSIS...
A weak cold front will stall across the Piedmont of the Carolinas
tonight and linger through Sunday. The boundary should continue
to provide a focus for showers and thunderstorms, while cooling
temperatures back closer to average. Meanwhile, Tropical Depression
Four is forecast to track into the eastern Gulf of Mexico tonight
and will drift north toward the Florida Gulf Coast on Sunday. The
eventual track and timing of this system will determine our weather
through the middle of the week.

&&

.NEAR TERM /THROUGH SUNDAY/...
As of 147 PM EDT Saturday: It's a beautiful Saturday across the
forecast area.  Temperatures are in the upper 80s in most places,
and an extensive cu field has developed east of the NC mountains.
A few showers have already broken out over the Blue Ridge, as
a vigorous upper trough escapes the upper Ohio Valley and heads
toward Appalachia.  A surface front is now analyzed along or just
east of the NC Blue Ridge Escarpment, which looks reasonable based
on mesoanalysis data and CAM guidance.

This boundary will provide triggering for this afternoon's
convective prospects, putting the Piedmont and Upstate zones
most under the gun for active weather later.  Guidance indicates
that a plume of 2500+ J/kg sbCAPE will be in place across the
eastern third of the forecast area over the next few hours as
convection really fires up, in an environment already juiced up
with 25kts of deep shear.  As described in previous discussions,
the intrusion of dry air aloft from the western side of the front
will promote an increase in DCAPE, which is already analyzed at
800-900 J/kg over I- 77, and is only progged to increase as the
afternoon wears on, attaining a max value of 1100-1200 J/kg over
the eastern zones...more than enough to justify the Marginal/Slight
Risk for Severe Weather per SPC.  Heavy rain remains somewhat
of a concern, as steering flow will be out of the SSW, nearly
parallel to the orientation of the stalling frontal boundary.
Having said that, the dry air intrusion aloft will markedly lower
PWs compared to previous days...with even the higher end of the
12z HREF distribution only calling for 1.8-1.9".  This along
with the highly-localized nature of any hydro issues that develop
only reinforces the earlier decision to forego a Flood Watch for
this evening.  More to the point, 3- and 6-hour probability-matched
mean QPF forecasts from the morning ensembles just can't square up
with FFGs...so flood risk should remain limited.  High temperatures
will barely make it to 90 this afternoon for most locations.

Tonight, convection may linger well past sunset.  The latest
HRRR, FV3, and NSSL-WRF all depict a second wave of showers and
thunderstorms spinning up over the NC Piedmont around sundown and
pushing east of I-77 through midnight.  Once whatever festering
convection lets up, it'll be a mostly-quiet night.  Lows will
fall into the lower 70s or even 60s in some spots across the
NC Foothills and of course the mountains, and another round of
mountain valley fog and low stratus will develop before sunrise.
Some locations outside the mountains which wind up receiving a lot
of rain this afternoon may get patchy fog in the morning, too.
Tomorrow's convection remains somewhat of a question mark...as
although earlier forecasts indicated decent convective coverage,
the latest cycle of hi-res guidance has come in with a more
diffuse remnant frontal boundary than depicted prior, resulting
in less initiation Sunday afternoon and lower overall coverage.
What storms do develop will have another DCAPE-rich environment
to work with, and so will need to be watched closely.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
As of 145 PM Saturday: The short term forecast is really up in the
air, thanks to current TD 4. The latest forecast is significantly
slower with what is expected to be TS Debby. By 12z Monday, the
center is expected to be near the Big Bend area of FL, but guidance
already diverging on that, with NAM and Canadian trending west
with landfall near Apalachicola. From there, the steering flow in
the upper levels becomes weak, and Debby will slow down somewhere
over southern GA on Monday, with a general drift to the east,
possibly reaching the GA coastal waters early Tuesday. With this
track, our forecast area may actually see fairly quiet weather,
as subsidence overspreads north of the tropical circulation. With
that said, there are ensemble members that drift the low further
north before stalling, and we could see at least peripheral rain
bands from the system. Plus a stalled frontal boundary (though
washing out) may be enough to focus some deep convection, along
with the usual terrain-induced activity. Will go with the NBM PoPs
for now, but they may be overdone, given the slower motion of the
approaching tropical system. Temps will be near normal.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 230 PM Saturday: The entire medium range forecast continues
to be highly uncertain, as models are now trending toward a stalled
tropical system somewhere near coastal SC, with a possible drift
inland mid to late in the week. This could result in a prolonged
period of rain working into the forecast area from SE to NW. Even
if Debby ends up being a hurricane at its peak intensity, the
expected drift across northern FL and southern GA should weaken it,
and so the wind threat should be low, making excessive rainfall
the biggest threat. With that said, this is a relatively new trend
in the guidance, so will continue to stick close to the national
blend of models for the PoPs. The NBM has already trended higher in
PoPs and lower in max temps, which is to be expected if a remnant
tropical system ends up close to the area. Once guidance seems
to lock into a solution and confidence increases, we may see some
large shifts in the forecast either way.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
At KCLT and elsewhere: VFR conditions at all the terminals
this afternoon except KHKY, where a pesky MVFR cloud deck has
lingered well into the day.  Some showers are already spinning
up over the NC-TN border, and are progged to move east through
the afternoon hours.  All the guidance depicts some version of
this activity shifting eastward through the evening hours...with
especially numerous coverage over the I-77 corridor east of a
diffuse frontal boundary.  Multiple rounds of convection may be a
concern, especially if the latest HRRR is to be believed, as it
maintains convection well past sundown.  By midnight, the show
should be over regardless, and the mountain terminals can expect
another round of hefty flight restrictions...with the statistical
guidance as well as the NBM hitting the mountain valleys pretty
hard with IFR to LIFR ceilings again before daybreak.  Additional
convection is possible on Sunday, but coverage should be much more
sparse compared to today, and initiation may be delayed...such
that mention didn't make it into any of the 18z TAFs.

Outlook: Drier conditions will return early next week before
an unsettled and very-low-confidence pattern arrives Tuesday
and beyond.

&&

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

&&

SYNOPSIS...ARK
NEAR TERM...MPR
SHORT TERM...ARK
LONG TERM...ARK
AVIATION...MPR

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
212 PM EDT Sat Aug 3 2024

GAZ010-017-018-026-NCZ033-048>053-058-059-062>065-501-503-505-507-
509-SCZ101>105-041815-
Rabun-Habersham-Stephens-Franklin-Avery-Madison-Yancey-Mitchell-
Swain-Haywood-Buncombe-Graham-Northern Jackson-Macon-
Southern Jackson-Transylvania-Henderson-Caldwell Mountains-
Burke Mountains-McDowell Mountains-Rutherford Mountains-
Polk Mountains-Oconee Mountains-Pickens Mountains-
Greenville Mountains-Greater Oconee-Greater Pickens-
212 PM EDT Sat Aug 3 2024

This Hazardous Weather Outlook is for northeast Georgia, the
mountains of western North Carolina, and Upstate South Carolina.

.DAY ONE...This afternoon and tonight.

Scattered thunderstorms are expected across the area this afternoon
and evening. The main threats from any storm will be cloud-to-ground
lightning and torrential rainfall. A few of these storms may also
produce damaging wind gusts.

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

A tropical system may impact the western Carolinas and northeast
Georgia early next week. The track this system takes as it moves
northward will determine what impacts it may have on our area.
Check hurricanes.gov for the latest updates on this system.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ035>037-056-057-068>072-082-SCZ008-009-012>014-019-108-109-041815-
Alexander-Iredell-Davie-Catawba-Rowan-Cleveland-Lincoln-Gaston-
Mecklenburg-Cabarrus-Union NC-Cherokee-York-Laurens-Union SC-Chester-
Greenwood-Northern Spartanburg-Southern Spartanburg-
212 PM EDT Sat Aug 3 2024

...SEVERE THUNDERSTORM WATCH 592 IN EFFECT UNTIL 9 PM EDT THIS
EVENING...

This Hazardous Weather Outlook is for Piedmont North Carolina and
Upstate South Carolina.

.DAY ONE...This afternoon and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Severe Thunderstorm Watch.

In addition to the threat of severe thunderstorms, expected is torrential
rainfall that's likely to produce areas of nuisance flooding as well
as localized flash flooding. In particular, multiple storms may move
over the same location in succession, leading to a handful of hydro
issues.

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

A tropical system may impact the western Carolinas and northeast
Georgia early next week. The track this system takes as it moves
northward will determine what impacts it may have on our area.
Check hurricanes.gov for the latest updates on this system.

.SPOTTER INFORMATION STATEMENT...

Spotters are requested to forward any reports of large hail,
damaging winds, tornadoes, or flash flooding to our office.

GAZ028-029-NCZ502-504-506-508-510-SCZ010-011-106-107-041815-
Hart-Elbert-Greater Caldwell-Greater Burke-Eastern McDowell-
Greater Rutherford-Eastern Polk-Anderson-Abbeville-
Central Greenville-Southern Greenville-
212 PM EDT Sat Aug 3 2024

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

.DAY ONE...This afternoon and tonight.

Scattered to numerous thunderstorms are expected across the area
this afternoon and evening. The main threats from any storm will be
cloud-to-ground lightning and torrential rainfall that's likely to
produce areas of nuisance flooding as well as localized flash
flooding. In particular, multiple storms may move over the same
location, leading to a handful of hydro issues. In addition, some of
these storms may also produce damaging wind gusts.

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

A tropical system may impact the western Carolinas and northeast
Georgia early next week. The track this system takes as it moves
northward will determine what impacts it may have on our area.
Check hurricanes.gov for the latest updates on this system.

.SPOTTER INFORMATION STATEMENT...

Spotters are requested to forward any reports of large hail,
damaging winds, tornadoes, or flash flooding to our office.

MPR

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
130 PM EDT Sat Aug 3 2024

SCZ011-019-031815-
Abbeville SC-Greenwood SC-
130 PM EDT Sat Aug 3 2024

...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN ABBEVILLE AND
NORTHWESTERN GREENWOOD COUNTIES THROUGH 215 PM EDT...

At 130 PM EDT, Doppler radar was tracking a strong thunderstorm 6
miles southwest of Abbeville, moving northeast at 35 mph.

HAZARD...Wind gusts up to 40 mph and pea size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Greenwood, Abbeville, Calhoun Falls, Cokesbury, Hodges, Ninety Six
Historic Site, Promised Land, and Epworth.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3408 8263 3437 8223 3411 8200 3405 8232
      3406 8233 3406 8246 3408 8248 3407 8250
      3407 8253 3403 8257
TIME...MOT...LOC 1730Z 244DEG 31KT 3410 8243

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

AR

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
133 PM EDT Sat Aug 3 2024

SCZ013-014-031815-
Union SC-Chester SC-
133 PM EDT Sat Aug 3 2024

...A STRONG THUNDERSTORM WILL IMPACT SOUTHWESTERN CHESTER AND
SOUTHEASTERN UNION COUNTIES THROUGH 215 PM EDT...

At 133 PM EDT, Doppler radar was tracking a strong thunderstorm 15
miles north of VC Summer Nuclear Station, or 6 miles north of Blair,
moving northeast at 20 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 hail damage to outdoor objects is
         possible.

Locations impacted include...
Carlisle, Chester State Park, Tuckertown, Leeds, and Cornwell.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3447 8155 3449 8157 3472 8140 3463 8110
      3456 8118 3457 8142 3453 8143 3450 8142
      3449 8143 3450 8144 3449 8144 3449 8148
      3446 8153
TIME...MOT...LOC 1733Z 216DEG 19KT 3451 8140

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

AR

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
155 PM EDT Sat Aug 3 2024

NCZ082-031815-
Union NC-
155 PM EDT Sat Aug 3 2024

...A STRONG THUNDERSTORM WILL IMPACT NORTHEASTERN UNION COUNTY
THROUGH 215 PM EDT...

At 155 PM EDT, Doppler radar was tracking a strong thunderstorm 14
miles southwest of Albemarle, or 11 miles west of Ansonville, moving
northeast at 20 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 hail damage to outdoor objects is
         possible.

This storm will remain over mainly rural areas of northeastern Union
County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3508 8029 3517 8039 3518 8037 3517 8036
      3518 8033 3517 8032 3518 8032 3518 8031
      3519 8030 3519 8028
TIME...MOT...LOC 1755Z 221DEG 18KT 3517 8030

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

AR

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
247 PM EDT Sat Aug 3 2024

SCZ013-031930-
Union SC-
247 PM EDT Sat Aug 3 2024

...A STRONG THUNDERSTORM WILL IMPACT NORTHERN UNION COUNTY THROUGH
330 PM EDT...

At 247 PM EDT, Doppler radar was tracking a strong thunderstorm 8
miles west of Union, or 5 miles northwest of Buffalo, moving
northeast at 20 mph.

HAZARD...Wind gusts of 50 to 55 mph and pea size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Union, Jonesville, Buffalo, and Adamsburg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 900 PM EDT for
Upstate South Carolina.

&&

LAT...LON 3473 8181 3480 8179 3490 8165 3488 8164
      3488 8161 3489 8159 3488 8157 3477 8149
      3471 8179
TIME...MOT...LOC 1847Z 245DEG 17KT 3476 8177

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...55 MPH

AR

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
250 PM EDT Sat Aug 3 2024

NCZ082-031915-
Union NC-
250 PM EDT Sat Aug 3 2024

...A STRONG THUNDERSTORM WILL IMPACT EAST CENTRAL UNION COUNTY
THROUGH 315 PM EDT...

At 250 PM EDT, Doppler radar was tracking a strong thunderstorm 10
miles northeast of Monroe, or 4 miles north of Marshville, moving
east at 25 mph.

HAZARD...Wind gusts up to 40 mph and pea size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
New Salem.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 900 PM EDT for
the Piedmont of North Carolina.

&&

LAT...LON 3501 8030 3500 8039 3508 8045 3518 8028
TIME...MOT...LOC 1850Z 247DEG 23KT 3505 8037

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

AR

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
321 PM EDT Sat Aug 3 2024

NCZ071-072-032000-
Cabarrus NC-Mecklenburg NC-
321 PM EDT Sat Aug 3 2024

...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN CABARRUS AND
NORTHWESTERN MECKLENBURG COUNTIES THROUGH 400 PM EDT...

At 321 PM EDT, Doppler radar was tracking a strong thunderstorm 6
miles southwest of Huntersville, or 4 miles north of Northwest
Charlotte, moving northeast at 20 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...
Huntersville, Northeast Charlotte, Coddle Creek Reservoir, West
Concord, Charlotte Motor Speedway, Paw Creek, Northwest Charlotte,
Davidson, and Croft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 900 PM EDT for
the Piedmont of North Carolina.

&&

LAT...LON 3528 8096 3534 8098 3535 8097 3535 8096
      3536 8092 3537 8095 3538 8096 3536 8098
      3537 8098 3551 8078 3551 8076 3537 8064
TIME...MOT...LOC 1921Z 243DEG 19KT 3534 8092

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

AR