Hail in North Carolina, July 16, 2021

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
244 PM EDT Fri Jul 16 2021

.SYNOPSIS...
A broad trough of low pressure, and an associated surface cold
front, will approach from the northwest over the weekend. The
trough and front will slowly settle southeast of the area early next
week, with modest drying and cooling from the north through mid-
week. Temperatures will likely rebound later in the week.

&&

.NEAR TERM /THROUGH SATURDAY/...
As of 215 PM EDT Friday: Upper ridge that has dominated the area the
past few days is beginning to break down today as a trough and
associated front approaches the area. For this afternoon, we're
still seeing most of the convection line up along extreme southeast
zones, with mid-level capping in place elsewhere. With plentiful
moisture in place, the concern remains for isolated heavy downpours
and flash flooding, but have already seen some strong updrafts that
have led to some icy cores. Temperatures are expected to rise
another couple of degrees still this afternoon, ending up just above
normal, and with the increasing moisture ahead of the trough/front
tonight, a similar pattern tonight of above-climo temps. Pops will
remain in play especially for western zones overnight and then ramp
up quickly during the day tomorrow.

With the incoming trough, the mid-level capping will break down, but
with higher PWs, instability is actually not particularly high for
mid-July (maybe topping out at 1500 J/kg on the NAM), with no deep-
layer shear to speak of. Dynamic forcing looks better as we move
into the short term as the jet-level dynamics are still a little
farther away on Saturday to provide significant synoptic lift, but
some minimal PVA will be realized. In any event, no major concerns
for severe, though isolated strong cannot be ruled out, and the SPC
Day2 marginal to the north makes sense. Definitely more widespread
showers/thunderstorms and certainly training convection with
isolated heavy downpours leading to flash flooding concerns would be
the primary threat, and WPC marginal for the mountains lines up with
current thinking. Temperatures tomorrow will be closer to seasonal
normals.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
As of 200 PM EDT Friday: The unsettled weather pattern will continue
into the second half of the weekend with the upper trough axis
digging down into the OH Valley by Sunday with an attendant cold
front. This will provide good forcing for convective activity to
fire up late Sunday morning through the evening hours. With modest
instability and better-than-normal shear parameters, organized
convection will be possible, which could lead to a few strong to
severe thunderstorms in the CFWA on Sunday. PWAT values between
1.50"-2.00+" will introduce a hydro threat as well, especially
where any training cells develop. With the Bermuda High and trough
steadily pumping in deep layer southwesterly flow, which is parallel
to the front, will provide a higher probability of training cells.

Showers and thunderstorms should continue into Sunday night as the
trough axis and cold front starts to enter the CFWA and the slow
progression of the frontal boundary will keep the night relatively
active. Model guidance are very slow at pushing the front through
the CFWA and somewhat stalls the boundary over the CFWA during
the day Monday, which could bring another round of heavy rainfall
and a low-end severe threat, mainly for the southeastern half of
the CFWA due to the location of the boundary. Otherwise, drier
air and less forcing will start to derail categorical PoPs for
the far western and northern tiers Monday afternoon/evening, but
kept diurnal PoPs in these same areas. Temperatures will likely
run below normal for highs Sunday and Monday, while lows will be
at or slightly above normal.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 205 pm EDT Friday: The slowly developing eastern U.S. trough
will become established going into mid week as the surface cold
front is expected to stall just south of our region in mid week.
The gradual decrease in moisture and forcing across the region will
require a slow decrease in PoPs into mid week, with the
higher POPs for the southeast half of the area. Temperatures should
dip at least a category below climo given the clouds and the onset
of modest thickness falls with the fropa.

Deep-layer northwest flow should then be in place Wednesday through
Thursday. However, enough boundary layer moisture may linger over
the region for diurnal isolated to scattered convection to fire once
again. Improving insolation mid to late week should permit
temperatures to gradually rebound to climo values, with typical July
conditions likely by next Thursday. A strong shortwave should arrive
from across the Great Lakes region at the end of the week, but
timing differs among the models. The GFS is the more progressive
with that shortwave.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
At KCLT and Elsewhere: VFR to start the period with convection
developing across the Piedmont; have generally handled this with
VCSH but have TEMPO TSRA at KCLT. Will monitor other TAF sites in
case TEMPO needs to be introduced. Afternoon and evening convection
will wane overnight but a front approaching from the west will bring
convection into the mountains earlier tomorrow, spreading across the
area during the day, so PROB30 everywhere plus VCTS at KAVL toward
the end of the period. Probably typical mountain restrictions as
well but with moisture moving in and precip chances not quite going
away not as much of a typical mountain valley fog event. SW winds
generally through the period, 5-10 kt during the day and decreasing
below 5kt at night, though probably more VRB at KAVL.

Outlook: An unsettled pattern, with afternoon/evening showers and
thunderstorms and morning fog/low stratus, will persist into early
next week.

Confidence Table...

            18-24Z        00-06Z        06-12Z        12-18Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     High 100%     High  91%     High  91%
KHKY       High 100%     High 100%     High 100%     High 100%
KGMU       High 100%     High 100%     High 100%     High 100%
KAND       High 100%     High 100%     High 100%     High 100%

The percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables are available at
the following link:

www.weather.gov/gsp/aviation

&&

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

&&

SYNOPSIS...DEO
NEAR TERM...TDP
SHORT TERM...CAC
LONG TERM...DEO
AVIATION...TDP

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
400 PM EDT Fri Jul 16 2021

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-172000-
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-
400 PM EDT Fri Jul 16 2021

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

.DAY ONE...This afternoon and tonight.

Scattered showers and thunderstorms will continue to develop across
the SC Upstate and into the western Carolinas this afternoon and
evening. Any of these storms will be capable of producing gusty
winds, brief heavy downpours, and the occasional cloud- to- ground
lightning strike. Thunderstorm activity should gradually decrease
beginning around sunset.

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

Hazardous weather is not expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

MPR

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
143 PM EDT Fri Jul 16 2021

SCZ014-161815-
Chester SC-
143 PM EDT Fri Jul 16 2021

...A STRONG THUNDERSTORM WITH INTENSE LIGHTNING WILL IMPACT CENTRAL
CHESTER COUNTY UNTIL 215 PM EDT...

At 143 PM EDT, Doppler radar was tracking a strong thunderstorm with
intense lightning 5 miles south of Chester, or near Chester State
Park, moving northeast at 30 mph.

Locations to be impacted include...
Chester, Richburg, Chester State Park, Cornwell and Blackstock.

In addition to intense lightning, wind gusts up to 40 mph, pea size
hail and very heavy rainfall rates up to 2 inches per hour will be
possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent lightning is occurring with this storm. If outdoors, try to
get indoors or into a hard topped vehicle. Otherwise, stay away from
open areas and isolated high objects such as trees. When indoors,
stay away from windows and doors and avoid using wired electronic
devices. Do not take a shower or bath. Try to unplug unnecessary
appliances before the storm approaches.

&&

LAT...LON 3456 8112 3457 8129 3462 8137 3482 8119
      3482 8116 3481 8106 3470 8093
TIME...MOT...LOC 1743Z 221DEG 26KT 3462 8123

KRENTZ

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
157 PM EDT Fri Jul 16 2021

SCZ012-161830-
Laurens SC-
157 PM EDT Fri Jul 16 2021

...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN LAURENS COUNTY
UNTIL 230 PM EDT...

At 157 PM EDT, Doppler radar was tracking a strong thunderstorm 13
miles northwest of Newberry, or near Joanna, moving northeast at 10
mph.

Locations to be impacted include...
Joanna and Kinards.

Wind gusts up to 40 mph, pea size hail and very heavy rainfall rates
up to 2 inches per hour will be possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall may flood areas with poor drainage, such as
ditches and underpasses. Avoid these areas and do not cross flooded
roads. Water levels of small streams may also rise rapidly. Seek
higher ground if threatened by flood waters.

&&

LAT...LON 3436 8188 3445 8181 3455 8167 3455 8166
      3453 8165 3452 8165 3446 8170 3445 8172
      3437 8178 3435 8181 3435 8183 3433 8185
TIME...MOT...LOC 1757Z 229DEG 11KT 3438 8181

KRENTZ

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
214 PM EDT Fri Jul 16 2021

SCZ019-161845-
Greenwood SC-
214 PM EDT Fri Jul 16 2021

...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN GREENWOOD COUNTY
UNTIL 245 PM EDT...

At 213 PM EDT, Doppler radar was tracking a strong thunderstorm 13
miles southeast of Greenwood, or 5 miles south of Ninety Six Historic
Site, moving northeast at 10 mph.

Locations to be impacted include...
Ninety Six Historic Site, Kirksey, Dyson and Epworth.

Wind gusts up to 40 mph, half inch hail and very heavy rainfall rates
up to 2 inches per hour will be possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall may flood areas with poor drainage, such as
ditches and underpasses. Avoid these areas and do not cross flooded
roads. Water levels of small streams may also rise rapidly. Seek
higher ground if threatened by flood waters.

&&

LAT...LON 3398 8205 3398 8208 3399 8210 3413 8207
      3418 8192 3418 8191 3416 8191 3413 8187
      3412 8189 3410 8190 3409 8192 3404 8194
      3400 8199 3397 8201 3395 8205
TIME...MOT...LOC 1813Z 247DEG 11KT 3407 8198

KRENTZ

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
318 PM EDT Fri Jul 16 2021

GAZ029-161945-
Elbert GA-
318 PM EDT Fri Jul 16 2021

...A STRONG THUNDERSTORM WILL IMPACT CENTRAL ELBERT COUNTY UNTIL 345
PM EDT...

At 318 PM EDT, Doppler radar was tracking a strong thunderstorm near
Elberton, moving northeast at 15 mph.

Locations to be impacted include...
Elberton, Middleton, Russell State Park, Lake Russell, Sweet City,
Ruckersville, Dewy Rose and Rock Branch.

Wind gusts up to 40 mph, pea size hail and very heavy rainfall rates
up to 2 inches per hour will be possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall may flood areas with poor drainage, such as
ditches and underpasses. Avoid these areas and do not cross flooded
roads. Water levels of small streams may also rise rapidly. Seek
higher ground if threatened by flood waters.

&&

LAT...LON 3400 8290 3401 8291 3401 8294 3403 8294
      3404 8295 3404 8298 3408 8300 3408 8302
      3426 8287 3427 8284 3417 8272 3415 8272
      3414 8269 3400 8288
TIME...MOT...LOC 1918Z 228DEG 13KT 3407 8290

KRENTZ

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
733 PM EDT Fri Jul 16 2021

NCZ048-170000-
Madison NC-
733 PM EDT Fri Jul 16 2021

...A THUNDERSTORM WITH TORRENTIAL RAINFALL WILL IMPACT SOUTHWESTERN
MADISON COUNTY UNTIL 800 PM EDT...

At 733 PM EDT, Doppler radar was tracking a thunderstorm with
torrential rainfall 9 miles west of Marshall, or 5 miles south of Hot
Springs, moving northeast at 10 mph.

Locations to be impacted include...
Marshall, Hot Springs, Spring Creek, Walnut, Luck and Max Patch.

Wind gusts up to 40 mph, pea size hail and very heavy rainfall rates
up to 2 inches per hour will be possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall may flood areas with poor drainage, such as
ditches and underpasses. Avoid these areas and do not cross flooded
roads. Water levels of small streams may also rise rapidly. Seek
higher ground if threatened by flood waters.

&&

LAT...LON 3595 8285 3592 8282 3593 8280 3594 8280
      3578 8266 3569 8283 3570 8285 3568 8289
      3574 8292 3574 8295 3579 8296 3582 8295
      3584 8292 3587 8292 3588 8290 3593 8292
      3593 8290 3594 8290 3595 8287
TIME...MOT...LOC 2333Z 226DEG 8KT 3581 8285

KRENTZ