Severe Thunderstorm Warning 29, NWS Greenville-Spartanburg, SC

287 
WWUS52 KGSP 031939
SVSGSP

Severe Weather Statement
National Weather Service Greenville-Spartanburg SC
339 PM EDT Mon May 3 2021

SCC047-032000-
/O.CON.KGSP.SV.W.0029.000000T0000Z-210503T2000Z/
Greenwood SC-
339 PM EDT Mon May 3 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 PM EDT
FOR SOUTHEASTERN GREENWOOD COUNTY...

At 339 PM EDT, a severe thunderstorm was located 15 miles southeast
of Greenwood, or 8 miles south of Ninety Six Historic Site, moving
east at 20 mph.

HAZARD...Ping pong ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to trees and power lines.

Locations impacted include...
Kirksey.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 700 PM EDT for Upstate South
Carolina.

Scattered trees and power lines will be blown down in the warned
area. Seek shelter inside an interior room.

Please report damaging winds, hail, or flooding to the National
Weather Service Greenville-Spartanburg by calling toll free, 1, 800,
2 6 7, 8 1 0 1, or by posting on our Facebook page, or Tweet it using
hashtag nwsgsp. Your message should describe the event and the
specific location where it occurred.

&&

LAT...LON 3398 8205 3398 8208 3405 8206 3405 8194
      3403 8195 3400 8199 3397 8201 3396 8205
TIME...MOT...LOC 1939Z 266DEG 17KT 3402 8197 

HAIL...1.50IN
WIND...60MPH
 
$$

KRENTZ

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
254 PM EDT Mon May 3 2021

.SYNOPSIS...
Expect numerous showers and thunderstorms again on Tuesday...
a few of them severe...in a humid and unstable airmass as a cold
front approaches from the west. The front should move across the
region on Wednesday. We may dry out temporarily on Thursday as high
pressure moves past to our north.  Another active weather system
arrives early next week.

&&

.NEAR TERM /THROUGH TUESDAY/...
As of 210 pm: Widespread showers, with leading strong to
severe/potentially tornadic convection along the leading edge, has
become confined to the SE half of the CWA this afternoon. By far the
greatest potential for severe weather over the next several hours
will exist across the southern tier of zones...from Elberton GA to
Monroe NC and vicinity, where sbCAPE has crept into the 1000-1500
J/kg range and shear parameters remain more than adequate for severe
storms/isolated tornadoes. A Tornado Watch remains in effect for
this area until 7 pm EDT.

North of the Watch, widespread rain has limited insolation and
inhibited destabilization, and with the deep layer forcing shifting
north and east of the area, severe storms are looking increasingly
unlikely. One potential exception later this afternoon into the
evening will be across northwest NC, as cells are developing across
the Great Valley of east TN and moving east toward the southern
Appalachians. These will pose a threat of isolated damaging winds
across the NC border counties during that time frame.

Otherwise, a lull in convective activity is expected for much of the
area this evening. However, we will have to keep a close eye on the
somewhat messy convective picture that is expected to evolve across
the Ohio Valley and mid-Miss Valley later today. In general, the
latest convection allowing model guidance agree in sending organized
convection toward the southern Appalachians late tonight/early
Tuesday, but they are all over the place in terms of timing. If this
does happen, it will have potentially significant impacts on
convective trends for the daylight hours Tuesday. Short term model
guidance actually allows the elevated mixed layer to develop into
the region tonight into tomorrow, with mid-level lapse rates of 7
C/km depicted. This will create the potential for strong
destabilization to occur, but again, this could potentially be
disrupted by any morning convective activity and/or cirrus
debris/cool outflow originating from upstream convection. That's all
to say that forecast confidence is lower than normal for tomorrow.
The latest Day 2 outlook from SPC has roughly the western half of
the area in a Slight Risk for severe convection Tuesday, and this
seems entirely reasonable for now. But that risk level could go up or
down depending upon how upstream convection evolves tonight into
tomorrow morning.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
As of 230 PM EDT Tuesday: Tuesday night, we see an approaching 500mb
trough axis swinging through the Ozarks and generating a swath of
midlevel forcing that pushes through TN overnight.  So, anticipating
PoPs from 00Z onward, ramping up as the cold frontal band approaches
and the frontal circulation generates additional low/mid-level
forcing.  All the models are suggesting good PWATs > 1" and a
morning frontal passage.  Despite this less-than-perfect timing, all
the models except the GFS still suggest that some destabilization
will occur before the front fully breaches the CWA, so especially in
the eastern tier, we should anticipate some convective activity.
ECMWF, CMC, and NAM are all confident on SBCAPE in the 1000-2000
J/kg range, and very limited CIN throughout the morning and early
afternoon.  An 850mb LLJ also bodes well for 0-3km shear in the 30-
40kt range preceding the frontal passage, so despite modest lapse
rates we may be looking at at least some convective organization.

Notably, the latest run of the NAMnest is consistent with its
depiction of an early-morning squall line developing over TN/AL and
crossing our CWA well ahead of the front.  If this were to occur, it
could limit destabilization and reduce convective chances later in
the day.

Wednesday night, the 500mb pattern flattens significantly, so we
should see relaxed weather Wednesday night and into Thursday
morning.  Another potent shortwave then digs out of the Upper Plains
and through the Ozarks.  This should be right on our heels by late
Thursday, so the uptick in forcing for ascent paired with the switch
to southerly return flow late in the day will increase PoPs Thursday
night.

Wednesday should see at- or slightly above-normal temps, dropping to
several degrees below normal by Thursday in the wake of the cold
frontal passage.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 245 PM EDT Monday: PoPs continue through Thursday night and
Friday morning, as a 500mb trough's vort max passes essentially over
the top of the CWA...based on guidance from the GFS, ECMWF, and CMC,
which are all in shockingly close agreement at this point. So,
keeping slight PoPs in the grids through the nights, tapering off
through the day on Friday.  Friday night, as the trough passes
offshore, heights begin to recover and fairly zonal flow picks up.
With this nondescript pattern persisting through the weekend, we
should be in for several days of dry, calm weather under a lazy high
pressure system, which won't depart until Sunday afternoon.  Model
behavior is increasingly chaotic past this point, but the next
chance of rain should be sometime Sunday night or early Monday, as a
cold front approaches from the west.

The calm pattern over the weekend should allow temps to creep from
slightly below-normal on Friday, to several degrees above normal by
Monday.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
At KCLT and elsewhere: Showers and storms have generally moved
southeast of the terminals, and while VCSH/VCTS are carried at most
sites through the afternoon, it would appear the convective threat
has largely passed with relatively stable air having overspread much
of the area. Therefore, generally VFR conditions are expected
through the afternoon, but wouldn't rule out an occasional MVFR cig.
With mid/upper levels drying out and low-levels remaining very much
juiced, MVFR/possibly IFR cigs will fill in across the area as early
as late evening and continuing into the daylight hours Tuesday. The
probability of convection will also increase from late morning on,
possibly related to remnant activity moving into the area from the
TN Valley. Therefore, Prob30s for TSRA will be carried during that
time. Winds will remain SW through the period, with gusts possible
during the daylight hours.

Outlook: A cold front will likely bring another round of SHRA/TSRA
to the area by Tue afternoon, with chances persisting into Wed.
Another lull in convection is expected for the end of the week.

Confidence Table...

            19-01Z        01-07Z        07-13Z        13-18Z
KCLT       High  92%     High 100%     High  86%     High  91%
KGSP       High  82%     High  91%     High  84%     High  80%
KAVL       High  98%     High  97%     Med   66%     High  93%
KHKY       High  90%     High  84%     Med   76%     High  88%
KGMU       High  88%     High  90%     High  83%     High  84%
KAND       High  91%     High  95%     High  82%     High  90%

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...JDL
SHORT TERM...MPR
LONG TERM...MPR
AVIATION...JDL

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
500 AM EDT Mon May 3 2021

GAZ010-017-018-026-028-029-NCZ068>072-082-508-510-SCZ001>014-019-
040900-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Cleveland-Lincoln-
Gaston-Mecklenburg-Cabarrus-Union NC-Greater Rutherford-Eastern Polk-
Oconee Mountains-Pickens Mountains-Greenville Mountains-
Greater Oconee-Greater Pickens-Greater Greenville-Spartanburg-
Cherokee-York-Anderson-Abbeville-Laurens-Union SC-Chester-Greenwood-
500 AM EDT Mon May 3 2021

This Hazardous Weather Outlook is for northeast Georgia, upstate
South Carolina, and the southern foothills and southern Piedmont of
North Carolina, including the Charlotte metro area.

.DAY ONE...Today and tonight.

Numerous thunderstorms are expected to develop across the region
later this morning and through the afternoon hours. Enough
instability and wind shear will be present for some of the storms to
become severe this afternoon, perhaps as a squall line that moves
east across the area along and southeast of Interstate 85. The
stronger storms will produce damaging wind gusts and hail the size
of quarters or larger. An isolated tornado will also be possible. The
thunderstorms should move away during the early part of the evening.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

A cold front approaching from the west will be the trigger for another
round of strong to severe thunderstorms during the afternoon and
evening hours on Tuesday. The storms will increase the threat for
isolated flash flooding across areas that see storms with heavy rain
on Monday. The cold front could trigger isolated severe thunderstorms
east of the mountains again on Wednesday as it crosses the region.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please relay any information about
observed severe weather to the NWS while following all local, state,
and CDC guidelines.

NCZ033-035>037-048>053-056>059-062>065-501>507-509-040900-
Avery-Alexander-Iredell-Davie-Madison-Yancey-Mitchell-Swain-Haywood-
Buncombe-Catawba-Rowan-Graham-Northern Jackson-Macon-
Southern Jackson-Transylvania-Henderson-Caldwell Mountains-
Greater Caldwell-Burke Mountains-Greater Burke-McDowell Mountains-
Eastern McDowell-Rutherford Mountains-Polk Mountains-
500 AM EDT Mon May 3 2021

This Hazardous Weather Outlook is for the mountains, northern
foothills, and northwest Piedmont of North Carolina.

.DAY ONE...Today and tonight.

Numerous thunderstorms are expected to develop across the region
later this morning and through the afternoon hours. Enough
instability and wind shear will be present for some of the storms to
become severe this afternoon. A few of the storms will become strong
enough to produce damaging wind gusts and hail the size of quarters
or larger. Any of the storms will have frequent cloud-to-ground
lightning and heavy downpours of rain. The thunderstorms should move
away during the late afternoon.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

A cold front approaching from the west will be the trigger for
another round of strong to severe thunderstorms during the afternoon
and evening hours on Tuesday. The storms will increase the threat for
isolated flash flooding across areas that see storms with heavy rain
on Monday. The cold front should move across the mountains early on
Wednesday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please relay any information about
observed severe weather to the NWS while following all local, state,
and CDC guidelines.

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
945 AM EDT Mon May 3 2021

NCZ068-070-031430-
Gaston NC-Cleveland NC-
945 AM EDT Mon May 3 2021

...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN CLEVELAND AND
CENTRAL GASTON COUNTIES UNTIL 1030 AM EDT...

At 945 AM EDT, Doppler radar was tracking a strong thunderstorm 10
miles southeast of Shelby, or near Kings Mountain, moving northeast
at 35 mph.

Locations to be impacted include...
Gastonia, Kings Mountain, Bessemer City, South Gastonia, Dallas,
Cramerton, Lowell, Ranlo, High Shoals and Crowders Mountain State
Park.

Wind gusts up to 45 mph will be possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The combination of gusty winds and saturated soil conditions will
cause scattered trees and power lines to fall. Seek shelter inside an
interior room.

&&

LAT...LON 3521 8105 3516 8134 3517 8134 3517 8145
      3524 8147 3541 8125 3541 8120
TIME...MOT...LOC 1345Z 243DEG 29KT 3522 8138

KRENTZ

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
1015 AM EDT Mon May 3 2021

NCZ069>071-031445-
Gaston NC-Lincoln NC-Mecklenburg NC-
1015 AM EDT Mon May 3 2021

...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN LINCOLN...
NORTHWESTERN MECKLENBURG AND GASTON COUNTIES UNTIL 1045 AM EDT...

At 1014 AM EDT, Doppler radar was tracking a strong thunderstorm near
Gastonia, moving northeast at 30 mph.

Locations to be impacted include...
Gastonia, Uptown Charlotte, Huntersville, Northeast Charlotte,
Northwest Charlotte, Cornelius, Mt Holly, Belmont, Bessemer City and
South Gastonia.

Wind gusts up to 45 mph will be possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Gusty winds can blow down trees that are dead, or that have weakened
root systems. Outdoor furniture and similar items can be tossed
around if not anchored. Seek shelter indoors.

&&

LAT...LON 3515 8111 3516 8119 3516 8123 3529 8130
      3550 8096 3549 8094 3551 8091 3551 8087
      3526 8069
TIME...MOT...LOC 1414Z 241DEG 28KT 3524 8114

KRENTZ

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
1158 AM EDT Mon May 3 2021

NCZ056-068>070-504-508-SCZ008-009-013-031630-
Greater Rutherford NC-Gaston NC-Cleveland NC-Lincoln NC-
Greater Burke NC-Catawba NC-York SC-Cherokee SC-Union SC-
1158 AM EDT Mon May 3 2021

...A CLUSTER OF THUNDERSTORMS WILL IMPACT SOUTHWESTERN CATAWBA...
NORTHEASTERN RUTHERFORD...WESTERN LINCOLN...CLEVELAND...WESTERN
GASTON...SOUTHEASTERN BURKE...NORTHWESTERN YORK...EASTERN CHEROKEE
AND NORTH CENTRAL UNION COUNTIES UNTIL 1230 PM EDT...

At 1158 AM EDT, Doppler radar indicated the leading edge of a cluster
of thunderstorms along a line extending from near Forest City to 6
miles north of Gaffney to 11 miles southwest of Union, and moving
northeast at 35 mph.

Locations to be impacted include...
Shelby, Lincolnton, Union, Gastonia, Kings Mountain, Cherryville,
Bessemer City, Valdese, Icard and Blacksburg.

Wind gusts up to 45 mph will be possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Gusty winds can blow down trees that are dead, or that have weakened
root systems. Outdoor furniture and similar items can be tossed
around if not anchored. Seek shelter indoors.

&&

LAT...LON 3551 8121 3508 8125 3465 8174 3520 8157
      3549 8182 3578 8155 3578 8147
TIME...MOT...LOC 1558Z 222DEG 29KT 3535 8186 3516 8163 3464 8180

KRENTZ

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
1224 PM EDT Mon May 3 2021

NCZ035-056-068>071-502-504-SCZ008-031715-
Gaston NC-Cleveland NC-Lincoln NC-Greater Burke NC-
Greater Caldwell NC-Mecklenburg NC-Alexander NC-Catawba NC-
Cherokee SC-
1224 PM EDT Mon May 3 2021

...A CLUSTER OF THUNDERSTORMS WILL IMPACT CATAWBA...SOUTHWESTERN
ALEXANDER...LINCOLN...SOUTHEASTERN CALDWELL...NORTHWESTERN
MECKLENBURG...SOUTHEASTERN CLEVELAND...GASTON...SOUTHEASTERN BURKE
AND NORTHEASTERN CHEROKEE COUNTIES UNTIL 115 PM EDT...

At 1224 PM EDT, Doppler radar indicated the leading edge of a cluster
of thunderstorms along a line extending from 11 miles southwest of
Hickory to near Lincolnton to 11 miles southeast of Shelby, and
moving northeast at 30 mph.

Locations to be impacted include...
Gastonia, Hickory, Newton, Lincolnton, Taylorsville, Huntersville,
Kings Mountain, St. Stephens, Conover and Cherryville.

Wind gusts up to 45 mph will be possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Gusty winds can blow down trees that are dead, or that have weakened
root systems. Outdoor furniture and similar items can be tossed
around if not anchored. Seek shelter indoors.

&&

LAT...LON 3594 8118 3579 8110 3578 8111 3574 8107
      3553 8095 3550 8096 3550 8093 3542 8089
      3516 8132 3517 8137 3511 8140 3508 8146
      3543 8137 3572 8161
TIME...MOT...LOC 1624Z 223DEG 25KT 3565 8150 3549 8129 3515 8141

KRENTZ

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
110 PM EDT Mon May 3 2021

NCZ070>072-082-031800-
Gaston NC-Union NC-Cabarrus NC-Mecklenburg NC-
110 PM EDT Mon May 3 2021

...A CLUSTER OF THUNDERSTORMS WILL IMPACT CABARRUS...MECKLENBURG...
SOUTHEASTERN GASTON AND NORTH CENTRAL UNION COUNTIES UNTIL 200 PM
EDT...

At 110 PM EDT, Doppler radar indicated the leading edge of a cluster
of thunderstorms along a line extending from 8 miles east of Gastonia
to 11 miles north of Rock Hill, and moving east at 45 mph.

Locations to be impacted include... Charlotte, Concord and Matthews.

Wind gusts up to 40 mph and pea size hail will be possible in these
areas.

Doppler radar indicates weak rotation with these storms. Spin-up of a
very brief, weak tornado cannot be ruled out. Be prepared to take
immediate action if a tornado is sighted or a Tornado Warning is
issued.

LAT...LON 3507 8091 3511 8094 3506 8100 3506 8105
      3510 8105 3511 8103 3513 8105 3527 8104
      3550 8050 3550 8046 3549 8046 3527 8045
      3519 8051 3518 8050 3516 8044 3512 8044
TIME...MOT...LOC 1710Z 249DEG 39KT 3521 8104 3511 8103

8

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
125 PM EDT Mon May 3 2021

GAZ029-031800-
Elbert GA-
125 PM EDT Mon May 3 2021

...A STRONG THUNDERSTORM WILL IMPACT ELBERT COUNTY UNTIL 200 PM
EDT...

At 125 PM EDT, Doppler radar was tracking a strong thunderstorm 10
miles west of Elberton, or 5 miles north of Carlton, moving east at
30 mph.

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

Wind gusts up to 50 mph will be possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The combination of gusty winds and saturated soil conditions will
cause scattered trees and power lines to fall. Seek shelter inside an
interior room.

Doppler radar indicates weak rotation with this storm. Spin-up of a
very brief, weak tornado cannot be ruled out. Be prepared to take
immediate action if a tornado is sighted or a Tornado Warning is
issued.

&&

A Tornado Watch remains in effect until 700 PM EDT for northeastern
Georgia...and Upstate South Carolina.

LAT...LON 3404 8295 3404 8298 3408 8300 3410 8304
      3411 8303 3412 8305 3415 8306 3417 8310
      3429 8277 3427 8275 3418 8273 3415 8272
      3413 8267 3410 8265 3404 8264 3403 8294
TIME...MOT...LOC 1725Z 259DEG 26KT 3412 8304

8