Severe Thunderstorm Warning 321, NWS Greenville-Spartanburg, SC

699 
WWUS52 KGSP 310723
SVSGSP

Severe Weather Statement
National Weather Service Greenville-Spartanburg SC
323 AM EDT Mon Aug 31 2020

NCC035-045-109-310733-
/O.EXP.KGSP.SV.W.0321.000000T0000Z-200831T0730Z/
Catawba NC-Lincoln NC-Cleveland NC-
323 AM EDT Mon Aug 31 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN CATAWBA...WESTERN
LINCOLN AND NORTH CENTRAL CLEVELAND COUNTIES WILL EXPIRE AT 330 AM
EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning will be allowed to expire.  However gusty winds
are still possible with this thunderstorm.

LAT...LON 3567 8137 3549 8119 3542 8143 3542 8145
      3541 8145 3540 8148 3550 8158
TIME...MOT...LOC 0723Z 237DEG 18KT 3554 8136 

$$

RM

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
159 AM EDT Mon Aug 31 2020

.SYNOPSIS...
The Bermuda High building into the area will largely limit afternoon
to evening thunderstorms by mid-week and produce seasonably hot
conditions that will last through the end of the work week.
Unsettled and cooler weather may return by this weekend.

&&

.NEAR TERM /THROUGH TODAY/...
As of 143 AM Monday: A cluster of convection continues to push
northeast across the middle of the fcst area. Instability is
not that great, but an axis of 500-1000 J/kg of sfc-based CAPE
extends ahead to the northeast up into SW Virginia, and it appears
this activity will continue to run up in that direction as it is
driven forth by a weak low level jet. The steady movement will
cut back on the flash flood potential, but will contribute to
occasional wind gusts up to around 30 mph. A weak warm front will
continue to drift NEWD thru the area, bringing a plume of 1.75-2.0"
PWATs along with elevated instability (showalter index of -2 to
-5 C). The cluster of convection may be sustained by some upper
divergence and DPVA, as a embedded shortwave trough ripples thru
flat flow aloft. Precip probs have been significantly raised to
account for the radar trends. Confidence is too low on anything
more than isolated flooding to warrant a Flash Flood Watch. Temps
will remain above normal overnight under increasing clouds.

While convective coverage is forecast to diminish late tonight
into Monday morning, any lull should be brief, as convection
should blossom across the area Monday afternoon in light of
continued rounds of height falls and persistence of deep moisture
plume characterized by precipitable water values of around 2
inches. Morning cloud cover, showers, and deep warm cloud layers
will limit the amount of instability Mon afternoon, and the severe
storm threat, while non-zero will continue to take a back seat to
hydro concerns.  While the accelerating mid-level flow should allow
for somewhat swift cell movement, conditions will be favorable
for training of efficient rainfall-producing cells, especially in
and around terrain features, and along weak E/W-oriented surface
boundary. Speaking of which, max temps Monday will be very tricky,
as some operational guidance is suggesting development of a weak
in-situ cold air damming signature, although if/when/where this
sets up is very much in doubt. Even so, max temps should be at
least a couple of degrees below climo in most areas.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
As of 1215 AM Monday: The main story Tuesday through Thursday night
will be the building heat. A rather stagnant pattern will be in
place Tuesday through Thursday night as a nearly stationary Bermuda
High pinwheels off the Southeast coast. Weak shortwave energy
passing to the north will largely not affect apparent weather in our
area as long as we are under the protection of the Bermuda high.
Showers and thunderstorms and associated cloud cover will decrease
in coverage and become more diurnally focused as any lingering wedge
or boundaries and associated upglide dissipates Tuesday with the
ridge dominating the weather Wednesday and Thursday. High
temperatures will respond in kind with widespread highs in the low to
mid 90s outside of the mountains and peak heat index values near 100
for portions of the I-85 corridor and points south.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
As of 1245 AM Monday...A progressive polar jet with embedded energy
associated with a trough over the Great Lakes will finally begin to
break down the Bermuda High this weekend. A 1025 continental high
pressure system on the heals of a weak cold front will press from
the mid-Mississippi Valley into the Mid-Atlantic by this weekend,
likely providing enough oomph to push the boundary at least into the
forecast area. A separate frontal boundary near the Gulf Coast may
active towards southern areas, providing additional lift and
moisture over the feature as well as a short-lived wedge that may
take shape as the surface high presses offshore. The net result is
increases showers and thunderstorms with the initial front late
Friday, continued into the weekend with less in the way of thunder
owing to the extensive cloud cover and retreating wedge. One more
hot day is likely Friday, especially east of the mountains, before
temperatures tumble to near to below normal over the weekend.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
At KCLT and elsewhere: We will continue to deal with an area
of showers and thunderstorms pressing northeastward across the
western Carolinas through the pre-dawn hours, driven forth by
a weak warm front and low level jet. Brief MVFR restrictions in
showers and thunderstorms can be expected as it passes. In its wake,
the guidance continues to favor the development of low stratus in
the pre-dawn hours, dropping down through the MVFR category and
settling into IFR at daybreak. Confidence is better to the west
where some IFR-level clouds are noted upstream across north GA,
but not as good toward KCLT. The IFR was included in a TEMPO at
the Upstate TAF sites, but will take a wait-and-see approach to
KCLT for the time being. After this activity moves out, we could
be in something of a lull for the better part of the day outside
of the nrn foothills/NW Piedmont. Prefer to hold onto my PROB and
TEMPO for the better chances of storms in the late afternoon and
evening hours even though showers cannot be ruled out at any time
during the day. The ceiling restriction should gradually lift and
scatter during the middle part of the day, with VFR after that
outside of storms. Wind direction will be all over the place,
but mainly E/SE for most of the day. This evening, another round
of showers and thunderstorms is expected, particularly over the
NC part of the fcst area. This will be handled with PROB30s for
the time being. We will add more detail in the next issuance.

Outlook: More typical coverage of diurnal showers/storms is expected
Tuesday into late week. Early morning low cloud/fog restrictions
will also be possible over the mountain valleys most days.

Confidence Table...

            06-12Z        12-18Z        18-24Z        00-06Z
KCLT       High  95%     High  87%     High  99%     High  99%
KGSP       High  95%     High  85%     High  97%     High  97%
KAVL       Low   52%     Med   76%     High  93%     High  89%
KHKY       High  83%     High  88%     High  83%     High  89%
KGMU       High  95%     High  82%     High  98%     High  96%
KAND       High  90%     Med   78%     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...CSH
NEAR TERM...ARK/JDL/PM
SHORT TERM...CSH
LONG TERM...CSH
AVIATION...PM

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
843 PM EDT Sun Aug 30 2020

GAZ010-017-018-026-028-029-NCZ051-052-058-059-062>064-SCZ001-002-004-
005-010-011-019-010045-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Swain-Haywood-Graham-
Northern Jackson-Macon-Southern Jackson-Transylvania-
Oconee Mountains-Pickens Mountains-Greater Oconee-Greater Pickens-
Anderson-Abbeville-Greenwood-
843 PM EDT Sun Aug 30 2020

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

.DAY ONE...Tonight.

Scattered showers and thunderstorms are expected to develop late
evening and into the overnight across southwest North Carolina,
northeast Georgia and the western Upstate. The main threat will be
cloud-to-ground lightning and heavy downpours, but one or two could
become strong enough to produce damaging wind gusts. The storms may
continue to develop through the overnight period. While the threat of
severe storms will diminish by the late evening, the potential for
localized flash flooding will increase.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Scattered to numerous thunderstorms can be expected on Monday. A few
storms may become severe, producing damaging winds, frequent
lightning, and locally heavy rainfall.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ033-035>037-048>050-053-056-057-065-068>072-082-501>510-SCZ003-
006>009-012>014-010045-
Avery-Alexander-Iredell-Davie-Madison-Yancey-Mitchell-Buncombe-
Catawba-Rowan-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-
Greenville Mountains-Greater Greenville-Spartanburg-Cherokee-York-
Laurens-Union SC-Chester-
843 PM EDT Sun Aug 30 2020

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

.DAY ONE...Tonight.

Scattered showers and thunderstorms may develop after midnight
through the pre-dawn hours Monday from southwest to Northeast across
the Upstate and western North Carolina. Cloud-to-ground lightning
and heavy downpours will be the primary threats. Localized flash
flooding cannot be ruled out.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Scattered to numerous thunderstorms can be expected on Monday. A few
storms may become severe, producing damaging winds, frequent
lightning, and locally heavy rainfall. Isolated flash flooding will
be possible.

.SPOTTER INFORMATION STATEMENT...

None.

ARK

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
1259 AM EDT Mon Aug 31 2020

NCZ053-065-505>510-SCZ003-006-007-310545-
Buncombe NC-Greater Rutherford NC-McDowell Mountains NC-Henderson NC-
Polk Mountains NC-Rutherford Mountains NC-Eastern McDowell NC-
Eastern Polk NC-Greenville Mountains SC-Spartanburg SC-
Greater Greenville SC-
1259 AM EDT Mon Aug 31 2020

...STRONG THUNDERSTORMS WILL IMPACT MCDOWELL...RUTHERFORD...EASTERN
HENDERSON...POLK...SOUTHEASTERN BUNCOMBE...NORTHEASTERN GREENVILLE
AND NORTHWESTERN SPARTANBURG COUNTIES UNTIL 145 AM EDT...

At 1258 AM EDT, Doppler radar indicated strong thunderstorms along a
line extending from 10 miles southeast of Downtown Asheville to 12
miles northeast of Greenville Downtown, and moving northeast at 30
mph.

Locations to be impacted include...
Forest City, Marion, Rutherfordton, Columbus, Hendersonville, Greer,
Black Mountain, Spindale, Landrum and Fairview In Buncombe County.

Wind gusts up to 40 mph and very heavy rainfall rates up to 1 to 2
inches per hour 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.

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 3584 8199 3518 8181 3518 8187 3513 8185
      3487 8229 3551 8252
TIME...MOT...LOC 0458Z 239DEG 25KT 3548 8243 3498 8225

HG

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
110 AM EDT Mon Aug 31 2020

SCZ007-008-012-310545-
Cherokee SC-Laurens SC-Spartanburg SC-
110 AM EDT Mon Aug 31 2020

...STRONG THUNDERSTORMS WILL IMPACT NORTH CENTRAL LAURENS...
SPARTANBURG AND SOUTHWESTERN CHEROKEE COUNTIES UNTIL 145 AM EDT...

At 109 AM EDT, Doppler radar indicated strong thunderstorms along a
line extending from 12 miles northeast of Greenville Downtown to 18
miles northwest of Laurens, and moving north at 30 mph.

Locations to be impacted include...
Spartanburg, Boiling Springs SC, Woodruff, Duncan, Lyman, Pacolet,
Cowpens, Wellford, Mayo and Roebuck.

Wind gusts up to 40 mph and very heavy rainfall rates up to 1 to 2
inches per hour 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.

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 3461 8215 3472 8218 3478 8215 3480 8217
      3480 8216 3484 8221 3494 8222 3517 8186
      3491 8171 3484 8178
TIME...MOT...LOC 0509Z 198DEG 24KT 3493 8220 3474 8215

HG

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
132 AM EDT Mon Aug 31 2020

NCZ503>508-510-SCZ007-008-310600-
Greater Rutherford NC-McDowell Mountains NC-Burke Mountains NC-
Greater Burke NC-Rutherford Mountains NC-Eastern McDowell NC-
Eastern Polk NC-Cherokee SC-Spartanburg SC-
132 AM EDT Mon Aug 31 2020

...STRONG THUNDERSTORMS WITH INTENSE LIGHTNING WILL IMPACT
MCDOWELL...RUTHERFORD...POLK...WESTERN BURKE...SPARTANBURG AND
NORTHWESTERN CHEROKEE COUNTIES UNTIL 200 AM EDT...

At 131 AM EDT, Doppler radar indicated strong thunderstorms with
intense lightning along a line extending from 14 miles southwest of
Marion to 14 miles southwest of Spartanburg, and moving northeast at
25 mph.

Locations to be impacted include...
Spartanburg, Forest City, Marion, Rutherfordton, Columbus, Boiling
Springs SC, Spindale, Duncan, Lyman and Landrum.

In addition to intense lightning, wind gusts up to 40 mph 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.

Frequent lightning is occurring with these storms. 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 storms approach.

&&

LAT...LON 3591 8182 3546 8174 3495 8180 3473 8208
      3477 8213 3537 8222 3540 8220 3540 8223
      3547 8224 3552 8223 3553 8217 3556 8225
      3559 8226
TIME...MOT...LOC 0531Z 227DEG 23KT 3555 8222 3480 8210

RM

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
200 AM EDT Mon Aug 31 2020

NCZ056-068>070-501>506-508-SCZ007-008-310645-
Caldwell Mountains NC-Cleveland NC-Lincoln NC-Greater Burke NC-
Eastern McDowell NC-Greater Rutherford NC-McDowell Mountains NC-
Gaston NC-Burke Mountains NC-Greater Caldwell NC-Catawba NC-
Cherokee SC-Spartanburg SC-
200 AM EDT Mon Aug 31 2020

...STRONG THUNDERSTORMS WITH INTENSE LIGHTNING WILL IMPACT EASTERN
MCDOWELL...SOUTHWESTERN CATAWBA...RUTHERFORD...WESTERN LINCOLN...
CENTRAL CALDWELL...CLEVELAND...NORTHWESTERN GASTON...BURKE...
NORTHEASTERN SPARTANBURG AND NORTHWESTERN CHEROKEE COUNTIES UNTIL 245
AM EDT...

At 200 AM EDT, Doppler radar indicated strong thunderstorms with
intense lightning along a line extending from 4 miles east of Spruce
Pine to 9 miles south of Forest City, and moving east at 30 mph.

Locations to be impacted include...
Shelby, Lenoir, Morganton, Forest City, Marion, Rutherfordton,
Sawmills, Valdese, Spindale and Gamewell.

In addition to intense lightning, wind gusts up to 40 mph 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 these storms. 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 storms approach.

&&

LAT...LON 3522 8135 3511 8195 3522 8197 3525 8196
      3526 8198 3585 8208 3585 8205 3587 8203
      3587 8200 3589 8198 3606 8152
TIME...MOT...LOC 0600Z 252DEG 27KT 3590 8199 3521 8189

RM

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
213 AM EDT Mon Aug 31 2020

NCZ068-504-508-310645-
Greater Rutherford NC-Cleveland NC-Greater Burke NC-
213 AM EDT Mon Aug 31 2020

...A STRONG THUNDERSTORM WITH INTENSE LIGHTNING WILL IMPACT EAST
CENTRAL RUTHERFORD...NORTHWESTERN CLEVELAND AND SOUTHEASTERN BURKE
COUNTIES UNTIL 245 AM EDT...

At 212 AM EDT, Doppler radar was tracking a strong thunderstorm with
intense lightning 7 miles northeast of Forest City, or 4 miles
northeast of Bostic, moving east at 30 mph.

Locations to be impacted include...
Forest City, Lawndale, Fallston, Polkville, Ellenboro, Bostic, Casar,
Kingstown, Belwood and South Mountains State Park.

In addition to intense lightning, wind gusts up to 50 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 3531 8184 3548 8190 3562 8158 3535 8147
TIME...MOT...LOC 0612Z 253DEG 26KT 3542 8179

RM

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
242 AM EDT Mon Aug 31 2020

NCZ056-068>070-502-504-310745-
Gaston NC-Cleveland NC-Lincoln NC-Greater Burke NC-
Greater Caldwell NC-Catawba NC-
242 AM EDT Mon Aug 31 2020

...STRONG THUNDERSTORMS WITH INTENSE LIGHTNING WILL IMPACT WESTERN
CATAWBA...WESTERN LINCOLN...SOUTHERN CALDWELL...CLEVELAND...
NORTHWESTERN GASTON AND BURKE COUNTIES UNTIL 345 AM EDT...

At 242 AM EDT, Doppler radar indicated strong thunderstorms with
intense lightning along a line extending from 3 miles northwest of
Morganton to near Shelby, and moving east at 15 mph.

Locations to be impacted include...
Hickory, Shelby, Lenoir, Morganton, Lincolnton, Gastonia, Kings
Mountain, Cherryville, Bessemer City and Longview.

In addition to intense lightning, wind gusts up to 50 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 these storms. 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 storms approach.

&&

LAT...LON 3603 8143 3526 8113 3519 8159 3548 8170
      3558 8169 3561 8175 3583 8183
TIME...MOT...LOC 0642Z 248DEG 14KT 3577 8175 3527 8156

RM