Alert archive / South Carolina / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 75, NWS Greenville-Spartanburg, SC

May 4, 2020York County, South Carolina

NWS Greenville-Spartanburg, SC issued this severe thunderstorm warning at May 4, 2020, 8:56 PM EDT for York County, South Carolina. It was in force for 25 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 4, 2020, 8:56 PM EDT (00:56 UTC)
Expired
May 4, 2020, 9:21 PM EDT
In force
25 min
Issued by
NWS Greenville-Spartanburg, SC
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County York County, SC

The radar

The Greer radar (KGSP), 95 km from the middle of the area, began a volume at 01:00 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 00:00Z, 0.9 hours before the alert went out and 169 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Greensboro/Hi Pt, NC at 00:00Z on 2020-05-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Greensboro/Hi Pt, NC at 00:00Z on 2020-05-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3353 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
-10 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Greenville-Spartanburg, SC wrote its last area forecast discussion before this severe thunderstorm warning went out at May 4, 8:08 PM EDT, 48 minutes earlier.

Area forecast discussion, May 4, 8:08 PM EDT, 48 minutes before
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
808 PM EDT Mon May 4 2020

.SYNOPSIS...
A series of weak disturbances will cross the area early this week,
with showers and a few thunderstorms expected. Temperatures will
fall to below normal by Thursday, cooling off even more by the
weekend.

&&

.NEAR TERM /THROUGH TUESDAY/...
As of 510 PM Monday: The RADAR remains clear across our fcst area
as a weak cap persists around 10kft. If the cap gets eroded over
the next few hours, then we could see some showers and possibly a
few thunderstorms as moisture increases across the area.

The main concern going forward, however, is an impressive-looking
MCS currently well to our west, that is looking more likely to make
a run at our CWFA overnight (say midnight to 4 am). Guidance is
pretty all over the board to where this might occur, but thinking
if a decaying MCS makes it into our area, it would be most likely
to follow the instability gradient or roughly the I-26 corridor.
The potential for damaging wind would be the main threat with small
hail and maybe a weak and brief tornado as secondary threats
(mainly southwest of I-26). Warm front activation late tonight
will support mainly showers racing northeastward into the early
morning morning hours Tuesday.

After a lull in activity Tuesday morning, increasing instability and
a nearby shortwave energy to our north will support another round of
showers and thunderstorms focused across the mountains. An elevated
mixed layer with decent instability aloft may support some strong to
severe thunderstorms focused across the mountains with wind followed
by hail as the primary threats. Modest moisture transport from the
west and decent instability may support localized excessive rain
across the mountains Tuesday afternoon, especially if training of
cells develops. A hybrid wedge across the North Carolina Piedmont
will likely limit convection for the area especially through mid
afternoon. Rain and wedge cooled air should support lows into the
50s tonight with highs struggling to break 60 for the I-40 corridor
(thanks to the wedge) with 70s and 80s elsewhere.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
As of 230 PM Monday: With broad, low amplitude troughing aloft, sfc
low pressure along a once stationary front will be in the process of
moving through the Carolinas Tuesday night as it's associated cold
front brings showers and thunderstorms to the area. Do expect
convection to be ongoing at the beginning of the fcst period,
especially with a majority of the area situated within the warm
sector. Upper s/w impulses within troughing will aid with upper
dynamic support and notable shear looks to be in place. The amount
of available instability continues to be the fly in the ointment and
will depend on the timing of the system to push through the area.
For now, have kept with the trend of showers and thunderstorms, with
a few thunderstorms possibly becoming strong to severe Tuesday
night. The primary threat with any stronger storm would be hail and
damaging winds. With the latest update, SPC Day 2 convective outlook
has the western portions of the area under a marginal risk and the
rest of the area under a general thunder, where the atmosphere looks
to be slightly more stable. Do not anticipate any hydro threats attm.

Behind the exiting system, light showers may linger into Wednesday
late morning across the area, possibly later along the TN border
with NW flow. Otherwise, expect a drying trend for the remainder of
the fcst period into Thursday as sfc high pressure builds into the
area. Max temperatures through the period will remain below normal,
with min temperatures Wednesday morning above normal and below
normal Thursday morning.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 255 PM Monday: The aforementioned drying trend will be a brief
one as latest guidance continues to prog s/w energy within broad
upper troughing to usher in another cold front later in the day on
Friday. Conditions are trending more towards showers with this
system versus thunderstorms/severe weather, especially given limited
instability and upper dynamic support. Anticipate pre-frontal
showers across the westernmost portions of the area Friday morning,
with activity spreading east-southeastward throughout the day. As
precipitation tapers off across much of the area, with a cooler
airmass infiltrating in behind the front, could not entirely rule
out isolated snow showers at the higher elevations late Friday night
into Saturday morning with upper trough swinging through overhead.

Otherwise, Saturday and Sunday will be dry as sfc high pressure
builds in with amplified trough over the eastern CONUS. Guidance
continues to prog temperatures below normal through the forecast
period. As a result, frost/freeze concerns could arise in some
locations, as noted the past few days.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
At KCLT and Elsewhere: It's looking like a decaying MCS could very
well support another round of showers and thunderstorms between roughly
05Z and 09Z overnight that impacts most sites. A lull in activity is
expected after that, with another round of convection possible later
tomorrow aftn and evening. The combination of rainfall south and a
hybrid wedge setting up to the north will likely support MVFR or lower
cigs across many sites after 09Z with some gradual improvement likely
by the aftn.

Outlook: A period of unsettled weather and flight restrictions
continues thru Wednesday. Dry high pressure spreads back over the
region on Thursday.

Confidence Table...

            00-06Z        06-12Z        12-18Z        18-00Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     High  80%     High  89%     High 100%
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...17
NEAR TERM...JPT
SHORT TERM...12
LONG TERM...12
AVIATION...JPT
Hazardous weather outlook, May 4, 6:11 PM EDT, 2 hours 45 minutes before
Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
611 PM EDT Mon May 4 2020

GAZ010-017-018-026-028-029-NCZ048-051>053-058-059-062>065-507-509-
510-SCZ001>007-010>013-019-052215-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Madison-Swain-Haywood-
Buncombe-Graham-Northern Jackson-Macon-Southern Jackson-Transylvania-
Henderson-Rutherford Mountains-Polk Mountains-Eastern Polk-
Oconee Mountains-Pickens Mountains-Greenville Mountains-
Greater Oconee-Greater Pickens-Greater Greenville-Spartanburg-
Anderson-Abbeville-Laurens-Union SC-Greenwood-
611 PM EDT Mon May 4 2020

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

.DAY ONE...Tonight.

A line or area of strong to severe thunderstorms is expected to move
east across Tennessee this evening and reach western North Carolina
late in the evening. If the storms hold together, strong to severe
thunderstorms may move across the central and southern mountains of
North Carolina, northeast Georgia, and Upstate South Carolina through
the early morning hours. Strong and damaging wind gusts are the main
threat, but sporadic large hail or a brief tornado cannot be ruled
out. Lightning, gusty winds, and brief, heavy rainfall can be
expected with any storm. The storms would weaken as they move east
across the Upstate before dawn.

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

Hazardous weather is not expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ033-049-050-068>072-082-501-503-505-506-508-SCZ008-009-014-052215-
Avery-Yancey-Mitchell-Cleveland-Lincoln-Gaston-Mecklenburg-Cabarrus-
Union NC-Caldwell Mountains-Burke Mountains-McDowell Mountains-
Eastern McDowell-Greater Rutherford-Cherokee-York-Chester-
611 PM EDT Mon May 4 2020

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

.DAY ONE...Tonight.

Showers and a few thunderstorms will move into the area tonight.
Lightning, gusty winds, and brief, heavy rainfall can be expected
with any storm.

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

Hazardous weather is not expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ035>037-056-057-502-504-052215-
Alexander-Iredell-Davie-Catawba-Rowan-Greater Caldwell-Greater Burke-
611 PM EDT Mon May 4 2020

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

.DAY ONE...Tonight.

No hazardous weather is expected at this time.

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

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

PM

In the hours before

Local storm report, May 4, 7:12 PM EDT, 1 hour 44 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
712 PM EDT MON MAY 4 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0700 PM     HAIL             2 W TIGERVILLE          35.07N 82.41W
05/04/2020  E0.88 INCH       GREENVILLE         SC   PUBLIC

&&

MOORE
Local storm report, May 4, 8:14 PM EDT, 42 minutes before
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Local storm report, May 4, 8:18 PM EDT, 38 minutes before
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Local storm report, May 4, 8:29 PM EDT, 27 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
829 PM EDT MON MAY 4 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0748 PM     HAIL             1 S DUNCAN              34.92N 82.14W
05/04/2020  E1.75 INCH       SPARTANBURG        SC   PUBLIC

            UP TO GOLF BALL SIZED HAIL REPORTED IN THE ROGERS MILL
            NEIGHBORHOOD OF DUNCAN.

&&

JPT
Local storm report, May 4, 8:43 PM EDT, 13 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
843 PM EDT MON MAY 4 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0750 PM     HAIL             2 SSW DUNCAN            34.91N 82.15W
05/04/2020  E1.75 INCH       SPARTANBURG        SC   PUBLIC

            UP TO GOLF BALL SIZED HAIL REPORTED OVER NORTH LAKEVIEW
            DRIVE.

&&

JPT
Local storm report, May 4, 8:45 PM EDT, 11 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
845 PM EDT MON MAY 4 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0756 PM     HAIL             REIDVILLE               34.86N 82.11W
05/04/2020  E1.00 INCH       SPARTANBURG        SC   TRAINED SPOTTER

            1 INCH HAIL REPORTED AT THE INTERSECTION OF HWY 290 AND
            REIDVILLE RD.

&&

JPT

The office that day

Everything else NWS Greenville-Spartanburg, SC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 4, 11:14 PM EDTSpecial Weather StatementGSPUnion31 min
May 4, 11:43 PM EDTSpecial Weather StatementGSPUnion32 min
May 5, 3:22 AM EDTSevere Thunderstorm WarningGSPCleveland, Gaston38 min
May 5, 3:57 AM EDTSevere Thunderstorm WarningGSPMecklenburg, Union48 min
May 5, 4:33 AM EDTSevere Thunderstorm WarningGSPMecklenburg, Union27 min
May 5, 3:17 PM EDTSpecial Weather StatementGSPGraham28 min
May 5, 3:27 PM EDTSevere Thunderstorm WarningGSPGraham, Macon, Swain28 min
May 5, 3:52 PM EDTSevere Thunderstorm WarningGSPJackson, Macon, Transylvania38 min
May 5, 3:53 PM EDTSpecial Weather StatementGSPTransylvania37 min
May 5, 4:01 PM EDTSpecial Weather StatementGSPJackson, Transylvania29 min
May 5, 4:24 PM EDTSevere Thunderstorm WarningGSPHenderson, Polk, Transylvania51 min
May 5, 4:30 PM EDTSevere Thunderstorm WarningGSPTransylvania15 min
May 5, 4:49 PM EDTSpecial Weather StatementGSPBuncombe26 min
May 5, 4:52 PM EDTSevere Thunderstorm WarningGSPCleveland, Polk, Rutherford53 min
May 4, 8:06 PM EDTTornado WarningGSPSpartanburg24 min
May 4, 8:24 PM EDTSevere Thunderstorm WarningGSPLaurens, Spartanburg, Union51 min
May 4, 9:14 PM EDTSevere Thunderstorm WarningGSPChester, Union16 min
May 4, 9:19 PM EDTSpecial Weather StatementGSPSpartanburg26 min
May 4, 9:32 PM EDTSpecial Weather StatementGSPChester28 min
May 4, 9:35 PM EDTSpecial Weather StatementGSPUnion25 min
May 4, 9:57 PM EDTSpecial Weather StatementGSPUnion33 min
May 4, 10:56 PM EDTSpecial Weather StatementGSPChester34 min
May 4, 11:28 PM EDTSpecial Weather StatementGSPChester32 min
May 5, 1:24 AM EDTSevere Thunderstorm WarningGSPAnderson, Oconee, Pickens51 min
May 5, 2:00 AM EDTSevere Thunderstorm WarningGSPAbbeville, Anderson, Greenville, Laurens, Oconee, Pickens45 min
May 5, 2:40 AM EDTSevere Thunderstorm WarningGSPAbbeville, Anderson, Cherokee, Greenville, Greenwood, Laurens and 3 more50 min
May 5, 3:18 AM EDTSpecial Weather StatementGSPAnderson27 min
May 5, 4:03 AM EDTSpecial Weather StatementGSPLaurens27 min
May 5, 4:05 PM EDTSpecial Weather StatementGSPPickens25 min
May 5, 4:38 PM EDTSpecial Weather StatementGSPGreenville, Pickens37 min
May 5, 5:04 PM EDTSevere Thunderstorm WarningGSPGreenville, Pickens, Spartanburg41 min
May 5, 5:39 PM EDTSevere Thunderstorm WarningGSPCherokee, Greenville, Spartanburg, Union51 min
May 5, 5:44 PM EDTSpecial Weather StatementGSPGreenville31 min
May 5, 6:09 PM EDTSpecial Weather StatementGSPGreenville, Pickens36 min
May 5, 6:11 PM EDTSevere Thunderstorm WarningGSPChester, Union, York49 min
May 5, 6:32 PM EDTSevere Thunderstorm WarningGSPGreenville, Spartanburg43 min
May 5, 6:35 PM EDTTornado WarningGSPChester25 min
May 5, 6:38 PM EDTTornado WarningGSPChester37 min
May 5, 6:43 PM EDTSevere Thunderstorm WarningGSPOconee47 min
May 5, 6:55 PM EDTSevere Thunderstorm WarningGSPCherokee, Spartanburg, Union50 min
May 5, 7:06 PM EDTSpecial Weather StatementGSPGreenville24 min
May 5, 7:15 PM EDTSpecial Weather StatementGSPUnion30 min
May 5, 7:24 PM EDTSevere Thunderstorm WarningGSPOconee51 min
May 5, 7:28 PM EDTSpecial Weather StatementGSPAnderson32 min
May 5, 7:38 PM EDTSpecial Weather StatementGSPYork37 min
May 5, 7:41 PM EDTSpecial Weather StatementGSPUnion34 min
May 5, 7:42 PM EDTSevere Thunderstorm WarningGSPChester, York37 min
May 5, 7:50 PM EDTSevere Thunderstorm WarningGSPCherokee, Chester, Laurens, Spartanburg, Union, York40 min
May 5, 1:03 AM EDTSpecial Weather StatementGSPHabersham, Rabun27 min
May 5, 3:31 PM EDTSpecial Weather StatementGSPRabun29 min

Nearby

Severe Thunderstorm Warnings in South Carolina, 2020Every severe thunderstorm warning in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.