Alert archive / South Carolina / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 221, NWS Greenville-Spartanburg, SC

July 20, 2020Union County, South Carolina

NWS Greenville-Spartanburg, SC issued this severe thunderstorm warning at Jul 20, 2020, 5:19 PM EDT for Union County, South Carolina. It was in force for 22 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: Jul 20, 2020, 5:19 PM EDT (21:19 UTC)
Expired: Jul 20, 2020, 5:41 PM EDT
In force: 22 min
Issued by: NWS Greenville-Spartanburg, SC
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Union County, SC

The radar

The Greer radar (KGSP), 59 km from the middle of the area, began a volume at 21:20 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

Charleston AFB, SC (KCHS), launched 12:00Z, 9.3 hours before the alert went out and 249 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 601 J/kg
Mixed-layer CIN: -87 J/kg
Mixed-layer LCL: 1172 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 13 m²/s²
0-3 km storm-relative helicity: 33 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 Jul 20, 2:41 PM EDT, 2 hours 38 minutes earlier.

Area forecast discussion, Jul 20, 2:41 PM EDT, 2 hours 38 minutes before

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Hazardous weather outlook, Jul 20, 2:58 PM EDT, 2 hours 21 minutes before

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In the hours before

Special weather statement, Jul 20, 4:23 PM EDT, 56 minutes before

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Special weather statement, Jul 20, 4:29 PM EDT, 50 minutes before

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Special weather statement, Jul 20, 4:31 PM EDT, 48 minutes before

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Special weather statement, Jul 20, 4:35 PM EDT, 44 minutes before

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Special weather statement, Jul 20, 4:45 PM EDT, 34 minutes before

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Special weather statement, Jul 20, 4:51 PM EDT, 28 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 20, 1:59 PM EDT	Severe Thunderstorm Warning	GSP	Avery, Burke, Caldwell	46 min
Jul 20, 2:24 PM EDT	Special Weather Statement	GSP	Transylvania	36 min
Jul 20, 2:36 PM EDT	Special Weather Statement	GSP	Buncombe	24 min
Jul 20, 2:45 PM EDT	Special Weather Statement	GSP	Caldwell	30 min
Jul 20, 2:49 PM EDT	Heat Advisory	GSP	Cabarrus, Davie, Iredell, Mecklenburg, Rowan, Union	29 hr
Jul 20, 3:00 PM EDT	Special Weather Statement	GSP	Buncombe	30 min
Jul 20, 3:09 PM EDT	Special Weather Statement	GSP	Alexander	36 min
Jul 20, 3:25 PM EDT	Special Weather Statement	GSP	Polk	35 min
Jul 20, 3:29 PM EDT	Severe Thunderstorm Warning	GSP	Buncombe, Henderson, McDowell, Polk, Rutherford	46 min
Jul 20, 3:42 PM EDT	Special Weather Statement	GSP	Burke	33 min
Jul 20, 3:45 PM EDT	Special Weather Statement	GSP	Alexander	30 min
Jul 20, 4:02 PM EDT	Severe Thunderstorm Warning	GSP	Alexander, Davie, Iredell	43 min
Jul 20, 4:06 PM EDT	Special Weather Statement	GSP	Union	24 min
Jul 20, 4:09 PM EDT	Special Weather Statement	GSP	Cleveland	36 min
Jul 20, 4:15 PM EDT	Severe Thunderstorm Warning	GSP	Cleveland	32 min
Jul 20, 4:19 PM EDT	Severe Thunderstorm Warning	GSP	Rutherford	41 min
Jul 20, 4:31 PM EDT	Special Weather Statement	GSP	Catawba	29 min
Jul 20, 4:45 PM EDT	Special Weather Statement	GSP	Union	30 min
Jul 20, 4:49 PM EDT	Severe Thunderstorm Warning	GSP	Union	41 min
Jul 20, 5:05 PM EDT	Severe Thunderstorm Warning	GSP	Gaston, Mecklenburg	40 min
Jul 20, 5:25 PM EDT	Severe Thunderstorm Warning	GSP	Cleveland, Rutherford	35 min
Jul 20, 5:28 PM EDT	Severe Thunderstorm Warning	GSP	Mecklenburg	27 min
Jul 20, 5:34 PM EDT	Severe Thunderstorm Warning	GSP	Cleveland	26 min
Jul 20, 5:39 PM EDT	Special Weather Statement	GSP	Polk	36 min
Jul 20, 6:00 PM EDT	Severe Thunderstorm Warning	GSP	Cleveland	45 min
Jul 20, 6:20 PM EDT	Special Weather Statement	GSP	Cabarrus, Mecklenburg	25 min
Jul 20, 6:28 PM EDT	Severe Thunderstorm Warning	GSP	Cabarrus, Mecklenburg, Rowan	35 min
Jul 20, 7:05 PM EDT	Special Weather Statement	GSP	Lincoln	25 min
Jul 20, 3:04 PM EDT	Special Weather Statement	GSP	Chester	26 min
Jul 20, 3:33 PM EDT	Special Weather Statement	GSP	Chester	27 min
Jul 20, 4:05 PM EDT	Special Weather Statement	GSP	Chester	25 min
Jul 20, 4:23 PM EDT	Special Weather Statement	GSP	York	37 min
Jul 20, 4:29 PM EDT	Special Weather Statement	GSP	Chester	31 min
Jul 20, 4:35 PM EDT	Special Weather Statement	GSP	Spartanburg	25 min
Jul 20, 4:41 PM EDT	Severe Thunderstorm Warning	GSP	Spartanburg	49 min
Jul 20, 4:51 PM EDT	Special Weather Statement	GSP	Union	24 min
Jul 20, 5:10 PM EDT	Severe Thunderstorm Warning	GSP	Cherokee, Chester, Union, York	20 min
Jul 20, 5:17 PM EDT	Severe Thunderstorm Warning	GSP	Laurens	43 min
Jul 20, 6:36 PM EDT	Special Weather Statement	GSP	Abbeville	24 min
Jul 20, 6:51 PM EDT	Severe Thunderstorm Warning	GSP	Abbeville, Greenwood, Laurens	24 min
Jul 20, 7:15 PM EDT	Severe Thunderstorm Warning	GSP	Abbeville, Greenwood, Laurens	30 min

Nearby

Severe Thunderstorm Warnings in South Carolina, 2020 Every 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.