Alert archive / South Carolina / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 46, NWS Columbia, SC

May 6, 1999Calhoun County, Orangeburg County, South Carolina

NWS Columbia, SC issued this severe thunderstorm warning at May 6, 1999, 3:24 PM EDT for Calhoun County, Orangeburg County, South Carolina. It was in force for 51 min. 2 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
May 6, 1999, 3:24 PM EDT (19:24 UTC)
Expired
May 6, 1999, 4:15 PM EDT
In force
51 min
Issued by
NWS Columbia, SC
Area
Whole counties

Counties Calhoun County, SC, Orangeburg County, SC

The radar

The Columbia radar (KCAE), 53 km from the middle of the area, began a volume at 19:23 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.

What was reported inside it

TimeReportWhereRemark
May 6, 3:40 PM EDTThunderstorm Wind 50St Matthews, SCSheriff reported trees down at Sandy Run.
May 6, 3:45 PM EDTThunderstorm Wind 50North, SCEOC reported trees down in North and Neeses.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 6, 3:00 PM EDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Charleston AFB, SC (KCHS), launched 12:00Z, 7.4 hours before the alert went out and 104 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, Charleston AFB, SC at 12:00Z on 1999-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 479 joules per kilogram.LCLLFCEL10008507005003002001001 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, Charleston AFB, SC at 12:00Z on 1999-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 120 square meters per square second.193958Sfc1 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
479 J/kg
Mixed-layer CIN
-203 J/kg
Mixed-layer LCL
961 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
120 m²/s²
0-3 km storm-relative helicity
199 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.4

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KCAE 061924 RRA
SVRCAE
SCC017-075-062015-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE COLUMBIA SC
324 PM EDT THU MAY 6 1999

THE NATIONAL WEATHER SERVICE IN COLUMBIA SC HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CALHOUN COUNTY IN SOUTH CAROLINA
  ORANGEBURG COUNTY IN SOUTH CAROLINA

* UNTIL 415 PM EDT 

* AT 322 PM...RADAR INDICATED A LINE OF SEVERE THUNDERSTORMS 
  THAT STRETCHED FROM NEAR COLUMBIA SOUTHWEST TO SWANSEA AND 
  SOUTHWEST TO NEAR SPRINGFIELD. THE LINE WAS MOVING TO THE 
  EAST AROUND 45 MPH. THIS LINE HAD A HISTORY OF PRODUCING SEVERE 
  WEATHER WITH WIND GUSTS OVER 55 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  SANDY RUN  AT 327 PM
  LIVINGSTON AT 335 PM
  ORANGEBURG AT 345 PM

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55 MPH... 
DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR YOUR 
PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR.

The office that day

Everything else NWS Columbia, SC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 6, 2:00 PM EDTSevere Thunderstorm WarningCAEEdgefield, McCormick30 min
May 6, 2:06 PM EDTSevere Thunderstorm WarningCAEEdgefield, McCormick39 min
May 6, 2:10 PM EDTSevere Thunderstorm WarningCAERichland35 min
May 6, 2:15 PM EDTSevere Thunderstorm WarningCAESaluda45 min
May 6, 2:19 PM EDTSevere Thunderstorm WarningCAELancaster41 min
May 6, 2:24 PM EDTSevere Thunderstorm WarningCAELee51 min
May 6, 2:37 PM EDTSevere Thunderstorm WarningCAEKershaw53 min
May 6, 2:44 PM EDTSevere Thunderstorm WarningCAEAiken46 min
May 6, 2:57 PM EDTSevere Thunderstorm WarningCAELexington, Newberry48 min
May 6, 3:03 PM EDTSevere Thunderstorm WarningCAEFairfield42 min
May 6, 3:07 PM EDTSevere Thunderstorm WarningCAERichland68 min
May 6, 3:13 PM EDTSevere Thunderstorm WarningCAELee47 min
May 6, 3:28 PM EDTSevere Thunderstorm WarningCAEChesterfield32 min
May 6, 3:34 PM EDTSevere Thunderstorm WarningCAEKershaw41 min
May 6, 3:42 PM EDTSevere Thunderstorm WarningCAESumter63 min
May 6, 3:57 PM EDTTornado WarningCAESumter48 min
May 6, 4:09 PM EDTSevere Thunderstorm WarningCAELee51 min
May 6, 4:13 PM EDTTornado WarningCAEKershaw, Lee47 min
May 6, 4:26 PM EDTSevere Thunderstorm WarningCAEClarendon49 min
May 6, 4:29 PM EDTSevere Thunderstorm WarningCAEChesterfield46 min

Nearby

Severe Thunderstorm Warnings in South Carolina, 1999Every severe thunderstorm warning in 1999

Sources

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