Alert archive / South Carolina / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 21, NWS Columbia, SC

April 24, 1999Bamberg County, South Carolina

NWS Columbia, SC issued this severe thunderstorm warning at Apr 24, 1999, 6:33 PM EDT for Bamberg County, South Carolina. It was in force for 42 min. 1 report 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: Apr 24, 1999, 6:33 PM EDT (22:33 UTC)
Expired: Apr 24, 1999, 7:15 PM EDT
In force: 42 min
Issued by: NWS Columbia, SC
Area: Whole counties

County Bamberg County, SC

The radar

The Charleston,SC radar (KCLX), 62 km from the middle of the area, began a volume at 22:33 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

Time	Report	Where	Remark
Apr 24, 6:35 PM EDT	Hail 1.75	Olar, SC	Police reported golf ball size hail covering ground.

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.

Issued	Product	Office	Lasted
Apr 24, 4:30 PM EDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Charleston AFB, SC (KCHS), launched 12:00Z, 10.6 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-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: 1256 J/kg
Mixed-layer CIN: -147 J/kg
Mixed-layer LCL: 1157 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 105 m²/s²
0-3 km storm-relative helicity: 125 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KCAE 242233 RRA
SVRCAE
SCC009-242315-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE COLUMBIA SC
633 PM EDT SAT APR 24 1999

THE NATIONAL WEATHER SERVICE IN COLUMBIA SC HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN BAMBERG COUNTY IN SOUTH CAROLINA

* UNTIL 715 PM EDT 

* AT 632 PM EDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
  A SEVERE THUNDERSTORM 10 MILES WEST-NORTHWEST OF OLAR. THE 
  STORM WAS MOVING TOWARD THE SOUTHEAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  OLAR AT 657 PM EDT

SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES 
WITH LITTLE OR NO ADVANCE WARNING. REMAIN CALM BUT BE ALERT TO 
RAPIDLY CHANGING WEATHER CONDITIONS.

THIS IS A DANGEROUS STORM...TAKE COVER IMMEDIATELY IF YOU ARE IN 
ITS PATH. INTENSE SEVERE THUNDERSTORMS CAN CAUSE AS MUCH DAMAGE 
AS SOME TORNADOES.

AMATEUR RADIO AND OTHER SPOTTERS ARE REQUESTED TO MONITOR THIS 
STORM AND RELAY REPORTS PROMPTLY TO THE NEAREST NATIONAL WEATHER 
SERVICE OFFICE.

JDB

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 24, 3:59 PM EDT	Severe Thunderstorm Warning	CAE	Bamberg	31 min
Apr 24, 4:25 PM EDT	Tornado Warning	CAE	Newberry	65 min
Apr 24, 4:39 PM EDT	Tornado Warning	CAE	Saluda	66 min
Apr 24, 5:20 PM EDT	Tornado Warning	CAE	Aiken	25 min
Apr 24, 5:39 PM EDT	Tornado Warning	CAE	Aiken	51 min
Apr 24, 6:03 PM EDT	Severe Thunderstorm Warning	CAE	Barnwell	42 min

Nearby

Severe Thunderstorm Warnings in South Carolina, 1999 Every 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.