Alert archive / South Carolina / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 105, NWS Columbia, SC

August 24, 2002Lexington County, Richland County, South Carolina

NWS Columbia, SC issued this severe thunderstorm warning at Aug 24, 2002, 7:45 PM EDT for Lexington County, Richland County, South Carolina. It was in force for 30 min. 3 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: Aug 24, 2002, 7:45 PM EDT (23:45 UTC)
Expired: Aug 24, 2002, 8:15 PM EDT
In force: 30 min
Issued by: NWS Columbia, SC
Area: Counties, with a storm outline in the text

Counties Lexington County, SC, Richland County, SC

The radar

The Columbia radar (KCAE), 3 km from the middle of the area, began a volume at 23:45 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
Aug 24, 7:50 PM EDT	Thunderstorm Wind 55 E	Cayce, SC	Sheriff reported trees and powerlines down in Cayce and Pinegrove.
Aug 24, 7:55 PM EDT	Thunderstorm Wind 55 E	Columbia, SC	Sheriff reported trees and powerlines down in South Columbia and portions of Lower Richland county.
Aug 24, 8:10 PM EDT	Thunderstorm Wind 50 E	Chapin, SC	Fire Dept reported a couple of trees down on Amicks Ferry Road.

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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Charleston AFB, SC (KCHS), launched 12:00Z, 11.8 hours before the alert went out and 155 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: 2172 J/kg
Mixed-layer CIN: -89 J/kg
Mixed-layer LCL: 831 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 19 m²/s²
0-3 km storm-relative helicity: 8 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 Columbia, SC wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 24, 2:25 PM EDT, 5 hours 20 minutes earlier.

Area forecast discussion, Aug 24, 2:25 PM EDT, 5 hours 20 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
225 PM EDT SAT AUG 24 2002

MODELS NOW MORE IN LINE WITH EACH OTHER IN THE NEAR TERM WEATHER
SITUATION. ETA/AVN/MRF ALL SEEM TO BE IN GENERAL AGREEMENT ON
DEVELOPMENT OF CUT OFF UPPER LOW OVER OH VALLEY BY LATE SUNDAY OR
EARLY MONDAY. IN THE MEANTIME...EXPECT ONE MORE DAY OF DAYTIME MAXES
REACHING THE MID TO UPPER 90S FOR SUNDAY. COLD FRONT CURRENTLY
EXTENDING ACROSS OH VALLEY WILL SLOWLY PUSH TO THE SOUTHEAST. WITH
WEAK SURFACE THERMAL TROUGH REMAINING ACROSS THE CWA THIS
EVENING...WILL KEEP MENTION OF ISOLATED POPS FOR THE EARLY EVENING.
AS COLD FRONT DRAWS CLOSER TO THE STATE SUNDAY...WILL INCREASE POPS
TO AROUND 30 PERCENT FOR THE AFTERNOON. MODELS SEEM TO INDICATE THAT
BEST OPPORTUNITY FOR PRECIPITATION WILL BE LATE SUNDAY INTO MONDAY
AS FRONT IS EXPECTED TO STALL ACROSS THE CAROLINAS AND THE OH VALLEY
UPPER LOW INDUCES CYCLOGENESIS OVER SC OR GA BY MONDAY. WITH CURRENT
DROUGHT SITUATION...GENERALLY LEANED ON LOW SIDE OF POP
GUIDANCE...BUT HIGH CHANCE POPS LOOK GOOD FOR MONDAY.

FOR THE EXTENDED...AVN AND MRF IN GENERAL SLOWLY RETROGRADE UPPER
LOW AND WEAKEN IT BY WEDNESDAY OR THURSDAY. WITH FRONT IN THE
VICINITY...WILL KEEP CHANCE OF PRECIPITATION IN FORECAST UNTIL
THURSDAY. BERMUDA HIGH REBUILDS INTO AREA FRIDAY AND SATURDAY AND
FOR NOW WILL NOT MENTION RAIN CHANCES FOR LATE IN THE EXTENDED.

OVERALL CONSENSUS OF MODEL GUIDANCE AND LOCAL EQUATIONS LOOKS
REASONABLE FOR TEMPS AND POPS.

FCSTID = 22
CAE   75  97  73  87 /  10  30  40  50
AGS   74  97  72  87 /  10  30  40  50
SSC   74  97  73  86 /  10  30  40  50
OGB   75  97  73  87 /  10  30  40  50

.CAE...
GA...NONE.
SC...NONE.

BC

Nearby

Severe Thunderstorm Warnings in South Carolina, 2002 Every severe thunderstorm warning in 2002

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.