Alert archive / South Carolina / Mesoscale Discussions in 2012

Mesoscale Discussion 815

May 15, 201210 counties in Georgia; 12 counties in North Carolina; 40 counties in South Carolina

The Storm Prediction Center issued this mesoscale discussion at May 15, 2012, 1:07 PM EDT for 10 counties in Georgia; 12 counties in North Carolina; 40 counties in South Carolina. It was in force for 113 min.

The area

The outline as issued.

The facts

Issued
May 15, 2012, 1:07 PM EDT (17:07 UTC)
Expired
May 15, 2012, 3:00 PM EDT
In force
113 min
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 62 counties

Burke County, GA, Columbia County, GA, Elbert County, GA, Glascock County, GA, Hart County, GA, Lincoln County, GA, McDuffie County, GA, Richmond County, GA, Warren County, GA, Wilkes County, GA, Anson County, NC, Bladen County, NC, Brunswick County, NC, Columbus County, NC, Cumberland County, NC, Hoke County, NC, Mecklenburg County, NC, Richmond County, NC, Robeson County, NC, Sampson County, NC, Scotland County, NC, Union County, NC, Abbeville County, SC, Aiken County, SC, Allendale County, SC, Anderson County, SC, Bamberg County, SC, Barnwell County, SC, Berkeley County, SC, Calhoun County, SC, Cherokee County, SC, Chester County, SC, Chesterfield County, SC, Clarendon County, SC, Darlington County, SC, Dillon County, SC, Dorchester County, SC, Edgefield County, SC, Fairfield County, SC, Florence County, SC, Georgetown County, SC, Greenville County, SC, Greenwood County, SC, Horry County, SC, Kershaw County, SC, Lancaster County, SC, Laurens County, SC, Lee County, SC, Lexington County, SC, Marion County, SC, Marlboro County, SC, McCormick County, SC, Newberry County, SC, Orangeburg County, SC, Pickens County, SC, Richland County, SC, Saluda County, SC, Spartanburg County, SC, Sumter County, SC, Union County, SC, Williamsburg County, SC, York County, SC

The radar

The Columbia radar (KCAE), 64 km from the middle of the area, began a volume at 17:10 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Charleston AFB, SC (KCHS), launched 12:00Z, 5.1 hours before the alert went out and 145 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 2012-05-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1682 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 2012-05-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 51 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
1682 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
555 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
51 m²/s²
0-3 km storm-relative helicity
74 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.5

Open this sounding in Storm Lab

The text

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

411 
ACUS11 KWNS 151707
SWOMCD
SPC MCD 151707 
NCZ000-SCZ000-GAZ000-151900-

MESOSCALE DISCUSSION 0815
NWS STORM PREDICTION CENTER NORMAN OK
1207 PM CDT TUE MAY 15 2012

AREAS AFFECTED...MUCH OF SC...SRN NC...NERN GA

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 151707Z - 151900Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...STORMS WILL INCREASE IN COVERAGE AND INTENSITY OVER THE
NEXT FEW HOURS. SEVERE HAIL AND WIND ARE LIKELY.

DISCUSSION...VISIBLE IMAGERY SHOWS AREAS OF TOWERING CU OVER W CNTRL
SC NEAR A WEAK LOW PRESSURE TROUGH...AS WELL AS OVER ERN SC/SERN NC
NEAR THE SEA BREEZE. WITH STRONG HEATING AND AMPLE
MOISTURE...VIGOROUS UPDRAFTS WILL DEVELOP. WIND PROFILES ARE WEAK IN
THE LOW TO MID LEVELS...BUT WILL INCREASE IN THE MID TO UPPER LEVELS
AS A WEAK SHORTWAVE TROUGH AFFECTS THE AREA. TALL STORMS CAPABLE OF
1.00 - 1.75 INCH DIAMETER HAIL ARE LIKELY...AND SOME STRONG TO
SEVERE WINDS MAY OCCUR WITH DOWNBURSTS...ALTHOUGH AN ORGANIZED WIND
THREAT IS NOT EXPECTED ON THE LARGE SCALE.

..JEWELL/HART.. 05/15/2012

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...RAH...ILM...CHS...CAE...GSP...FFC...

LAT...LON   33067939 32788141 33158257 33698297 34508314 35158249
            35248179 35298059 35297939 35077842 34277787 33877824
            33617879 33067939

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 15, 2:27 PM EDTSevere Thunderstorm WatchSPCBryan, Bulloch, Burke, Candler, Chatham, Columbia and 11 more7 hr
May 15, 3:13 PM EDTSevere Thunderstorm WatchSPCElbert, Franklin, Habersham, Hart, Rabun, Stephens7 hr
May 15, 5:38 PM EDTMesoscale DiscussionSPCBrantley, Camden, Charlton97 min
May 15, 6:30 PM EDTMesoscale DiscussionSPCBryan, Bulloch, Burke, Candler, Chatham, Columbia and 16 more90 min
May 15, 2:08 PM EDTMesoscale DiscussionSPCAlamance, Alexander, Alleghany, Burke, Caldwell, Caswell and 21 more67 min

Nearby

Mesoscale Discussions in South Carolina, 2012Mesoscale Discussions in North Carolina, 2012Mesoscale Discussions in Georgia, 2012Every mesoscale discussion in 2012

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.