Alert archive / South Carolina / Mesoscale Discussions in 2011

Mesoscale Discussion 385

April 9, 201110 counties in Georgia; 23 counties in South Carolina

The Storm Prediction Center issued this mesoscale discussion at Apr 9, 2011, 1:34 PM EDT for 10 counties in Georgia; 23 counties in South Carolina. It was in force for 86 min.

The area

The outline as issued.

The facts

Issued: Apr 9, 2011, 1:34 PM EDT (17:34 UTC)
Expired: Apr 9, 2011, 3:00 PM EDT
In force: 86 min
Issued by: the Storm Prediction Center

All 33 counties

Columbia County, GA, Elbert County, GA, Franklin County, GA, Habersham County, GA, Hart County, GA, Lincoln County, GA, Rabun County, GA, Richmond County, GA, Stephens County, GA, White County, GA, Abbeville County, SC, Aiken County, SC, Allendale County, SC, Anderson County, SC, Bamberg County, SC, Barnwell County, SC, Calhoun County, SC, Dorchester County, SC, Edgefield County, SC, Fairfield County, SC, Greenville County, SC, Greenwood County, SC, Laurens County, SC, Lexington County, SC, McCormick County, SC, Newberry County, SC, Oconee County, SC, Orangeburg County, SC, Pickens County, SC, Richland County, SC, Saluda County, SC, Spartanburg County, SC, Union County, SC

The radar

The Greer radar (KGSP), 70 km from the middle of the area, began a volume at 17:34 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.

Severe Thunderstorm Watch 114Apr 9, 2:45 PM EDT

The nearest sounding before it

Charleston AFB, SC (KCHS), launched 12:00Z, 5.6 hours before the alert went out and 238 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: 2220 J/kg
Mixed-layer CIN: -65 J/kg
Mixed-layer LCL: 712 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: -4 m²/s²
0-3 km storm-relative helicity: 30 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.3

Open this sounding in Storm Lab

The text

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

048 
ACUS11 KWNS 091734
SWOMCD
SPC MCD 091734 
SCZ000-GAZ000-NCZ000-091900-

MESOSCALE DISCUSSION 0385
NWS STORM PREDICTION CENTER NORMAN OK
1234 PM CDT SAT APR 09 2011

AREAS AFFECTED...NERN GA THROUGH SC

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 091734Z - 091900Z

STORMS ARE EXPECTED TO DEVELOP FROM NERN GA INTO SC THIS AFTERNOON.
SUPERCELLS AND BOWING SEGMENTS WITH ISOLATED LARGE HAIL AND DAMAGING
WIND WILL BE THE MAIN THREATS. WW WILL LIKELY BE NEEDED SOON.

STRONG DIABATIC WARMING HAS BOOSTED TEMPERATURES INTO THE 80S FROM
NERN GA INTO SC WHICH IN CONJUNCTION WITH MID-UPPER 60S DEWPOINTS
AND 7-7.5 MID LEVEL LAPSE RATES ARE CONTRIBUTING TO 2000-2500 J/KG
MLCAPE. OBJECTIVE ANALYSIS INDICATE CINH IS WEAKENING...AND
THUNDERSTORM INITIATION MAY BECOME IMMINENT BY 18-19Z. POTENTIAL
WILL EXIST FOR STORMS TO DEVELOP ALONG BACKDOOR FRONT MOVING WWD
THROUGH NERN SC AS WELL AS OVER THE HIGHER TERRAIN FROM NERN GA INTO
SWRN NC AND WRN SC...AND SUBSEQUENTLY MOVE SEWD. VERTICAL SHEAR TO
50 KT WILL SUPPORT SUPERCELLS AND BOWING SEGMENTS.

..DIAL.. 04/09/2011

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

ATTN...WFO...CHS...CAE...GSP...FFC...

LAT...LON   35268258 34598102 33108021 32818135 34748398 35268258

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 9, 2:44 PM EDT	Severe Thunderstorm Watch	SPC	Bryan, Bulloch, Burke, Candler, Chatham, Columbia and 11 more	6 hr
Apr 9, 5:36 PM EDT	Mesoscale Discussion	SPC	Abbeville, Aiken, Bamberg, Barnwell, Berkeley, Calhoun and 29 more	54 min
Apr 9, 6:16 PM EDT	Tornado Watch	SPC	Abbeville, Aiken, Anderson, Bamberg, Barnwell, Calhoun and 25 more	6 hr
Apr 9, 7:59 PM EDT	Mesoscale Discussion	SPC	Calhoun, Cherokee, Chester, Chesterfield, Clarendon, Darlington and 17 more	61 min

Nearby

Mesoscale Discussions in South Carolina, 2011 Mesoscale Discussions in Georgia, 2011 Every mesoscale discussion in 2011

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.