Alert archive / North Carolina / Mesoscale Discussions in 2012

Mesoscale Discussion 1377

July 3, 20125 states

The Storm Prediction Center issued this mesoscale discussion at Jul 3, 2012, 6:23 PM EDT for 5 states. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Jul 3, 2012, 6:23 PM EDT (22:23 UTC)
Expired: Jul 3, 2012, 9:00 PM EDT
In force: 3 hr
Issued by: the Storm Prediction Center
Chance of a watch: 5%

All 150 counties

Franklin County, GA, Habersham County, GA, Hart County, GA, Rabun County, GA, Stephens County, GA, Towns County, GA, Union County, GA, White County, GA, Alamance County, NC, Alexander County, NC, Alleghany County, NC, Anson County, NC, Ashe County, NC, Avery County, NC, Buncombe County, NC, Burke County, NC, Cabarrus County, NC, Caldwell County, NC, Caswell County, NC, Catawba County, NC, Chatham County, NC, Cherokee County, NC, Clay County, NC, Cleveland County, NC, Cumberland County, NC, Davidson County, NC, Davie County, NC, Durham County, NC, Forsyth County, NC, Franklin County, NC, Gaston County, NC, Graham County, NC, Granville County, NC, Guilford County, NC, Harnett County, NC, Haywood County, NC, Henderson County, NC, Hoke County, NC, Iredell County, NC, Jackson County, NC, Johnston County, NC, Lee County, NC, Lincoln County, NC, Macon County, NC, Madison County, NC, McDowell County, NC, Mecklenburg County, NC, Mitchell County, NC, Montgomery County, NC, Moore County, NC, Nash County, NC, Orange County, NC, Person County, NC, Polk County, NC, Randolph County, NC, Richmond County, NC, Rockingham County, NC, Rowan County, NC, Rutherford County, NC, Scotland County, NC, Stanly County, NC, Stokes County, NC, Surry County, NC, Swain County, NC, Transylvania County, NC, Union County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Watauga County, NC, Wilkes County, NC, Yadkin County, NC, Yancey County, NC, Abbeville County, SC, Anderson County, SC, Cherokee County, SC, Chester County, SC, Chesterfield County, SC, Fairfield County, SC, Greenville County, SC, Greenwood County, SC, Kershaw County, SC, Lancaster County, SC, Laurens County, SC, Marlboro County, SC, Newberry County, SC, Oconee County, SC, Pickens County, SC, Spartanburg County, SC, Union County, SC, York County, SC, Blount County, TN, Carter County, TN, Cocke County, TN, Greene County, TN, Jefferson County, TN, Johnson County, TN, Sevier County, TN, Sullivan County, TN, Unicoi County, TN, Washington County, TN, Amelia County, VA, Appomattox County, VA, Bedford County, VA, Bland County, VA, Brunswick County, VA, Buckingham County, VA, Campbell County, VA, Carroll County, VA, Charlotte County, VA, Chesterfield County, VA, City of Bristol, VA, City of Colonial Heights, VA, City of Danville, VA, City of Emporia, VA, City of Galax, VA, City of Hopewell, VA, City of Lynchburg, VA, City of Martinsville, VA, City of Petersburg, VA, City of Radford, VA, City of Richmond, VA, City of Roanoke, VA, City of Salem, VA, Cumberland County, VA, Dinwiddie County, VA, Floyd County, VA, Franklin County, VA, Giles County, VA, Goochland County, VA, Grayson County, VA, Greensville County, VA, Halifax County, VA, Hanover County, VA, Henrico County, VA, Henry County, VA, Lunenburg County, VA, Mecklenburg County, VA, Montgomery County, VA, Nottoway County, VA, Patrick County, VA, Pittsylvania County, VA, Powhatan County, VA, Prince Edward County, VA, Pulaski County, VA, Roanoke County, VA, Smyth County, VA, Tazewell County, VA, Washington County, VA, Wythe County, VA

The radar

The Roanoke radar (KFCX), 92 km from the middle of the area, began a volume at 22:26 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 nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 10.4 hours before the alert went out and 57 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: 642 J/kg
Mixed-layer CIN: -127 J/kg
Mixed-layer LCL: 1732 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: -21 m²/s²
0-3 km storm-relative helicity: -7 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

064 
ACUS11 KWNS 032224
SWOMCD
SPC MCD 032223
VAZ000-NCZ000-SCZ000-WVZ000-TNZ000-GAZ000-040100-

MESOSCALE DISCUSSION 1377
NWS STORM PREDICTION CENTER NORMAN OK
0523 PM CDT TUE JUL 03 2012

AREAS AFFECTED...SRN VA...CNTRL/WRN NC...NRN SC...ERN TN...FAR NERN
GA...FAR SRN WV

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 032223Z - 040100Z

PROBABILITY OF WATCH ISSUANCE...5 PERCENT

SUMMARY...A VERY ISOLATED MARGINALLY SVR THUNDERSTORM THREAT WILL
EXIST ACROSS PARTS OF THE CNTRL/SRN APPALACHIANS AND ADJACENT
PIEDMONT REGION INTO EARLY EVENING. A WW IS NOT NEEDED.

DISCUSSION...OROGRAPHIC ASCENT ASSOCIATED WITH TERRAIN-INDUCED
CIRCULATIONS HAS FOSTERED THE DEVELOPMENT OF SCATTERED THUNDERSTORMS
FROM SWRN VA TO NERN GA. WLY TO NLY FLOW OF 10-20 KT IN THE LOW/MID
LEVELS PER GREENVILLE-SPARTANBURG/MORRISTOWN/ROANOKE VWP DATA WILL
AID IN ISOLATED CONVECTION MOVING ONTO THE PIEDMONT REGION DURING
THE NEXT FEW HOURS WHERE A NE-SW-ORIENTED LEE TROUGH EXISTS. ALONG
THE TROUGH AXIS...WEAK LOW-LEVEL ASCENT BENEATH APPROACHING ANVIL
SHADING /SUBTLE DIABATIC COOLING/ WILL LARGELY LIMIT INITIATION
ALONG THE TROUGH AXIS...THOUGH ANY STORMS INTERACTING WITH THE AXIS
MAY BE LOCALLY ENHANCED. MODERATE INSTABILITY -- MLCAPE VALUES OF
1000-2000 J/KG -- MAY PROMOTE OCCASIONAL VIGOROUS UPDRAFTS WITH A
VERY ISOLATED MARGINALLY SVR HAIL THREAT. DCAPE VALUES IN EXCESS OF
900 J/KG WILL ALSO PROVIDE A THREAT FOR VERY ISOLATED MARGINALLY SVR
WIND GUSTS WITH MICROBURSTS. WEAK DEEP SHEAR IN PLACE WILL KEEP
CONVECTION LARGELY DISORGANIZED...WITH ANY SVR THREAT
BRIEF/SPORADIC. AND...WITH THE EVENTUAL ONSET OF DIABATIC
COOLING/STABILIZATION...STORMS SHOULD WEAKEN IN COVERAGE AND
INTENSITY AFTER 00Z.

..COHEN/HART.. 07/03/2012

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

ATTN...WFO...AKQ...RAH...ILM...RNK...RLX...CAE...GSP...MRX...
FFC...

LAT...LON   38017778 37867735 37307723 36727743 35857796 34707915
            34298045 34038178 34048260 34338333 34818424 35308439
            35978368 36468272 36918198 37358129 37468066 37447964
            37547871 38017778

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 3, 6:59 PM EDT	Mesoscale Discussion	SPC	Appling, Atkinson, Bacon, Baker, Bartow, Ben Hill and 106 more	3 hr
Jul 3, 5:58 PM EDT	Mesoscale Discussion	SPC	Albemarle, Alleghany, Amherst, Augusta, Bath, Botetourt and 24 more	3 hr

Nearby

Mesoscale Discussions in North Carolina, 2012 Mesoscale Discussions in Virginia, 2012 Mesoscale Discussions in South Carolina, 2012 Every 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.