Alert archive / North Carolina / Mesoscale Discussions in 2012

Mesoscale Discussion 1572

July 24, 201246 counties in North Carolina; 7 counties in South Carolina; 34 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Jul 24, 2012, 3:46 PM EDT for 46 counties in North Carolina; 7 counties in South Carolina; 34 counties in Virginia. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued
Jul 24, 2012, 3:46 PM EDT (19:46 UTC)
Expired
Jul 24, 2012, 5:15 PM EDT
In force
89 min
Issued by
the Storm Prediction Center
Chance of a watch
95%
All 87 counties

Beaufort County, NC, Bertie County, NC, Bladen County, NC, Brunswick County, NC, Camden County, NC, Carteret County, NC, Chowan County, NC, Columbus County, NC, Craven County, NC, Cumberland County, NC, Currituck County, NC, Dare County, NC, Duplin County, NC, Edgecombe County, NC, Franklin County, NC, Gates County, NC, Greene County, NC, Halifax County, NC, Harnett County, NC, Hertford County, NC, Hoke County, NC, Hyde County, NC, Johnston County, NC, Jones County, NC, Lee County, NC, Lenoir County, NC, Martin County, NC, Nash County, NC, New Hanover County, NC, Northampton County, NC, Onslow County, NC, Pamlico County, NC, Pasquotank County, NC, Pender County, NC, Perquimans County, NC, Pitt County, NC, Richmond County, NC, Robeson County, NC, Sampson County, NC, Scotland County, NC, Tyrrell County, NC, Wake County, NC, Warren County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC, Darlington County, SC, Dillon County, SC, Florence County, SC, Horry County, SC, Marion County, SC, Marlboro County, SC, Williamsburg County, SC, Accomack County, VA, Brunswick County, VA, Charles City County, VA, City of Chesapeake, VA, City of Colonial Heights, VA, City of Emporia, VA, City of Franklin, VA, City of Hampton, VA, City of Hopewell, VA, City of Newport News, VA, City of Norfolk, VA, City of Petersburg, VA, City of Poquoson, VA, City of Portsmouth, VA, City of Suffolk, VA, City of Virginia Beach, VA, City of Williamsburg, VA, Dinwiddie County, VA, Gloucester County, VA, Greensville County, VA, Henrico County, VA, Isle of Wight County, VA, James City County, VA, Lancaster County, VA, Mathews County, VA, Middlesex County, VA, New Kent County, VA, Northampton County, VA, Northumberland County, VA, Prince George County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA, York County, VA

The radar

The Morehead City radar (KMHX), 97 km from the middle of the area, began a volume at 19:47 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

Newport, NC (KMHX), launched 12:00Z, 7.8 hours before the alert went out and 96 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, Newport, NC at 12:00Z on 2012-07-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1601 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, Newport, NC at 12:00Z on 2012-07-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 199 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
1601 J/kg
Mixed-layer CIN
-80 J/kg
Mixed-layer LCL
888 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
199 m²/s²
0-3 km storm-relative helicity
232 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.

158 
ACUS11 KWNS 241946
SWOMCD
SPC MCD 241946 
VAZ000-NCZ000-MDZ000-SCZ000-242115-

MESOSCALE DISCUSSION 1572
NWS STORM PREDICTION CENTER NORMAN OK
0246 PM CDT TUE JUL 24 2012

AREAS AFFECTED...SERN VA...ERN NC...FAR NERN SC

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 241946Z - 242115Z

PROBABILITY OF WATCH ISSUANCE...95 PERCENT

SUMMARY...STORMS SHOULD CONTINUE TO INCREASE IN COVERAGE...AND FILL
IN OVER SERN VA...ERN NC AND PERHAPS NERN SC. A NEW WATCH IS LIKELY
FOR DAMAGING WINDS AND HAIL WITHIN THE HOUR.

DISCUSSION...SURFACE ANALYSIS SHOWS A WLY SURGE INCREASING
CONVERGENCE ALONG AN AXIS FROM RIC SWWD INTO CNTRL NC. VIGOROUS
STORMS HAVE BEEN INCREASING IN COVERAGE OVER NC...WITH NEW
DEVELOPMENT NOW INTO SERN VA. STRONG INSTABILITY/HIGH
PWAT...SUFFICIENT SHEAR FOR ORGANIZED/LONG LIVED SEVERE AND STEEP
LOW LEVEL LAPSE RATES WILL ALL CONTRIBUTE TO A DAMAGING WIND AND
HAIL THREAT WITH THESE STORMS UNTIL THEY EXIT THE COAST.

..JEWELL/HART.. 07/24/2012

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

ATTN...WFO...AKQ...MHX...RAH...ILM...CAE...

LAT...LON   33337877 33667987 34137998 34867994 35797896 36817795
            37467735 37907642 37967536 37087572 36237561 35687529
            35127536 34927600 34537644 33337877

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 24, 1:08 PM EDTSevere Thunderstorm WatchSPCAlleghany, Ashe, Caswell, Rockingham, Stokes, Surry and 3 more6 hr
Jul 24, 1:12 PM EDTMesoscale DiscussionSPCAlamance, Alexander, Anson, Avery, Buncombe, Burke and 37 more93 min
Jul 24, 1:42 PM EDTMesoscale DiscussionSPCBertie, Camden, Chowan, Currituck, Gates, Halifax and 8 more2 hr
Jul 24, 2:36 PM EDTSevere Thunderstorm WatchSPCAlamance, Alexander, Anson, Avery, Buncombe, Burke and 53 more5 hr
Jul 24, 4:24 PM EDTSevere Thunderstorm WatchSPCBeaufort, Bertie, Bladen, Brunswick, Camden, Carteret and 24 more4 hr
Jul 24, 6:46 PM EDTMesoscale DiscussionSPCCalhoun, Clarendon, Lee, Lexington, Richland, Saluda and 1 more89 min
Jul 24, 11:43 AM EDTMesoscale DiscussionSPCBuchanan, Dickenson, Wise, City of Norton62 min
Jul 24, 11:48 AM EDTMesoscale DiscussionSPCArlington, Clarke, Culpeper, Fairfax, Fauquier, Frederick and 22 more87 min
Jul 24, 12:33 PM EDTSevere Thunderstorm WatchSPCBuchanan, Dickenson, Lee, Russell, Scott, Washington and 3 more6 hr
Jul 24, 1:52 PM EDTMesoscale DiscussionSPCBuchanan, Dickenson, Wise, City of Norton53 min
Jul 24, 3:25 PM EDTMesoscale DiscussionSPCBuchanan, Dickenson, Lee, Russell, Scott, Smyth and 5 more95 min

Nearby

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