Alert archive / North Carolina / Mesoscale Discussions in 2012

Mesoscale Discussion 1336

July 1, 201243 counties in North Carolina; 21 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Jul 1, 2012, 2:53 PM EDT for 43 counties in North Carolina; 21 counties in Virginia. It was in force for 97 min.

The area

The outline as issued.

The facts

Issued
Jul 1, 2012, 2:53 PM EDT (18:53 UTC)
Expired
Jul 1, 2012, 4:30 PM EDT
In force
97 min
Issued by
the Storm Prediction Center
All 64 counties

Beaufort County, NC, Bertie County, NC, Bladen County, NC, Camden County, NC, Carteret County, NC, Chowan County, NC, Craven County, NC, Cumberland County, NC, Currituck County, NC, Dare County, NC, Duplin County, NC, Durham County, NC, Edgecombe County, NC, Franklin County, NC, Gates County, NC, Granville 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, Northampton County, NC, Onslow County, NC, Pamlico County, NC, Pasquotank County, NC, Pender County, NC, Perquimans County, NC, Pitt County, NC, Sampson County, NC, Tyrrell County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC, Brunswick County, VA, City of Chesapeake, VA, City of Colonial Heights, VA, City of Emporia, VA, City of Franklin, VA, City of Hopewell, VA, City of Newport News, VA, City of Norfolk, VA, City of Petersburg, VA, City of Portsmouth, VA, City of Suffolk, VA, City of Virginia Beach, VA, Dinwiddie County, VA, Greensville County, VA, Isle of Wight County, VA, Lunenburg County, VA, Mecklenburg County, VA, Prince George County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA

The radar

The Raleigh/Durham radar (KRAX), 87 km from the middle of the area, began a volume at 18:56 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

Newport, NC (KMHX), launched 12:00Z, 6.9 hours before the alert went out and 137 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 2012-07-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2962 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 2012-07-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 85 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
2962 J/kg
Mixed-layer CIN
-200 J/kg
Mixed-layer LCL
1419 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
85 m²/s²
0-3 km storm-relative helicity
66 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

590 
ACUS11 KWNS 011854
SWOMCD
SPC MCD 011853
NCZ000-VAZ000-012030-

MESOSCALE DISCUSSION 1336
NWS STORM PREDICTION CENTER NORMAN OK
0153 PM CDT SUN JUL 01 2012

AREAS AFFECTED...SERN VA...CNTRL/ERN NC

CONCERNING...SEVERE THUNDERSTORM WATCH 442...

VALID 011853Z - 012030Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 442
CONTINUES.

SUMMARY...PORTIONS OF WW 442 MAY NEED TO BE EXTENDED N/EWD IN SERN
VA. COVERAGE/INTENSITY OF THE SEVERE THREAT IN NC SHOULD INCREASE
DURING THE NEXT HOUR OR TWO.

DISCUSSION...PERSISTENT SMALL TSTM CLUSTER NOW APPROACHING THE
RDU/I-85 CORRIDOR IN N-CNTRL NC/S-CNTRL VA SHOULD CONTINUE ON A
GENERAL E/SEWD PROGRESSION...WHILE CONVECTION HAS BECOME SCATTERED
FARTHER S IN THE PIEDMONT TO COASTAL PLAIN. WITH ACTIVITY
APPROACHING/DEVELOPING WITHIN THE AXIS OF EXTREME INSTABILITY AMIDST
MID-LEVEL LAPSE RATES AROUND 8.5 TO 9 C/KM IN THE 18Z MHX/CHS
RAOBS...UPSCALE GROWTH IS LIKELY IMMINENT. THIS SHOULD YIELD
INCREASING COVERAGE/INTENSITY OF SEVERE WIND WITH EMBEDDED SEVERE
HAIL CORES.

..GRAMS.. 07/01/2012

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

ATTN...WFO...AKQ...MHX...RAH...ILM...RNK...

LAT...LON   37097819 37347737 37187657 36867605 35847555 35157555
            34547671 34357769 34507873 34827939 35357944 36287884
            37097819

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 1, 9:27 AM EDTMesoscale DiscussionSPCAlleghany, Ashe, Forsyth, Rockingham, Stokes, Surry and 3 more63 min
Jul 1, 9:44 AM EDTSevere Thunderstorm WatchSPCAlleghany, Ashe, Caswell, Rockingham, Stokes, Surry and 3 more5 hr
Jul 1, 11:38 AM EDTMesoscale DiscussionSPCAlamance, Alexander, Alleghany, Ashe, Avery, Caldwell and 12 more97 min
Jul 1, 12:56 PM EDTSevere Thunderstorm WatchSPCAlamance, Anson, Beaufort, Bertie, Camden, Carteret and 51 more7 hr
Jul 1, 1:39 PM EDTMesoscale DiscussionSPCAlexander, Anson, Buncombe, Burke, Cabarrus, Catawba and 24 more96 min
Jul 1, 2:01 PM EDTSevere Thunderstorm WatchSPCBladen, Brunswick, Cabarrus, Catawba, Cleveland, Columbus and 12 more9 hr
Jul 1, 4:15 PM EDTMesoscale DiscussionSPCBladen, Brunswick, Columbus, Duplin, New Hanover, Pender and 3 more90 min
Jul 1, 7:04 PM EDTMesoscale DiscussionSPCAlamance, Beaufort, Bertie, Camden, Carteret, Caswell and 40 more56 min
Jul 1, 7:39 PM EDTMesoscale DiscussionSPCAnson, Bladen, Brunswick, Cabarrus, Cleveland, Columbus and 14 more96 min

Nearby

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