Alert archive / North Carolina / Mesoscale Discussions in 2016

Mesoscale Discussion 1021

June 22, 201636 counties in North Carolina; 5 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Jun 22, 2016, 4:45 PM EDT for 36 counties in North Carolina; 5 counties in Virginia. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued
Jun 22, 2016, 4:45 PM EDT (20:45 UTC)
Expired
Jun 22, 2016, 6:15 PM EDT
In force
90 min
Issued by
the Storm Prediction Center
Chance of a watch
20%
All 41 counties

Alamance County, NC, Anson County, NC, Cabarrus County, NC, Caswell County, NC, Chatham County, NC, Cumberland County, NC, Davidson County, NC, Davie County, NC, Durham County, NC, Edgecombe County, NC, Forsyth County, NC, Franklin County, NC, Gaston County, NC, Granville County, NC, Guilford County, NC, Halifax County, NC, Harnett County, NC, Hoke County, NC, Johnston County, NC, Lee County, NC, Mecklenburg County, NC, Montgomery County, NC, Moore County, NC, Nash County, NC, Orange County, NC, Person County, NC, Randolph County, NC, Richmond County, NC, Rockingham County, NC, Rowan County, NC, Scotland County, NC, Stanly County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Wilson County, NC, Charlotte County, VA, City of Danville, VA, Halifax County, VA, Lunenburg County, VA, Mecklenburg County, VA

The radar

The Raleigh/Durham radar (KRAX), 89 km from the middle of the area, began a volume at 20:46 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, 8.8 hours before the alert went out and 47 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, Greensboro/Hi Pt, NC at 12:00Z on 2016-06-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 125 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Greensboro/Hi Pt, NC at 12:00Z on 2016-06-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 107 square meters per square second.1939587897Sfc1 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
125 J/kg
Mixed-layer CIN
-160 J/kg
Mixed-layer LCL
1103 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
107 m²/s²
0-3 km storm-relative helicity
111 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

637 
ACUS11 KWNS 222046
SWOMCD
SPC MCD 222045 
NCZ000-VAZ000-SCZ000-222215-

MESOSCALE DISCUSSION 1021
NWS STORM PREDICTION CENTER NORMAN OK
0345 PM CDT WED JUN 22 2016

AREAS AFFECTED...NORTH CAROLINA...SRN VIRGINIA PIEDMONT

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 222045Z - 222215Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...COVERAGE OF STORMS IS EXPECTED TO REMAIN RATHER
SPARSE...BUT ONE OR TWO STORMS MAY BE ACCOMPANIED BY A SEVERE
WIND/HAIL THREAT ACROSS PARTS OF THE NORTH CAROLINA AND VIRGINIA
PIEDMONT INTO COASTAL PLAIN LATE THIS AFTERNOON.

DISCUSSION...A SHORT WAVE TROUGH AND ASSOCIATED 50 KT WEST
NORTHWESTERLY 500 MB JET STREAK ARE IN THE PROCESS OF CROSSING THE
CENTRAL/SOUTHERN APPALACHIANS REGION.  ASSOCIATED FORCING FOR ASCENT
PROBABLY HAS AIDED THE INITIATION OF ISOLATED TO WIDELY SCATTERED
THUNDERSTORMS ACROSS THE PIEDMONT OF NORTH CAROLINA INTO SOUTHERN
VIRGINIA.  LOW-LEVEL LIFT APPEARS GENERALLY WEAK/UNFOCUSED ACROSS
THIS REGION...BUT INSOLATION HAS CONTRIBUTED TO FAIRLY DEEP BOUNDARY
LAYER MIXING AND AT LEAST MODEST BOUNDARY LAYER CAPE /1500+ J PER
KG/...IN THE PRESENCE OF STRENGTHENING VERTICAL SHEAR.  ONE OR TWO
STORMS COULD STILL INTENSIFY FURTHER THROUGH 22-23Z...WITH A
SUSTAINED SUPERCELL NOT OUT OF THE QUESTION.  GIVEN SIZABLE
LOW-LEVEL TEMPERATURE/DEW POINT SPREADS...LOCALLY STRONG SURFACE
GUSTS MAY BE THE PRIMARY SEVERE THREAT...WITH MARGINALLY SEVERE HAIL
ALSO POSSIBLE AS ACTIVITY SPREADS ACROSS THE REMAINDER OF THE
PIEDMONT TOWARD THE COASTAL PLAIN.

..KERR/GUYER.. 06/22/2016

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

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

LAT...LON   35338145 36308001 36897913 37137844 36627764 36047736
            35147840 34797933 35138126 35338145

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 21, 8:27 PM EDTMesoscale DiscussionSPCBuchanan, Dickenson, Lee, Russell, Scott, Smyth and 6 more63 min
Jun 22, 12:40 PM EDTMesoscale DiscussionSPCDickenson, Lee, Russell, Scott, Washington, Wise and 2 more2 hr

Nearby

Mesoscale Discussions in North Carolina, 2016Mesoscale Discussions in Virginia, 2016Every mesoscale discussion in 2016

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.