Alert archive / North Carolina / Mesoscale Discussions in 2012
Mesoscale Discussion 767
The Storm Prediction Center issued this mesoscale discussion at May 9, 2012, 5:36 PM EDT for 35 counties in North Carolina. It was in force for 84 min.
The area
The outline as issued.
The facts
- Issued
- May 9, 2012, 5:36 PM EDT (21:36 UTC)
- Expired
- May 9, 2012, 7:00 PM EDT
- In force
- 84 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
All 35 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, Currituck County, NC, Dare County, NC, Duplin County, NC, Edgecombe County, NC, Gates County, NC, Greene County, NC, Halifax County, NC, Hertford County, NC, Hyde County, NC, Jones 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, Sampson County, NC, Tyrrell County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC
The radar
The Morehead City radar (KMHX), 75 km from the middle of the area, began a volume at 21:37 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, 9.6 hours before the alert went out and 74 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.
- Mixed-layer CAPE
- 598 J/kg
- Mixed-layer CIN
- -1 J/kg
- Mixed-layer LCL
- 519 m above ground
- 0-6 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- 78 m²/s²
- 0-3 km storm-relative helicity
- 73 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
788
ACUS11 KWNS 092136
SWOMCD
SPC MCD 092136
NCZ000-092300-
MESOSCALE DISCUSSION 0767
NWS STORM PREDICTION CENTER NORMAN OK
0436 PM CDT WED MAY 09 2012
AREAS AFFECTED...ERN NC
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 092136Z - 092300Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...AN ISOLATED THREAT FOR SVR STORMS WITH MARGINALLY SVR WIND
GUSTS WILL EXIST INTO EARLY EVENING ACROSS PORTIONS OF ERN NC.
DISCUSSION...INCREASING LARGE-SCALE DCVA AHEAD OF A SHORTWAVE TROUGH
EXTENDING FROM THE GREAT LAKES SWD INTO THE TN VALLEY
REGION...AUGMENTED BY THE INFLUENCE OF A LEADING IMPULSE CROSSING
PARTS OF THE MID-ATLANTIC...CONTINUES TO FOSTER AN ENVIRONMENT
FAVORABLE FOR CONVECTION AHEAD OF A COLD FRONT PRESENTLY CROSSING
PARTS OF CNTRL NC. A BROKEN SQUALL LINE EXTENDS SOUTH FROM NEAR
ROANOKE RAPIDS NC INTO NERN SC...WITH ADDITIONAL SEMI-DISCRETE
CONVECTIVE ELEMENTS EAST OF THIS LINE. THE SQUALL LINE IS EXPECTED
TO CONTINUE MOVING EWD AROUND 30-35 MPH INTO EARLY EVENING WHILE
APPROACHING THE OUTER BANKS...AMIDST FAIRLY RICH LOW-LEVEL MOISTURE
/SFC DEWPOINTS IN THE LOWER AND MIDDLE 60S/. OCCASIONALLY ORGANIZED
STORM STRUCTURES HAVE BEEN NOTED IN ASSOCIATION WITH THE SQUALL LINE
ACROSS PORTIONS OF CNTRL NC PER RALEIGH WSR-88D DATA...OWING TO
MODEST DEEP-LAYER SHEAR GIVEN AROUND 30-40 KT OF MID-LEVEL SWLY FLOW
PER AREA VWP DATA. SPORADIC INSTANCES OF MARGINALLY SVR WIND GUSTS
WILL BE THE PRIMARY CONCERN...PARTICULARLY IN ASSOCIATION WITH ANY
BOWING/LEWP STRUCTURES EMBEDDED WITHIN THE SQUALL LINE.
HOWEVER...WITH ONLY MARGINAL INSTABILITY AHEAD OF THE LINE OWING TO
EXTENSIVE CLOUD COVERAGE AND WEAK MID-LEVEL LAPSE RATES /MLCAPE
VALUES AROUND 500 J PER KG/...OVERALL CONVECTIVE VIGOR WILL LIKELY
BE SUPPRESSED.
..COHEN/HART.. 05/09/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...AKQ...MHX...RAH...ILM...
LAT...LON 35627829 36377793 36497701 36387556 35497536 34777620
33937779 33857834 34247887 34817863 35627829SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 9, 11:32 AM EDT | Mesoscale Discussion | SPC | Anson, Cumberland, Hoke, Montgomery, Moore, Richmond and 4 more | 88 min |
Nearby
Mesoscale Discussions in North 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.