Alert archive / North Carolina / Mesoscale Discussions in 2016
Mesoscale Discussion 539
The Storm Prediction Center issued this mesoscale discussion at May 3, 2016, 5:58 PM EDT for 30 counties in North Carolina; 17 counties in Virginia. It was in force for 62 min.
The area
The outline as issued.
The facts
- Issued
- May 3, 2016, 5:58 PM EDT (21:58 UTC)
- Expired
- May 3, 2016, 7:00 PM EDT
- In force
- 62 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 60%
All 47 counties
Beaufort County, NC, Bertie County, NC, Camden County, NC, Carteret County, NC, Chowan 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, Northampton County, NC, Onslow County, NC, Pamlico County, NC, Pasquotank County, NC, Perquimans County, NC, Pitt County, NC, Tyrrell County, NC, Warren County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC, City of Chesapeake, VA, City of Emporia, VA, City of Franklin, VA, City of Hampton, VA, City of Newport News, VA, City of Norfolk, VA, City of Poquoson, VA, City of Portsmouth, VA, City of Suffolk, VA, City of Virginia Beach, VA, Greensville County, VA, Isle of Wight County, VA, Northampton County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA, York County, VA
The radar
The Norfolk radar (KAKQ), 118 km from the middle of the area, began a volume at 22:01 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, 10.0 hours before the alert went out and 127 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
- 1655 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 539 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km storm-relative helicity
- 171 m²/s²
- 0-3 km storm-relative helicity
- 161 m²/s²
- Significant tornado parameter
- 1.1
- Supercell composite
- 6.5
The text
As transmitted.
912
ACUS11 KWNS 032159
SWOMCD
SPC MCD 032158
NCZ000-VAZ000-032300-
MESOSCALE DISCUSSION 0539
NWS STORM PREDICTION CENTER NORMAN OK
0458 PM CDT TUE MAY 03 2016
AREAS AFFECTED...SERN VA / NERN AND ERN NC
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 032158Z - 032300Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...WIDELY SCATTERED STORMS CAPABLE OF ISOLATED LARGE HAIL AND
DAMAGING GUSTS /50-65 MPH/ WILL BE POSSIBLE EARLY THIS EVENING.
DISCUSSION...21Z SUBJECTIVE SURFACE MESOANALYSIS PLACES A 1006-MB
LOW NEAR RIC WITH A COLD FRONT EXTENDING SWWD OVER THE WRN PART OF
THE CAROLINA PIEDMONT. A MOISTURE AXIS EXTENDS FROM CAPE FEAR NWD
INTO SERN VA WITH MID-UPPER 60S DEWPOINTS AMIDST MID 70S TEMPS.
VISIBLE SATELLITE IMAGERY SHOWS THIS PORTION OF NC/VA HAS BEEN
LARGELY VOID OF CLOUD COVER WITH THE EXCEPTION OF A BUBBLING CU
FIELD. AS AN UPPER TROUGH OVER THE OH VALLEY CONTINUES TO SLOWLY
PIVOT TOWARDS THE REGION...LARGE-SCALE FORCING FOR ASCENT WILL
BECOME MORE FAVORABLE FOR STORM DEVELOPMENT IN THE AREA.
OBJECTIVE ANALYSIS FIELDS SHOW THIS REGION OVER ERN NC/SERN VA HAS
BECOME WEAKLY TO MODERATELY UNSTABLE /500-1000 J PER KG MLCAPE/.
40-50 KT EFFECTIVE SHEAR WILL SUPPORT STORM ORGANIZATION...INCLUDING
THE POSSIBILITY FOR UPDRAFT ROTATION. AS SUCH...THE THREAT FOR
ISOLATED LARGE HAIL AND DAMAGING GUSTS WILL LIKELY INCREASE EARLY
THIS EVENING AS STORM ACTIVITY PUSHES EWD THROUGH THE REGION.
..SMITH/HART.. 05/03/2016
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...AKQ...MHX...RAH...ILM...
LAT...LON 34987832 36677808 37047718 37397629 37327583 35587538
35047574 34337707 34987832SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 3, 1:57 PM EDT | Mesoscale Discussion | SPC | Alamance, Alexander, Anson, Cabarrus, Caswell, Catawba and 35 more | 3 hr |
| May 3, 2:52 PM EDT | Severe Thunderstorm Watch | SPC | Alamance, Anson, Bladen, Brunswick, Cabarrus, Catawba and 40 more | 8 hr |
| May 3, 6:58 PM EDT | Severe Thunderstorm Watch | SPC | Beaufort, Bertie, Camden, Carteret, Chowan, Craven and 18 more | 4 hr |
| May 3, 3:48 PM EDT | Mesoscale Discussion | SPC | Albemarle, Amelia, Amherst, Appomattox, Bedford, Buckingham and 48 more | 117 min |
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.