Alert archive / North Carolina / Mesoscale Discussions in 2016

Mesoscale Discussion 534

May 2, 201629 counties in North Carolina; 27 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at May 2, 2016, 2:43 PM EDT for 29 counties in North Carolina; 27 counties in Virginia. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued
May 2, 2016, 2:43 PM EDT (18:43 UTC)
Expired
May 2, 2016, 3:45 PM EDT
In force
62 min
Issued by
the Storm Prediction Center
Chance of a watch
40%
All 56 counties

Bertie County, NC, Chatham County, NC, Cumberland County, NC, Duplin County, NC, Durham County, NC, Edgecombe County, NC, Franklin County, NC, Granville County, NC, Greene County, NC, Halifax County, NC, Harnett County, NC, Hertford County, NC, Hoke County, NC, Johnston County, NC, Lee County, NC, Lenoir County, NC, Martin County, NC, Moore County, NC, Nash County, NC, Northampton County, NC, Orange County, NC, Pitt County, NC, Sampson County, NC, Scotland County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Wayne County, NC, Wilson County, NC, Amelia County, VA, Brunswick County, VA, Charles City County, VA, Chesterfield County, VA, City of Colonial Heights, VA, City of Emporia, VA, City of Franklin, VA, City of Hopewell, VA, City of Petersburg, VA, City of Richmond, VA, City of Suffolk, VA, City of Williamsburg, VA, Dinwiddie County, VA, Greensville County, VA, Hanover County, VA, Henrico County, VA, Isle of Wight County, VA, James City County, VA, Lunenburg County, VA, Mecklenburg County, VA, New Kent County, VA, Nottoway County, VA, Powhatan County, VA, Prince George County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA

The radar

The Raleigh/Durham radar (KRAX), 71 km from the middle of the area, began a volume at 18:46 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 6.7 hours before the alert went out and 151 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 2016-05-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 670 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, Greensboro/Hi Pt, NC at 12:00Z on 2016-05-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 62 square meters per square second.19395878Sfc1 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
670 J/kg
Mixed-layer CIN
-73 J/kg
Mixed-layer LCL
787 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
62 m²/s²
0-3 km storm-relative helicity
45 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

As transmitted.

000 
ACUS11 KWNS 021843
SWOMCD
SPC MCD 021843 
VAZ000-NCZ000-021945-

MESOSCALE DISCUSSION 0534
NWS STORM PREDICTION CENTER NORMAN OK
0143 PM CDT MON MAY 02 2016

AREAS AFFECTED...CNTRL/ERN NC...S-CNTRL/SE VA

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 021843Z - 021945Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...DAMAGING WIND GUSTS AND ISOLATED SVR HAIL ARE POSSIBLE AS
STORM COVERAGE INCREASES THIS AFTERNOON. TRENDS WILL BE MONITORED
FOR A POSSIBLE WW.

DISCUSSION...RECENT OBSERVATIONS REVEAL TEMPERATURES HAVE CLIMBED
INTO THE UPPER 70S AND LOW 80S UNDER MOSTLY CLEAR SKIES. THESE
SURFACE TEMPERATURES COUPLED WITH GOOD LOW-LEVEL MOISTURE /DEWPOINTS
IN THE MID 60S/ ARE SUPPORTING MLCAPE AROUND 1500-2000 J PER KG.
BOUNDARY LAYER MIXING IS EXPECTED TO KEEP INSTABILITY CLOSE TO
CURRENTLY OBSERVED VALUES DESPITE PERSISTENT HEATING. HOWEVER...THE
CONTINUED MIXING AND RESULTING STEEP LOW-LEVEL LAPSE RATES WILL
CREATE AN ENVIRONMENT FAVORABLE FOR DAMAGING WIND
GUSTS...PARTICULARLY ACROSS SRN VA WHERE THE TEMPERATURE-DEWPOINTS
SPREADS WILL BE GREATER. SOME HAIL IS ALSO POSSIBLE WITH THE
STRONGEST UPDRAFTS BUT THE AREA IS EXPECTED TO REMAIN ON THE SRN
FRINGE OF THE BETTER FLOW ALOFT...LIMITING STORM ORGANIZATION AND
SUSTAINED UPDRAFT STRENGTH. CONVECTIVE TRENDS ACROSS THE REGION WILL
BE MONITORED FOR A POSSIBLE WW.

..MOSIER/DIAL.. 05/02/2016

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

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

LAT...LON   36877845 37837776 37647682 36887652 35117745 34607865
            34907970 35617978 36437878 36877845

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 2, 1:34 PM EDTMesoscale DiscussionSPCAlexander, Alleghany, Ashe, Avery, Buncombe, Burke and 14 more116 min
May 2, 2:17 PM EDTSevere Thunderstorm WatchSPCAlexander, Alleghany, Ashe, Avery, Buncombe, Burke and 16 more8 hr
May 2, 5:38 PM EDTSevere Thunderstorm WatchSPCBertie, Gates, Hertford, Northampton5 hr
May 2, 6:34 PM EDTMesoscale DiscussionSPCAlbemarle, Amelia, Appomattox, Arlington, Brunswick, Buckingham and 47 more56 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.