Alert archive / Virginia / Mesoscale Discussions in 2016

Mesoscale Discussion 532

May 2, 20165 states

The Storm Prediction Center issued this mesoscale discussion at May 2, 2016, 1:34 PM EDT for 5 states. It was in force for 116 min.

The area

The outline as issued.

The facts

Issued
May 2, 2016, 1:34 PM EDT (17:34 UTC)
Expired
May 2, 2016, 3:30 PM EDT
In force
116 min
Issued by
the Storm Prediction Center
Chance of a watch
40%
All 122 counties

Bell County, KY, Harlan County, KY, Letcher County, KY, Pike County, KY, Alexander County, NC, Alleghany County, NC, Ashe County, NC, Avery County, NC, Buncombe County, NC, Burke County, NC, Caldwell County, NC, Forsyth County, NC, Haywood County, NC, Madison County, NC, McDowell County, NC, Mitchell County, NC, Rockingham County, NC, Stokes County, NC, Surry County, NC, Swain County, NC, Watauga County, NC, Wilkes County, NC, Yadkin County, NC, Yancey County, NC, Anderson County, TN, Blount County, TN, Carter County, TN, Claiborne County, TN, Cocke County, TN, Grainger County, TN, Greene County, TN, Hamblen County, TN, Hancock County, TN, Hawkins County, TN, Jefferson County, TN, Johnson County, TN, Knox County, TN, Sevier County, TN, Sullivan County, TN, Unicoi County, TN, Union County, TN, Washington County, TN, Albemarle County, VA, Alleghany County, VA, Amelia County, VA, Amherst County, VA, Appomattox County, VA, Augusta County, VA, Bath County, VA, Bedford County, VA, Bland County, VA, Botetourt County, VA, Buchanan County, VA, Buckingham County, VA, Campbell County, VA, Carroll County, VA, Charlotte County, VA, City of Bristol, VA, City of Buena Vista, VA, City of Charlottesville, VA, City of Covington, VA, City of Danville, VA, City of Galax, VA, City of Harrisonburg, VA, City of Lexington, VA, City of Lynchburg, VA, City of Martinsville, VA, City of Norton, VA, City of Radford, VA, City of Roanoke, VA, City of Salem, VA, City of Staunton, VA, City of Waynesboro, VA, Craig County, VA, Cumberland County, VA, Dickenson County, VA, Floyd County, VA, Fluvanna County, VA, Franklin County, VA, Giles County, VA, Goochland County, VA, Grayson County, VA, Greene County, VA, Halifax County, VA, Henry County, VA, Highland County, VA, Lee County, VA, Louisa County, VA, Madison County, VA, Montgomery County, VA, Nelson County, VA, Nottoway County, VA, Orange County, VA, Page County, VA, Patrick County, VA, Pittsylvania County, VA, Powhatan County, VA, Prince Edward County, VA, Pulaski County, VA, Roanoke County, VA, Rockbridge County, VA, Rockingham County, VA, Russell County, VA, Scott County, VA, Smyth County, VA, Tazewell County, VA, Washington County, VA, Wise County, VA, Wythe County, VA, Fayette County, WV, Greenbrier County, WV, Logan County, WV, McDowell County, WV, Mercer County, WV, Mingo County, WV, Monroe County, WV, Nicholas County, WV, Pendleton County, WV, Pocahontas County, WV, Raleigh County, WV, Summers County, WV, Wyoming County, WV

The radar

The Roanoke radar (KFCX), 63 km from the middle of the area, began a volume at 17:36 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

Roanoke, VA (KRNK), launched 12:00Z, 5.6 hours before the alert went out and 132 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, Roanoke, VA at 12:00Z on 2016-05-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 215 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, Roanoke, VA at 12:00Z on 2016-05-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 115 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
215 J/kg
Mixed-layer CIN
-41 J/kg
Mixed-layer LCL
706 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
115 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

358 
ACUS11 KWNS 021735
SWOMCD
SPC MCD 021734 
VAZ000-NCZ000-WVZ000-TNZ000-KYZ000-021930-

MESOSCALE DISCUSSION 0532
NWS STORM PREDICTION CENTER NORMAN OK
1234 PM CDT MON MAY 02 2016

AREAS AFFECTED...ERN TN...ERN KY...SERN WV...NWRN NC AND WRN VA

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 021734Z - 021930Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...THUNDERSTORMS WILL CONTINUE TO INCREASE IN COVERAGE AND
INTENSITY THIS AFTERNOON OVER THE SRN APPALACHIANS INTO THE MIDDLE
ATLANTIC REGION. MULTICELL AND MARGINAL SUPERCELL STRUCTURES ARE
EXPECTED WITH ISOLATED LARGE HAIL AND DOWNBURST WINDS THE MAIN
THREATS. TRENDS ARE BEING MONITORED FOR A SEVERE THUNDERSTORM WATCH.

DISCUSSION...THIS AFTERNOON NUMEROUS THUNDERSTORMS ARE DEVELOPING 
OVER THE SRN APPALACHIAN REGION FROM ERN TN THROUGH ERN KY...WRN VA
AND SRN WV. MORNING RAOB DATA SHOWED MINIMAL CAPPING OF THE BOUNDARY
LAYER AS TEMPERATURES RISE THROUGH THE 70S...AND CONTINUED HEATING
OVER THE HIGHER TERRAIN WILL PROMOTE ADDITIONAL THUNDERSTORM
INITIATION. THE LATEST OBJECTIVE ANALYSIS INDICATES THE ATMOSPHERE
TO BE MODERATELY UNSTABLE WITH 1000-1500 J/KG MLCAPE AND MODEST
/6.5-7 C/KM MID LEVEL LAPSE RATES. A BELT OF MODEST WSWLY WINDS
ALOFT DOWNSTREAM FROM A PROGRESSIVE UPPER TROUGH OVER THE MID MS
VALLEY REGION IS CONTRIBUTING TO 30-40 KT EFFECTIVE BULK SHEAR. THIS
ENVIRONMENT WILL SUPPORT BOTH MULTICELL STORM MODES AS WELL AS A FEW
MARGINAL SUPERCELL STRUCTURES CAPABLE OF A FEW INSTANCES OF LARGE
HAIL AND DOWNBURST WINDS.

..DIAL/THOMPSON.. 05/02/2016

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

ATTN...WFO...AKQ...LWX...RAH...RNK...RLX...GSP...MRX...JKL...

LAT...LON   36098448 37568268 38687993 38687831 37937774 37127797
            36177982 35318342 36098448

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 1, 9:21 PM EDTMesoscale DiscussionSPCBoone, Campbell, Kenton114 min
May 2, 2:17 PM EDTSevere Thunderstorm WatchSPCBell, Breathitt, Clay, Floyd, Harlan, Johnson and 10 more8 hr
May 2, 2:43 PM EDTMesoscale DiscussionSPCBertie, Chatham, Cumberland, Duplin, Durham, Edgecombe and 23 more62 min
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 Virginia, 2016Mesoscale Discussions in North Carolina, 2016Mesoscale Discussions in Tennessee, 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.