Alert archive / Virginia / Mesoscale Discussions in 2005

Mesoscale Discussion 968

May 23, 20054 states

The Storm Prediction Center issued this mesoscale discussion at May 23, 2005, 1:16 PM EDT for 4 states. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued
May 23, 2005, 1:16 PM EDT (17:16 UTC)
Expired
May 23, 2005, 2:45 PM EDT
In force
89 min
Issued by
the Storm Prediction Center
All 87 counties

Saint Mary's County, MD, Beaufort County, NC, Bertie County, NC, Bladen County, NC, Brunswick County, NC, Camden County, NC, Chowan County, NC, Columbus County, NC, Craven County, NC, Currituck County, NC, Duplin County, NC, Edgecombe County, NC, Gates County, NC, Greene County, NC, Halifax County, NC, Hertford 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, Robeson County, NC, Sampson County, NC, Tyrrell County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC, Berkeley County, SC, Clarendon County, SC, Dillon County, SC, Dorchester County, SC, Florence County, SC, Georgetown County, SC, Horry County, SC, Marion County, SC, Orangeburg County, SC, Williamsburg County, SC, Brunswick County, VA, Caroline County, VA, Charles City County, VA, Chesterfield County, VA, City of Chesapeake, VA, City of Colonial Heights, VA, City of Emporia, VA, City of Franklin, VA, City of Hampton, VA, City of Hopewell, VA, City of Newport News, VA, City of Norfolk, VA, City of Petersburg, VA, City of Poquoson, VA, City of Portsmouth, VA, City of Richmond, VA, City of Suffolk, VA, City of Virginia Beach, VA, City of Williamsburg, VA, Dinwiddie County, VA, Essex County, VA, Gloucester County, VA, Greensville County, VA, Hanover County, VA, Henrico County, VA, Isle of Wight County, VA, James City County, VA, King and Queen County, VA, King George County, VA, King William County, VA, Lancaster County, VA, Mathews County, VA, Middlesex County, VA, New Kent County, VA, Northampton County, VA, Northumberland County, VA, Prince George County, VA, Richmond County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA, Westmoreland County, VA, York County, VA

The radar

The Raleigh/Durham radar (KRAX), 41 km from the middle of the area, began a volume at 17:15 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, 5.3 hours before the alert went out and 153 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, Newport, NC at 12:00Z on 2005-05-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 101 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, Newport, NC at 12:00Z on 2005-05-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 187 square meters per square second.1939587897117Sfc1 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
101 J/kg
Mixed-layer CIN
-43 J/kg
Mixed-layer LCL
735 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
187 m²/s²
0-3 km storm-relative helicity
239 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.6

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
ACUS11 KWNS 231716
SWOMCD
SPC MCD 231716 
VAZ000-NCZ000-MDZ000-SCZ000-231845-

MESOSCALE DISCUSSION 0968
NWS STORM PREDICTION CENTER NORMAN OK
1216 PM CDT MON MAY 23 2005

AREAS AFFECTED...ERN VA AND PORTIONS OF ERN NC/SC

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 231716Z - 231845Z

THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS PORTIONS OF ERN VA SWD
ACROSS THE ERN CAROLINAS WITH A POTENTIAL FOR DAMAGING WINDS. AREA
IS BEING MONITORED FOR A POSSIBLE WW.

WEAK SURFACE LOW WAS LOCATED IN SOUTH CENTRAL VA IN THE LYH AREA
WITH A LEESIDE TROUGH EXTENDING SWD FROM THE LOW NEAR A RDU-FAY-AGS
LINE. AIR MASS IS BECOMING MODERATELY UNSTABLE TO THE EAST OF THE
BOUNDARY...WITH DRIER AIR MOVING IN FROM THE WEST.

A 7OKT MID LEVEL JET IS ALSO PUSHING INTO THE AREA...WITH THE
STRONGEST FORCING FOR CONVECTION LOCATED ACROSS ERN VA. HOWEVER...
INSTABILITY IS STRONGER ACROSS THE ERN CAROLINAS WHERE DEWPOINTS ARE
IN THE LOWER/MID 60S. ALTHOUGH LOW LEVEL CONVERGENCE IS
WEAK...STRONGER CONVERGENCE NEAR THE INTERSECTION OF AN OLD OUTFLOW
BOUNDARY AND THE LEESIDE TROUGH...S OF FLO...IS AIDING IN CUMULUS
ENHANCEMENT. WITH THE WEAK CAP...EXPECT THESE CLOUDS TO DEVELOP INTO
STORMS SHORTLY...WITH OTHERS POSSIBLY DEVELOPING ALONG AND EAST OF
THE SURFACE LOW/TROUGH LATER IN THE AFTERNOON.

DEEP LAYER SHEAR AT 50-60 KT WOULD AID IN STORM ORGANIZATION. IF
STORMS DEVELOP...THE STRONG TROPOSPHERIC WINDS AND STEEP LOW LEVEL
LAPSE RATES WOULD BE FAVORABLE FOR A DAMAGING WIND THREAT. WEAK
CONVERGENCE MAY LIMIT COVERAGE...SO STILL SOME QUESTION WHETHER
ENOUGH COVERAGE WILL DEVELOP FOR A WW ISSUANCE.

..IMY.. 05/23/2005

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

ATTN...WFO...AKQ...MHX...LWX...RAH...ILM...CHS...CAE...

33378094 34297983 35487825 36797787 38187742 38647673
37867579 36067569 34057761 32897973 32628049

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 23, 3:50 PM EDTSevere Thunderstorm WatchSPCCharles6 hr
May 23, 5:12 PM EDTMesoscale DiscussionSPCCharles93 min
May 23, 5:36 PM EDTMesoscale DiscussionSPCCharles84 min
May 23, 6:42 PM EDTMesoscale DiscussionSPCAmelia, Cumberland, Dinwiddie, Fluvanna, Goochland, Greensville and 7 more63 min

Nearby

Mesoscale Discussions in Virginia, 2005Mesoscale Discussions in North Carolina, 2005Mesoscale Discussions in South Carolina, 2005Every mesoscale discussion in 2005

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.