Alert archive / Virginia / Mesoscale Discussions in 2005

Mesoscale Discussion 2513

November 29, 200510 counties in Maryland; 12 counties in North Carolina; 33 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Nov 29, 2005, 9:41 PM EST for 10 counties in Maryland; 12 counties in North Carolina; 33 counties in Virginia. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued: Nov 29, 2005, 9:41 PM EST (02:41 UTC)
Expired: Nov 29, 2005, 10:45 PM EST
In force: 64 min
Issued by: the Storm Prediction Center

All 55 counties

Calvert County, MD, Caroline County, MD, Dorchester County, MD, Kent County, MD, Queen Anne's County, MD, Saint Mary's County, MD, Somerset County, MD, Talbot County, MD, Wicomico County, MD, Worcester County, MD, Bertie County, NC, Camden County, NC, Chowan County, NC, Currituck County, NC, Edgecombe County, NC, Gates County, NC, Halifax County, NC, Hertford County, NC, Martin County, NC, Northampton County, NC, Pasquotank County, NC, Perquimans County, NC, Accomack County, VA, Charles City County, VA, City of Chesapeake, VA, City of Franklin, VA, City of Hampton, VA, City of Hopewell, 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, City of Williamsburg, VA, Essex County, VA, Gloucester County, VA, Henrico County, VA, Isle of Wight County, VA, James City County, VA, King and Queen 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 Norfolk radar (KAKQ), 51 km from the middle of the area, began a volume at 02:42 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

Wallops Is Stn, VA (KWAL), launched 00:00Z, 2.7 hours before the alert went out and 126 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 53 J/kg
Mixed-layer CIN: -93 J/kg
Mixed-layer LCL: 557 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 214 m²/s²
0-3 km storm-relative helicity: 234 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 300242
SWOMCD
SPC MCD 300241 
DEZ000-MDZ000-VAZ000-NCZ000-300345-

MESOSCALE DISCUSSION 2513
NWS STORM PREDICTION CENTER NORMAN OK
0841 PM CST TUE NOV 29 2005

AREAS AFFECTED...ERN VA...SRN MD

CONCERNING...TORNADO WATCH 887...

VALID 300241Z - 300345Z

SEVERE THREAT IS GRADUALLY DIMINISHING.

WATER VAPOR IMAGERY INDICATES THAT SHORTWAVE TROUGH WAS MOVING FROM
WV INTO PA AND MOST OF THE LIFT ASSOCIATED WITH THIS SYSTEM WAS
LIFTING NWD INTO PA AND NY. ALTHOUGH A NARROW LINE OF STORMS WAS
LOCATED ALONG THE COLD FRONT FROM SE OF DCA TO EAST OF RWI...THE
WEAKENING FORCING AND MARGINAL INSTABILITY HAS RESULTED IN THE STORM
INTENSITIES TO DECREASE DURING THE PAST HOUR.  ALTHOUGH AN ISOLATED
WIND SEVERE WIND GUST IS POSSIBLE WITH THE LINE...EVENING SOUNDINGS
SHOWED A STABLE BOUNDARY LAYER AND GIVEN THE WEAK INSTABILITY...IT
LIKELY WILL BECOME DIFFICULT FOR THE STRONG/SEVERE DOWNDRAFTS TO
REACH THE SURFACE.

..IMY.. 11/30/2005

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

ATTN...WFO...PHI...AKQ...MHX...LWX...RAH...

36557747 38007724 38837661 39337618 38647550 38357469
36507548 35967625 35737749 35797797

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Nov 29, 8:20 PM EST	Mesoscale Discussion	SPC	Charles, Saint Mary's	55 min

Nearby

Mesoscale Discussions in Virginia, 2005 Mesoscale Discussions in North Carolina, 2005 Mesoscale Discussions in Maryland, 2005 Every 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.