Alert archive / Virginia / Mesoscale Discussions in 2003

Mesoscale Discussion 2008

July 28, 20037 counties in Maryland; 54 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Jul 28, 2003, 5:41 PM EDT for 7 counties in Maryland; 54 counties in Virginia. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jul 28, 2003, 5:41 PM EDT (21:41 UTC)
Expired: Jul 28, 2003, 7:45 PM EDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 61 counties

Calvert County, MD, Charles County, MD, Dorchester County, MD, Saint Mary's County, MD, Somerset County, MD, Wicomico County, MD, Worcester County, MD, Accomack County, VA, Amelia County, VA, Brunswick County, VA, Caroline County, VA, Charles City County, VA, Chesterfield County, VA, City of Colonial Heights, VA, City of Emporia, VA, City of Franklin, VA, City of Fredericksburg, 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 Williamsburg, VA, Cumberland County, VA, Dinwiddie County, VA, Essex County, VA, Fluvanna County, VA, Gloucester County, VA, Goochland 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, Louisa County, VA, Lunenburg County, VA, Mathews County, VA, Middlesex County, VA, New Kent County, VA, Northampton County, VA, Northumberland County, VA, Nottoway County, VA, Orange County, VA, Powhatan County, VA, Prince Edward County, VA, Prince George County, VA, Richmond County, VA, Southampton County, VA, Spotsylvania County, VA, Surry County, VA, Sussex County, VA, Westmoreland County, VA, York County, VA

The radar

The Norfolk radar (KAKQ), 61 km from the middle of the area, began a volume at 21:42 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 12:00Z, 9.7 hours before the alert went out and 185 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: 1641 J/kg
Mixed-layer CIN: -22 J/kg
Mixed-layer LCL: 763 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 50 m²/s²
0-3 km storm-relative helicity: 65 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

395 
ACUS11 KWNS 282141
SWOMCD
SPC MCD 282141 
DEZ000-MDZ000-VAZ000-282345-

MESOSCALE DISCUSSION 2008
NWS STORM PREDICTION CENTER NORMAN OK
0441 PM CDT MON JUL 28 2003

AREAS AFFECTED...CENTRAL VA/SRN MD AND THE DELMARVA PENINSULA

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 282141Z - 282345Z

ISOLATED SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS/MARGINALLY SEVERE HAIL WILL CONTINUE TO FORM AND MOVE EWD FROM
CENTRAL VA INTO THE DELMARVA PENINSULA OVER THE NEXT FEW HOURS. A WW
IS NOT ANTICIPATED AT THIS TIME DUE TO LIMITED EXPECTED THREAT.

LATEST WV IMAGERY INDICATES A SUBTLE VORTICITY CENTER MOVING ACROSS
ERN WV AND WRN VA. STRONGER THAN FORECAST MID LEVEL WINDS WERE
OBSERVED FROM REGIONAL VWP/S WITH 30-35 KTS OBSERVED ON THE VWP FROM
CHARLESTON WV AND STERLING VA IN ASSOCIATION WITH THIS VORT MAX.
STRONGEST MID LEVEL FORCING WILL CONTINUE TO AID IN A LINE OF
THUNDERSTORMS OVER CENTRAL VA IN THE NEXT HOUR. SUFFICIENT DEEP
LAYER SHEAR WILL EXIST FOR SOME STORM ROTATION WITH THE THREAT FOR
HAIL/LOCALLY DAMAGING WINDS. SOUTH OF A STATIONARY BOUNDARY
EXTENDING FROM NEAR CHO EWD INTO 25 NE SBY MODERATE INSTABILITY WITH
MLCAPES AROUND 2000 J/KG EXISTED. DESPITE THIS INSTABILITY
RELATIVELY WEAK LAPSE RATES AROUND 6 DEG C/KM IN THE LOW TO MID
LEVELS WILL LIMIT THE THREAT FOR ORGANIZED DAMAGING WIND THREAT.

..CROSBIE.. 07/28/2003

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

ATTN...WFO...PHI...AKQ...LWX...RNK...

36997848 38157842 38687646 38467512 36707621 36627769
36837841

Nearby

Mesoscale Discussions in Virginia, 2003 Mesoscale Discussions in Maryland, 2003 Every mesoscale discussion in 2003

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.