Alert archive / Virginia / Mesoscale Discussions in 2003

Mesoscale Discussion 1880

July 18, 2003Charles County, Maryland; 26 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Jul 18, 2003, 1:14 PM EDT for Charles County, Maryland; 26 counties in Virginia. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jul 18, 2003, 1:14 PM EDT (17:14 UTC)
Expired: Jul 18, 2003, 3:15 PM EDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 27 counties

Charles County, MD, Amelia County, VA, Appomattox County, VA, Buckingham County, VA, Campbell County, VA, Caroline County, VA, Charlotte County, VA, City of Charlottesville, VA, City of Fairfax, VA, City of Fredericksburg, VA, City of Lynchburg, VA, City of Manassas, VA, City of Manassas Park, VA, Cumberland County, VA, Fairfax County, VA, Fluvanna County, VA, Goochland County, VA, Halifax County, VA, Hanover County, VA, King George County, VA, Louisa County, VA, Orange County, VA, Powhatan County, VA, Prince Edward County, VA, Prince William County, VA, Spotsylvania County, VA, Stafford County, VA

The radar

The Norfolk radar (KAKQ), 148 km from the middle of the area, began a volume at 17:17 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

Roanoke, VA (KRNK), launched 12:00Z, 5.2 hours before the alert went out and 103 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: 179 J/kg
Mixed-layer CIN: -167 J/kg
Mixed-layer LCL: 939 m above ground
0-6 km bulk shear: 8 kt
0-1 km storm-relative helicity: 9 m²/s²
0-3 km storm-relative helicity: 17 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.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 18, 4:49 PM EDT	Mesoscale Discussion	SPC	Allegany, Garrett	116 min

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.