Alert archive / Virginia / Mesoscale Discussions in 2026

Mesoscale Discussion 2005

August 16, 20269 counties in Maryland; Adams County, Cumberland County, York County, Pennsylvania; 39 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Aug 16, 2026, 7:00 PM EDT for 9 counties in Maryland; Adams County, Cumberland County, York County, Pennsylvania; 39 counties in Virginia. It was in force for 60 min.

The area

The outline as issued.

The facts

Issued: Aug 16, 2026, 7:00 PM EDT (23:00 UTC)
Expired: Aug 16, 2026, 8:00 PM EDT
In force: 60 min
Issued by: the Storm Prediction Center
Concerning: Severe thunderstorm watch 588

All 51 counties

Calvert County, MD, Carroll County, MD, Charles County, MD, City of Baltimore, MD, Frederick County, MD, Howard County, MD, Montgomery County, MD, Prince George's County, MD, Saint Mary's County, MD, Adams County, PA, Cumberland County, PA, York County, PA, Amelia County, VA, Arlington County, VA, Buckingham County, VA, Caroline County, VA, Charles City County, VA, Chesterfield County, VA, City of Alexandria, VA, City of Colonial Heights, VA, City of Fairfax, VA, City of Falls Church, VA, City of Fredericksburg, VA, City of Hopewell, VA, City of Manassas, VA, City of Manassas Park, VA, City of Petersburg, VA, City of Richmond, VA, Culpeper County, VA, Cumberland County, VA, Essex County, VA, Fairfax County, VA, Fauquier County, VA, Fluvanna County, VA, Goochland County, VA, Hanover County, VA, Henrico County, VA, James City County, VA, King and Queen County, VA, King George County, VA, King William County, VA, Loudoun County, VA, Louisa County, VA, New Kent County, VA, Orange County, VA, Powhatan County, VA, Prince William County, VA, Richmond County, VA, Spotsylvania County, VA, Stafford County, VA, Westmoreland County, VA

The radar

The Sterling radar (KLWX), 45 km from the middle of the area, began a volume at 23:01 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, 11.0 hours before the alert went out and 250 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: 334 J/kg
Mixed-layer CIN: -57 J/kg
Mixed-layer LCL: 630 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 78 m²/s²
0-3 km storm-relative helicity: 57 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 16, 3:28 PM EDT	Mesoscale Discussion	SPC	Allegany, Washington	2 hr
Aug 16, 4:36 PM EDT	Severe Thunderstorm Watch	SPC	Allegany, Carroll, Charles, Frederick, Garrett, Howard and 3 more	6 hr
Aug 16, 11:56 AM EDT	Mesoscale Discussion	SPC	Allegheny, Beaver, Butler, Greene, Lawrence, Washington	64 min
Aug 16, 1:05 PM EDT	Severe Thunderstorm Watch	SPC	Allegheny, Armstrong, Beaver, Butler, Clarion, Fayette and 9 more	9 hr
Aug 16, 2:28 PM EDT	Mesoscale Discussion	SPC	Allegheny, Armstrong, Beaver, Butler, Clarion, Fayette and 6 more	2 hr

Nearby

Mesoscale Discussions in Virginia, 2026 Mesoscale Discussions in Maryland, 2026 Mesoscale Discussions in Pennsylvania, 2026 Every mesoscale discussion in 2026

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.