Alert archive / Virginia / Mesoscale Discussions in 2025

Mesoscale Discussion 694

May 5, 20254 states

The Storm Prediction Center issued this mesoscale discussion at May 5, 2025, 2:16 PM EDT for 4 states. It was in force for 119 min.

The area

The outline as issued.

The facts

Issued: May 5, 2025, 2:16 PM EDT (18:16 UTC)
Expired: May 5, 2025, 4:15 PM EDT
In force: 119 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch possible
Chance of a watch: 40%

All 43 counties

Allegany County, MD, Carroll County, MD, Frederick County, MD, Garrett County, MD, Howard County, MD, Montgomery County, MD, Prince George's County, MD, Washington County, MD, Adams County, PA, Bedford County, PA, Franklin County, PA, Fulton County, PA, Somerset County, PA, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Manassas, VA, City of Manassas Park, VA, City of Winchester, VA, Clarke County, VA, Culpeper County, VA, Fairfax County, VA, Fauquier County, VA, Frederick County, VA, Greene County, VA, Loudoun County, VA, Madison County, VA, Page County, VA, Prince William County, VA, Rappahannock County, VA, Shenandoah County, VA, Stafford County, VA, Warren County, VA, Berkeley County, WV, Grant County, WV, Hampshire County, WV, Hardy County, WV, Jefferson County, WV, Mineral County, WV, Morgan County, WV, Preston County, WV, Tucker County, WV

The radar

The Sterling radar (KLWX), 73 km from the middle of the area, began a volume at 18:18 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.

Severe Thunderstorm Watch 228May 5, 6:00 PM EDT

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 6.3 hours before the alert went out and 81 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: 192 J/kg
Mixed-layer CIN: -13 J/kg
Mixed-layer LCL: 586 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 29 m²/s²
0-3 km storm-relative helicity: 119 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

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
May 5, 5:29 PM EDT	Mesoscale Discussion	SPC	Anne Arundel, Calvert, Carroll, Charles, Dorchester, Frederick and 7 more	2 hr
May 5, 6:01 PM EDT	Severe Thunderstorm Watch	SPC	Anne Arundel, Baltimore, Calvert, Caroline, Carroll, Charles and 12 more	5 hr
May 5, 1:02 PM EDT	Mesoscale Discussion	SPC	Allegheny, Armstrong, Beaver, Butler, Clarion, Crawford and 8 more	118 min
May 5, 4:07 PM EDT	Severe Thunderstorm Watch	SPC	Allegheny, Beaver, Butler, Greene, Lawrence, Mercer and 2 more	5 hr
May 5, 12:05 PM EDT	Mesoscale Discussion	SPC	Albemarle, Amelia, Appomattox, Brunswick, Buckingham, Charlotte and 29 more	115 min
May 5, 1:24 PM EDT	Severe Thunderstorm Watch	SPC	Amelia, Brunswick, Caroline, Charles City, Chesterfield, Cumberland and 41 more	8 hr
May 5, 3:10 PM EDT	Mesoscale Discussion	SPC	Brunswick, Charles City, Chesterfield, Dinwiddie, Gloucester, Greensville and 17 more	2 hr
May 5, 6:07 PM EDT	Mesoscale Discussion	SPC	Isle of Wight, Southampton, Surry, Sussex, City of Chesapeake, City of Franklin and 2 more	113 min

Nearby

Mesoscale Discussions in Virginia, 2025 Mesoscale Discussions in West Virginia, 2025 Mesoscale Discussions in Maryland, 2025 Every mesoscale discussion in 2025

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.