Alert archive / Virginia / Mesoscale Discussions in 2025

Mesoscale Discussion 331

March 31, 202511 counties in Maryland; 56 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Mar 31, 2025, 6:31 PM EDT for 11 counties in Maryland; 56 counties in Virginia. It was in force for 119 min.

The area

The outline as issued.

The facts

Issued: Mar 31, 2025, 6:31 PM EDT (22:31 UTC)
Expired: Mar 31, 2025, 8:30 PM EDT
In force: 119 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch possible
Chance of a watch: 40%

All 67 counties

Anne Arundel County, MD, Calvert County, MD, Charles County, MD, Dorchester County, MD, Howard County, MD, Montgomery County, MD, Prince George's County, MD, Queen Anne's County, MD, Saint Mary's County, MD, Somerset County, MD, Talbot County, MD, Amelia County, VA, Arlington County, VA, Brunswick County, VA, Caroline County, VA, Charles City County, VA, Chesterfield County, VA, City of Alexandria, VA, City of Colonial Heights, VA, City of Emporia, VA, City of Fairfax, VA, City of Falls Church, VA, City of Franklin, VA, City of Fredericksburg, VA, City of Hampton, VA, City of Hopewell, VA, City of Manassas, VA, City of Manassas Park, 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, Dinwiddie County, VA, Essex County, VA, Fairfax County, VA, Gloucester County, VA, Goochland 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, Mathews County, VA, Middlesex County, VA, New Kent County, VA, Northumberland County, VA, Nottoway County, VA, Orange County, VA, Powhatan County, VA, Prince George County, VA, Prince William County, VA, Richmond County, VA, Southampton County, VA, Spotsylvania County, VA, Stafford County, VA, Surry County, VA, Sussex County, VA, Westmoreland County, VA, York County, VA

The radar

The Norfolk radar (KAKQ), 99 km from the middle of the area, began a volume at 22:31 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.5 hours before the alert went out and 123 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: 52 J/kg
Mixed-layer CIN: -70 J/kg
Mixed-layer LCL: 654 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 241 m²/s²
0-3 km storm-relative helicity: 252 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.8

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
Mar 31, 2:45 PM EDT	Mesoscale Discussion	SPC	Calvert, Charles, Dorchester, Saint Mary's, Somerset, Talbot and 1 more	2 hr
Mar 31, 3:33 PM EDT	Mesoscale Discussion	SPC	Baltimore, Carroll, Cecil, Frederick, Harford, Howard and 3 more	117 min
Mar 30, 10:20 PM EDT	Mesoscale Discussion	SPC	Buchanan, Dickenson, Lee, Russell, Scott, Wise and 1 more	2 hr
Mar 30, 10:56 PM EDT	Severe Thunderstorm Watch	SPC	Buchanan, Dickenson, Lee, Scott, Wise, City of Norton	6 hr
Mar 31, 2:17 AM EDT	Mesoscale Discussion	SPC	Buchanan, Dickenson, Lee, Russell, Scott, Tazewell and 4 more	88 min
Mar 31, 7:27 PM EDT	Mesoscale Discussion	SPC	Brunswick, Greensville, Southampton, Sussex, City of Emporia, City of Franklin	93 min

Nearby

Mesoscale Discussions in 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.