Alert archive / Virginia / Mesoscale Discussions in 2019

Mesoscale Discussion 905

May 30, 2019Charles County, Saint Mary's County, Maryland; 12 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at May 30, 2019, 6:35 PM EDT for Charles County, Saint Mary's County, Maryland; 12 counties in Virginia. It was in force for 55 min.

The area

The outline as issued.

The facts

Issued: May 30, 2019, 6:35 PM EDT (22:35 UTC)
Expired: May 30, 2019, 7:30 PM EDT
In force: 55 min
Issued by: the Storm Prediction Center
Chance of a watch: 5%

Counties Charles County, MD, Saint Mary's County, MD, Caroline County, VA, City of Fredericksburg, VA, Culpeper County, VA, Greene County, VA, King George County, VA, Louisa County, VA, Madison County, VA, Orange County, VA, Prince William County, VA, Spotsylvania County, VA, Stafford County, VA, Westmoreland County, VA

The radar

The Sterling radar (KLWX), 76 km from the middle of the area, began a volume at 22:37 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, 10.6 hours before the alert went out and 76 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1213 m above ground
0-6 km bulk shear: 53 kt
0-1 km storm-relative helicity: -19 m²/s²
0-3 km storm-relative helicity: 36 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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 30, 12:15 PM EDT	Mesoscale Discussion	SPC	Anne Arundel, Baltimore, Calvert, Caroline, Carroll, Cecil and 15 more	2 hr
May 30, 2:01 PM EDT	Severe Thunderstorm Watch	SPC	Anne Arundel, Baltimore, Calvert, Caroline, Carroll, Cecil and 12 more	5 hr
May 30, 3:56 PM EDT	Mesoscale Discussion	SPC	Anne Arundel, Baltimore, Calvert, Caroline, Carroll, Cecil and 14 more	64 min
May 30, 1:45 PM EDT	Mesoscale Discussion	SPC	Bland, Buchanan, Dickenson, Giles, Lee, Russell and 3 more	2 hr

Nearby

Mesoscale Discussions in Virginia, 2019 Mesoscale Discussions in Maryland, 2019 Every mesoscale discussion in 2019

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.