Alert archive / Virginia / Mesoscale Discussions in 2014

Mesoscale Discussion 733

May 27, 20146 states

The Storm Prediction Center issued this mesoscale discussion at May 27, 2014, 6:39 PM EDT for 6 states. It was in force for 36 min.

The area

The outline as issued.

The facts

Issued: May 27, 2014, 6:39 PM EDT (22:39 UTC)
Expired: May 27, 2014, 7:15 PM EDT
In force: 36 min
Issued by: the Storm Prediction Center

All 54 counties

Kent County, DE, New Castle County, DE, Sussex County, DE, Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Caroline County, MD, Cecil County, MD, Charles County, MD, City of Baltimore, MD, Dorchester County, MD, Harford County, MD, Howard County, MD, Kent County, MD, Montgomery County, MD, Prince George's County, MD, Queen Anne's County, MD, Talbot County, MD, Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Hunterdon County, NJ, Mercer County, NJ, Ocean County, NJ, Salem County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia 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, 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, Jefferson County, WV

The radar

The Dover AFB radar (KDOX), 90 km from the middle of the area, began a volume at 22:39 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

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 10.7 hours before the alert went out and 8 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: 1885 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 85 m²/s²
0-3 km storm-relative helicity: 94 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
May 27, 5:30 PM EDT	Severe Thunderstorm Watch	SPC	Kent, New Castle, Sussex	3 hr
May 27, 1:43 PM EDT	Mesoscale Discussion	SPC	Allegany, Carroll, Frederick, Garrett, Washington	62 min
May 27, 2:13 PM EDT	Severe Thunderstorm Watch	SPC	Allegany, Anne Arundel, Baltimore, Calvert, Caroline, Carroll and 14 more	8 hr
May 27, 3:02 PM EDT	Mesoscale Discussion	SPC	Bergen, Essex, Passaic	58 min
May 27, 5:48 PM EDT	Mesoscale Discussion	SPC	Amelia, Appomattox, Bedford, Buckingham, Campbell, Charlotte and 22 more	57 min

Nearby

Mesoscale Discussions in Virginia, 2014 Mesoscale Discussions in Maryland, 2014 Mesoscale Discussions in New Jersey, 2014 Every mesoscale discussion in 2014

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.