Alert archive / Virginia / Mesoscale Discussions in 2013

Mesoscale Discussion 1201

June 24, 20136 states

The Storm Prediction Center issued this mesoscale discussion at Jun 24, 2013, 1:48 PM EDT for 6 states. It was in force for 57 min.

The area

The outline as issued.

The facts

Issued: Jun 24, 2013, 1:48 PM EDT (17:48 UTC)
Expired: Jun 24, 2013, 2:45 PM EDT
In force: 57 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 51 counties

New Castle County, DE, Anne Arundel County, MD, Baltimore County, MD, Carroll County, MD, Cecil County, MD, Charles County, MD, City of Baltimore, MD, Frederick County, MD, Harford County, MD, Howard County, MD, Kent County, MD, Montgomery County, MD, Prince George's County, MD, Queen Anne's County, MD, Washington County, MD, Gloucester County, NJ, Salem County, NJ, Adams County, PA, Berks County, PA, Chester County, PA, Cumberland County, PA, Dauphin County, PA, Delaware County, PA, Franklin County, PA, Lancaster County, PA, Lebanon County, PA, Montgomery County, PA, Philadelphia County, PA, York County, PA, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Fredericksburg, 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, King George County, VA, Loudoun County, VA, Page County, VA, Prince William County, VA, Rappahannock County, VA, Stafford County, VA, Warren County, VA, Berkeley County, WV, Jefferson County, WV

The radar

The Sterling radar (KLWX), 79 km from the middle of the area, began a volume at 17:51 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 355Jun 24, 2:45 PM EDT

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 5.8 hours before the alert went out and 56 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: 705 J/kg
Mixed-layer CIN: -105 J/kg
Mixed-layer LCL: 1279 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 16 m²/s²
0-3 km storm-relative helicity: 55 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

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
Jun 24, 2:44 PM EDT	Severe Thunderstorm Watch	SPC	Kent, New Castle, Sussex	6 hr
Jun 24, 4:43 PM EDT	Mesoscale Discussion	SPC	Kent, New Castle	62 min

Nearby

Mesoscale Discussions in Virginia, 2013 Mesoscale Discussions in Maryland, 2013 Mesoscale Discussions in Pennsylvania, 2013 Every mesoscale discussion in 2013

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.