Alert archive / Virginia / Mesoscale Discussions in 2007

Mesoscale Discussion 822

May 16, 20077 states

The Storm Prediction Center issued this mesoscale discussion at May 16, 2007, 3:46 PM EDT for 7 states. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued: May 16, 2007, 3:46 PM EDT (19:46 UTC)
Expired: May 16, 2007, 5:15 PM EDT
In force: 89 min
Issued by: the Storm Prediction Center

All 91 counties

Kent County, DE, New Castle County, DE, Sussex County, DE, Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Caroline County, MD, Carroll County, MD, Cecil County, MD, Charles County, MD, City of Baltimore, MD, Dorchester County, 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, Saint Mary's County, MD, Talbot County, MD, Washington County, MD, Atlantic County, NJ, Bergen County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Essex County, NJ, Gloucester County, NJ, Hudson County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Ocean County, NJ, Passaic County, NJ, Salem County, NJ, Somerset County, NJ, Sussex County, NJ, Union County, NJ, Warren County, NJ, Bronx County, NY, Kings County, NY, New York County, NY, Queens County, NY, Richmond County, NY, Adams County, PA, Berks County, PA, Bucks County, PA, Carbon County, PA, Chester County, PA, Delaware County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Monroe County, PA, Montgomery County, PA, Northampton County, PA, Philadelphia County, PA, Pike County, PA, Schuylkill County, PA, York County, PA, Arlington County, VA, Caroline 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, Essex County, VA, Fairfax County, VA, Fauquier County, VA, Frederick County, VA, King George County, VA, Loudoun County, VA, Orange County, VA, Prince William County, VA, Rappahannock County, VA, Richmond County, VA, Spotsylvania County, VA, Stafford County, VA, Warren County, VA, Westmoreland County, VA, Berkeley County, WV, Jefferson County, WV

The radar

The Dover AFB radar (KDOX), 105 km from the middle of the area, began a volume at 19:47 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, 7.8 hours before the alert went out and 40 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: 18 J/kg
Mixed-layer CIN: -160 J/kg
Mixed-layer LCL: 1421 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 107 m²/s²
0-3 km storm-relative helicity: 138 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 16, 12:56 PM EDT	Mesoscale Discussion	SPC	New Castle	64 min
May 16, 1:26 PM EDT	Severe Thunderstorm Watch	SPC	Kent, New Castle, Sussex	7 hr
May 16, 11:57 AM EDT	Mesoscale Discussion	SPC	Bergen, Morris, Passaic, Sussex, Warren	93 min
May 16, 12:32 PM EDT	Tornado Watch	SPC	Columbia, Dutchess, Orange, Putnam, Rockland, Ulster and 1 more	6 hr
May 16, 2:43 PM EDT	Mesoscale Discussion	SPC	Columbia, Dutchess, Orange, Putnam, Rensselaer, Rockland and 3 more	92 min
May 16, 12:46 AM EDT	Mesoscale Discussion	SPC	Allegheny, Beaver, Butler, Lawrence, Washington	59 min

Nearby

Mesoscale Discussions in Virginia, 2007 Mesoscale Discussions in New Jersey, 2007 Mesoscale Discussions in Maryland, 2007 Every mesoscale discussion in 2007

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.