Alert archive / Maryland / Mesoscale Discussions in 2011

Mesoscale Discussion 1731

July 25, 20115 states

The Storm Prediction Center issued this mesoscale discussion at Jul 25, 2011, 1:12 PM EDT for 5 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jul 25, 2011, 1:12 PM EDT (17:12 UTC)
Expired: Jul 25, 2011, 3:15 PM EDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 32 counties

Kent County, DE, New Castle County, DE, Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Caroline County, MD, Carroll County, MD, Cecil 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, Talbot County, MD, Camden County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Berks County, PA, Bucks County, PA, Chester County, PA, Delaware County, PA, Lancaster County, PA, Montgomery County, PA, Philadelphia County, PA, York County, PA, Arlington County, VA, City of Alexandria, VA, City of Falls Church, VA

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 5.2 hours before the alert went out and 14 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: 481 J/kg
Mixed-layer CIN: -66 J/kg
Mixed-layer LCL: 760 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: -6 m²/s²
0-3 km storm-relative helicity: 24 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
Jul 25, 5:42 PM EDT	Mesoscale Discussion	SPC	Hunterdon, Morris, Warren	63 min
Jul 25, 11:12 AM EDT	Mesoscale Discussion	SPC	Butler, Cameron, Clarion, Crawford, Elk, Forest and 8 more	63 min
Jul 25, 11:37 AM EDT	Severe Thunderstorm Watch	SPC	Allegheny, Armstrong, Beaver, Bradford, Butler, Cameron and 31 more	7 hr
Jul 25, 3:16 PM EDT	Mesoscale Discussion	SPC	Allegheny, Armstrong, Beaver, Bradford, Butler, Cameron and 22 more	59 min
Jul 25, 7:23 PM EDT	Mesoscale Discussion	SPC	Brunswick, Charles City, Chesterfield, Dinwiddie, Gloucester, Greensville and 30 more	67 min

Nearby

Mesoscale Discussions in Maryland, 2011 Mesoscale Discussions in Pennsylvania, 2011 Mesoscale Discussions in New Jersey, 2011 Every mesoscale discussion in 2011

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.