Alert archive / Pennsylvania / Mesoscale Discussions in 2011

Mesoscale Discussion 812

May 19, 20115 states

The Storm Prediction Center issued this mesoscale discussion at May 19, 2011, 2:17 PM EDT for 5 states. It was in force for 58 min.

The area

The outline as issued.

The facts

Issued
May 19, 2011, 2:17 PM EDT (18:17 UTC)
Expired
May 19, 2011, 3:15 PM EDT
In force
58 min
Issued by
the Storm Prediction Center
All 75 counties

Kent County, DE, New Castle County, DE, Baltimore County, MD, Cecil County, MD, Harford County, MD, Kent County, MD, Atlantic County, NJ, Bergen County, NJ, Burlington County, NJ, Camden County, NJ, Cumberland County, NJ, Essex County, NJ, Gloucester County, NJ, Hudson County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Morris County, NJ, Passaic County, NJ, Salem County, NJ, Somerset County, NJ, Sussex County, NJ, Union County, NJ, Warren County, NJ, Albany County, NY, Broome County, NY, Chemung County, NY, Chenango County, NY, Cortland County, NY, Delaware County, NY, Greene County, NY, Montgomery County, NY, New York County, NY, Orange County, NY, Otsego County, NY, Richmond County, NY, Rockland County, NY, Schenectady County, NY, Schoharie County, NY, Schuyler County, NY, Steuben County, NY, Sullivan County, NY, Tioga County, NY, Tompkins County, NY, Ulster County, NY, Yates County, NY, Berks County, PA, Bradford County, PA, Bucks County, PA, Carbon County, PA, Chester County, PA, Columbia County, PA, Dauphin County, PA, Delaware County, PA, Lackawanna County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Luzerne County, PA, Lycoming County, PA, Monroe County, PA, Montgomery County, PA, Montour County, PA, Northampton County, PA, Northumberland County, PA, Philadelphia County, PA, Pike County, PA, Schuylkill County, PA, Snyder County, PA, Sullivan County, PA, Susquehanna County, PA, Tioga County, PA, Wayne County, PA, Wyoming County, PA, York County, PA

The radar

The Binghamton radar (KBGM), 129 km from the middle of the area, began a volume at 18:20 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, 6.3 hours before the alert went out and 186 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-pSkew-T log-p diagram, Phillips Aaf/Abe, MD at 12:00Z on 2011-05-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 143 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phillips Aaf/Abe, MD at 12:00Z on 2011-05-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -13 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
143 J/kg
Mixed-layer CIN
-55 J/kg
Mixed-layer LCL
819 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
-13 m²/s²
0-3 km storm-relative helicity
53 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.1

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.

IssuedProductOfficeCountiesLasted
May 19, 10:47 AM EDTMesoscale DiscussionSPCBergen, Essex, Hudson, Hunterdon, Mercer, Middlesex and 6 more88 min
May 19, 12:20 PM EDTSevere Thunderstorm WatchSPCBergen, Burlington, Camden, Essex, Gloucester, Hudson and 9 more8 hr
May 19, 5:02 PM EDTMesoscale DiscussionSPCBergen, Burlington, Camden, Essex, Gloucester, Hudson and 9 more58 min

Nearby

Mesoscale Discussions in Pennsylvania, 2011Mesoscale Discussions in New York, 2011Mesoscale Discussions in New Jersey, 2011Every 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; radar from the NEXRAD Level II archive.