Alert archive / Pennsylvania / Mesoscale Discussions in 2011
Mesoscale Discussion 999
The Storm Prediction Center issued this mesoscale discussion at May 27, 2011, 6:14 PM EDT for 5 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- May 27, 2011, 6:14 PM EDT (22:14 UTC)
- Expired
- May 27, 2011, 8:15 PM EDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 88 counties
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, Washington County, MD, Broome County, NY, Chemung County, NY, Chenango County, NY, Cortland County, NY, Delaware County, NY, Fulton County, NY, Madison County, NY, Montgomery County, NY, Oneida County, NY, Otsego County, NY, Schenectady County, NY, Schoharie County, NY, Schuyler County, NY, Sullivan County, NY, Tioga County, NY, Tompkins County, NY, Adams County, PA, Bedford County, PA, Berks County, PA, Bradford County, PA, Carbon County, PA, Centre County, PA, Chester County, PA, Clinton County, PA, Columbia County, PA, Cumberland County, PA, Dauphin County, PA, Franklin County, PA, Fulton County, PA, Huntingdon County, PA, Juniata County, PA, Lackawanna County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Luzerne County, PA, Lycoming County, PA, Mifflin County, PA, Monroe County, PA, Montour County, PA, Northampton County, PA, Northumberland County, PA, Perry County, PA, Pike County, PA, Schuylkill County, PA, Snyder County, PA, Sullivan County, PA, Susquehanna County, PA, Tioga County, PA, Union County, PA, Wayne County, PA, Wyoming County, PA, York 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, Prince William County, VA, Rappahannock County, VA, Shenandoah County, VA, Stafford County, VA, Warren County, VA, Berkeley County, WV, Hampshire County, WV, Jefferson County, WV, Morgan County, WV
The radar
The Binghamton radar (KBGM), 136 km from the middle of the area, began a volume at 22:13 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, 10.2 hours before the alert went out and 171 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.
- Mixed-layer CAPE
- 95 J/kg
- Mixed-layer CIN
- -299 J/kg
- Mixed-layer LCL
- 1125 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km storm-relative helicity
- -15 m²/s²
- 0-3 km storm-relative helicity
- 20 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.2
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 27, 12:24 PM EDT | Mesoscale Discussion | SPC | Baltimore, Carroll, Frederick, Howard, Montgomery, Prince George's and 2 more | 96 min |
| May 27, 12:57 PM EDT | Severe Thunderstorm Watch | SPC | Allegany, Anne Arundel, Baltimore, Calvert, Carroll, Charles and 8 more | 9 hr |
| May 27, 3:29 PM EDT | Mesoscale Discussion | SPC | Saint Mary's | 91 min |
| May 27, 1:18 PM EDT | Mesoscale Discussion | SPC | Washington | 87 min |
| May 27, 2:00 PM EDT | Severe Thunderstorm Watch | SPC | Albany, Columbia, Essex, Fulton, Greene, Hamilton and 9 more | 6 hr |
| May 27, 5:49 PM EDT | Mesoscale Discussion | SPC | Albany, Columbia, Essex, Fulton, Greene, Hamilton and 8 more | 56 min |
| May 26, 8:54 PM EDT | Mesoscale Discussion | SPC | Adams, Berks, Bradford, Carbon, Columbia, Cumberland and 21 more | 66 min |
| May 26, 11:22 PM EDT | Mesoscale Discussion | SPC | Albemarle, Amherst, Appomattox, Augusta, Bedford, Buckingham and 18 more | 113 min |
| May 27, 11:26 AM EDT | Mesoscale Discussion | SPC | Brunswick, Dinwiddie, Greensville, Lunenburg, Mecklenburg, Nottoway and 1 more | 94 min |
| May 27, 12:06 PM EDT | Severe Thunderstorm Watch | SPC | Amelia, Amherst, Appomattox, Bedford, Botetourt, Brunswick and 52 more | 7 hr |
| May 27, 6:24 PM EDT | Mesoscale Discussion | SPC | Albemarle, Amelia, Amherst, Appomattox, Bedford, Brunswick and 43 more | 66 min |
Nearby
Mesoscale Discussions in Pennsylvania, 2011Mesoscale Discussions in Virginia, 2011Mesoscale Discussions in New York, 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.