Alert archive / Pennsylvania / Mesoscale Discussions in 2012
Mesoscale Discussion 1919
The Storm Prediction Center issued this mesoscale discussion at Sep 7, 2012, 6:38 PM EDT for 4 states. It was in force for 97 min.
The area
The outline as issued.
The facts
- Issued
- Sep 7, 2012, 6:38 PM EDT (22:38 UTC)
- Expired
- Sep 7, 2012, 8:15 PM EDT
- In force
- 97 min
- Issued by
- the Storm Prediction Center
All 68 counties
Allegany County, NY, Cattaraugus County, NY, Chautauqua County, NY, Livingston County, NY, Steuben County, NY, Wyoming County, NY, Athens County, OH, Belmont County, OH, Carroll County, OH, Columbiana County, OH, Guernsey County, OH, Harrison County, OH, Hocking County, OH, Jackson County, OH, Jefferson County, OH, Mahoning County, OH, Meigs County, OH, Monroe County, OH, Morgan County, OH, Muskingum County, OH, Noble County, OH, Perry County, OH, Stark County, OH, Trumbull County, OH, Tuscarawas County, OH, Vinton County, OH, Washington County, OH, Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Bedford County, PA, Blair County, PA, Butler County, PA, Cambria County, PA, Cameron County, PA, Centre County, PA, Clarion County, PA, Clearfield County, PA, Clinton County, PA, Crawford County, PA, Elk County, PA, Fayette County, PA, Forest County, PA, Greene County, PA, Huntingdon County, PA, Indiana County, PA, Jefferson County, PA, Lawrence County, PA, McKean County, PA, Mercer County, PA, Potter County, PA, Somerset County, PA, Venango County, PA, Warren County, PA, Washington County, PA, Westmoreland County, PA, Brooke County, WV, Doddridge County, WV, Hancock County, WV, Marion County, WV, Marshall County, WV, Monongalia County, WV, Ohio County, WV, Pleasants County, WV, Ritchie County, WV, Tyler County, WV, Wetzel County, WV, Wood County, WV
The radar
The Pittsburgh radar (KPBZ), 21 km from the middle of the area, began a volume at 22:40 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
Pittsburgh, PA (KPIT), launched 12:00Z, 10.6 hours before the alert went out and 33 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
- 1010 J/kg
- Mixed-layer CIN
- -40 J/kg
- Mixed-layer LCL
- 1160 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 28 m²/s²
- 0-3 km storm-relative helicity
- 41 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 3.3
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 |
|---|---|---|---|---|
| Sep 7, 2:16 PM EDT | Mesoscale Discussion | SPC | Cattaraugus, Chautauqua | 59 min |
| Sep 7, 11:09 AM EDT | Mesoscale Discussion | SPC | Allen, Auglaize, Darke, Defiance, Mercer, Miami and 6 more | 2 hr |
| Sep 7, 11:36 AM EDT | Severe Thunderstorm Watch | SPC | Allen, Auglaize, Butler, Champaign, Clark, Crawford and 27 more | 6 hr |
| Sep 7, 1:16 PM EDT | Mesoscale Discussion | SPC | Allen, Auglaize, Champaign, Clark, Crawford, Darke and 21 more | 59 min |
| Sep 7, 3:22 PM EDT | Severe Thunderstorm Watch | SPC | Ashland, Ashtabula, Carroll, Columbiana, Coshocton, Crawford and 18 more | 4 hr |
| Sep 7, 3:39 PM EDT | Mesoscale Discussion | SPC | Butler, Champaign, Clark, Clermont, Clinton, Delaware and 16 more | 66 min |
| Sep 7, 4:22 PM EDT | Mesoscale Discussion | SPC | Butler, Clermont, Hamilton, Preble, Warren | 53 min |
| Sep 7, 4:41 PM EDT | Severe Thunderstorm Watch | SPC | Brown, Butler, Clark, Clermont, Clinton, Fairfield and 13 more | 6 hr |
Nearby
Mesoscale Discussions in Pennsylvania, 2012Mesoscale Discussions in Ohio, 2012Mesoscale Discussions in West Virginia, 2012Every mesoscale discussion in 2012
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.