Alert archive / Pennsylvania / Mesoscale Discussions in 2011
Mesoscale Discussion 115
The Storm Prediction Center issued this mesoscale discussion at Feb 20, 2011, 7:46 PM EST for 10 counties in New York; 30 counties in Pennsylvania. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Feb 20, 2011, 7:46 PM EST (00:46 UTC)
- Expired
- Feb 20, 2011, 11:45 PM EST
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
All 40 counties
Allegany County, NY, Cattaraugus County, NY, Chautauqua County, NY, Chemung County, NY, Erie County, NY, Livingston County, NY, Schuyler County, NY, Steuben County, NY, Wyoming County, NY, Yates County, NY, Armstrong County, PA, Blair County, PA, Bradford County, PA, Butler County, PA, Cameron County, PA, Centre County, PA, Clarion County, PA, Clearfield County, PA, Clinton County, PA, Crawford County, PA, Elk County, PA, Erie County, PA, Forest County, PA, Huntingdon County, PA, Indiana County, PA, Jefferson County, PA, Juniata County, PA, Lycoming County, PA, McKean County, PA, Mercer County, PA, Mifflin County, PA, Montour County, PA, Northumberland County, PA, Potter County, PA, Snyder County, PA, Sullivan County, PA, Tioga County, PA, Union County, PA, Venango County, PA, Warren County, PA
The radar
The State College radar (KCCX), 96 km from the middle of the area, began a volume at 00:47 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
Pittsburgh, PA (KPIT), launched 00:00Z, 0.8 hours before the alert went out and 208 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 455 m above ground
- 0-6 km bulk shear
- 73 kt
- 0-1 km storm-relative helicity
- 615 m²/s²
- 0-3 km storm-relative helicity
- 1010 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 |
|---|---|---|---|---|
| Feb 20, 11:50 PM EST | Mesoscale Discussion | SPC | Allegany, Broome, Cattaraugus, Chautauqua, Chemung, Chenango and 16 more | 5 hr |
| Feb 21, 5:58 PM EST | Mesoscale Discussion | SPC | Adams, Allegheny, Armstrong, Bedford, Blair, Cambria and 12 more | 4 hr |
| Feb 21, 6:33 PM EST | Mesoscale Discussion | SPC | Fayette, Greene | 5 hr |
Nearby
Mesoscale Discussions in Pennsylvania, 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.