Alert archive / Pennsylvania / Mesoscale Discussions in 2004
Mesoscale Discussion 2063
The Storm Prediction Center issued this mesoscale discussion at Aug 20, 2004, 7:15 PM EDT for Allegany County, Garrett County, Maryland; 5 counties in Pennsylvania; Mineral County, West Virginia. It was in force for 90 min.
The area
The outline as issued.
The facts
- Issued
- Aug 20, 2004, 7:15 PM EDT (23:15 UTC)
- Expired
- Aug 20, 2004, 8:45 PM EDT
- In force
- 90 min
- Issued by
- the Storm Prediction Center
Counties Allegany County, MD, Garrett County, MD, Cambria County, PA, Clearfield County, PA, Indiana County, PA, Somerset County, PA, Westmoreland County, PA, Mineral County, WV
The radar
The Pittsburgh radar (KPBZ), 106 km from the middle of the area, began a volume at 23:17 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, 11.3 hours before the alert went out and 91 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
- 181 J/kg
- Mixed-layer CIN
- -102 J/kg
- Mixed-layer LCL
- 860 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 19 m²/s²
- 0-3 km storm-relative helicity
- 71 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 |
|---|---|---|---|---|
| Aug 19, 8:28 PM EDT | Mesoscale Discussion | SPC | Anne Arundel, Baltimore, Carroll, Cecil, Frederick, Harford and 5 more | 92 min |
| Aug 20, 4:03 PM EDT | Mesoscale Discussion | SPC | Allegany, Baltimore, Carroll, Frederick, Garrett, Howard and 3 more | 2 hr |
| Aug 20, 4:25 PM EDT | Severe Thunderstorm Watch | SPC | Garrett | 5 hr |
| Aug 20, 11:56 AM EDT | Mesoscale Discussion | SPC | Bradford, Centre, Clinton, Columbia, Lackawanna, Luzerne and 10 more | 2 hr |
| Aug 20, 2:05 PM EDT | Severe Thunderstorm Watch | SPC | Blair, Bradford, Cambria, Cameron, Carbon, Centre and 27 more | 5 hr |
| Aug 20, 3:41 PM EDT | Mesoscale Discussion | SPC | Blair, Bradford, Cambria, Cameron, Carbon, Centre and 27 more | 2 hr |
| Aug 20, 6:10 PM EDT | Severe Thunderstorm Watch | SPC | Bradford, Cameron, Carbon, Centre, Clinton, Columbia and 21 more | 5 hr |
Nearby
Mesoscale Discussions in Pennsylvania, 2004Mesoscale Discussions in Maryland, 2004Mesoscale Discussions in West Virginia, 2004Every mesoscale discussion in 2004
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.