Alert archive / Pennsylvania / Mesoscale Discussions in 2004
Mesoscale Discussion 1504
The Storm Prediction Center issued this mesoscale discussion at Jul 4, 2004, 4:55 PM EDT for Allegany County, Garrett County, Maryland; 15 counties in Pennsylvania; 10 counties in West Virginia. It was in force for 65 min.
The area
The outline as issued.
The facts
- Issued
- Jul 4, 2004, 4:55 PM EDT (20:55 UTC)
- Expired
- Jul 4, 2004, 6:00 PM EDT
- In force
- 65 min
- Issued by
- the Storm Prediction Center
All 27 counties
Allegany County, MD, Garrett County, MD, Bedford County, PA, Blair County, PA, Cambria County, PA, Cameron County, PA, Clearfield County, PA, Elk County, PA, Fayette County, PA, Fulton County, PA, Huntingdon County, PA, Indiana County, PA, Jefferson County, PA, McKean County, PA, Potter County, PA, Somerset County, PA, Westmoreland County, PA, Berkeley County, WV, Grant County, WV, Hampshire County, WV, Hardy County, WV, Mineral County, WV, Morgan County, WV, Pendleton County, WV, Preston County, WV, Randolph County, WV, Tucker County, WV
The radar
The State College radar (KCCX), 92 km from the middle of the area, began a volume at 20:55 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
Washington/Dulle, VA (KIAD), launched 12:00Z, 8.9 hours before the alert went out and 195 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
- 1158 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 547 m above ground
- 0-6 km bulk shear
- 21 kt
- 0-1 km storm-relative helicity
- 90 m²/s²
- 0-3 km storm-relative helicity
- 64 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.2
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 |
|---|---|---|---|---|
| Jul 4, 3:00 PM EDT | Mesoscale Discussion | SPC | Garrett | 2 hr |
| Jul 4, 11:08 AM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Cambria, Cameron and 17 more | 3 hr |
| Jul 4, 12:50 PM EDT | Severe Thunderstorm Watch | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Crawford and 10 more | 5 hr |
| Jul 4, 7:29 PM EDT | Mesoscale Discussion | SPC | Cameron, Centre, Clinton, Potter, Tioga | 61 min |
Nearby
Mesoscale Discussions in Pennsylvania, 2004Mesoscale Discussions in West Virginia, 2004Mesoscale Discussions in Maryland, 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.