Alert archive / Pennsylvania / Mesoscale Discussions in 2020
Mesoscale Discussion 302
The Storm Prediction Center issued this mesoscale discussion at Apr 7, 2020, 10:54 PM EDT for 25 counties in Pennsylvania. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 7, 2020, 10:54 PM EDT (02:54 UTC)
- Expired
- Apr 8, 2020, 1:00 AM EDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
All 25 counties
Armstrong 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, Cumberland County, PA, Dauphin County, PA, Elk County, PA, Forest County, PA, Huntingdon County, PA, Indiana County, PA, Jefferson County, PA, Juniata County, PA, Mifflin County, PA, Montour County, PA, Northumberland County, PA, Perry County, PA, Snyder County, PA, Union County, PA, Venango County, PA, Warren County, PA
The radar
The State College radar (KCCX), 36 km from the middle of the area, began a volume at 02:56 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Pittsburgh, PA (KPIT), launched 00:00Z, 2.9 hours before the alert went out and 162 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
- 43 J/kg
- Mixed-layer CIN
- -141 J/kg
- Mixed-layer LCL
- 1005 m above ground
- 0-6 km bulk shear
- 59 kt
- 0-1 km storm-relative helicity
- 346 m²/s²
- 0-3 km storm-relative helicity
- 427 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 7, 9:07 PM EDT | Severe Thunderstorm Watch | SPC | Crawford, Erie | 6 hr |
| Apr 7, 10:04 PM EDT | Mesoscale Discussion | SPC | Beaver, Crawford, Lawrence, Mercer, Venango | 86 min |
| Apr 7, 11:40 PM EDT | Severe Thunderstorm Watch | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Fayette and 9 more | 6 hr |
| Apr 8, 1:52 AM EDT | Mesoscale Discussion | SPC | Bedford, Cambria, Fayette, Fulton, Greene, Somerset and 2 more | 83 min |
| Apr 8, 2:14 AM EDT | Severe Thunderstorm Watch | SPC | Bedford, Franklin, Fulton | 2 hr |
Nearby
Mesoscale Discussions in Pennsylvania, 2020Every mesoscale discussion in 2020
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.