Alert archive / Pennsylvania / Mesoscale Discussions in 2017
Mesoscale Discussion 1552
The Storm Prediction Center issued this mesoscale discussion at Aug 22, 2017, 3:08 PM EDT for 4 states. It was in force for 67 min.
The area
The outline as issued.
The facts
- Issued
- Aug 22, 2017, 3:08 PM EDT (19:08 UTC)
- Expired
- Aug 22, 2017, 4:15 PM EDT
- In force
- 67 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 95%
All 40 counties
Carroll County, MD, Bergen County, NJ, Essex County, NJ, Hunterdon County, NJ, Morris County, NJ, Passaic County, NJ, Somerset County, NJ, Sussex County, NJ, Warren County, NJ, Delaware County, NY, Dutchess County, NY, Orange County, NY, Putnam County, NY, Rockland County, NY, Sullivan County, NY, Ulster County, NY, Adams County, PA, Berks County, PA, Bucks County, PA, Carbon County, PA, Chester County, PA, Columbia County, PA, Cumberland County, PA, Dauphin County, PA, Delaware County, PA, Franklin County, PA, Lackawanna County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Luzerne County, PA, Monroe County, PA, Montgomery County, PA, Northampton County, PA, Northumberland County, PA, Perry County, PA, Pike County, PA, Schuylkill County, PA, Wayne County, PA, York County, PA
The radar
The Philadelphia radar (KDIX), 145 km from the middle of the area, began a volume at 19:09 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
Washington/Dulle, VA (KIAD), launched 12:00Z, 7.1 hours before the alert went out and 235 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
- 306 J/kg
- Mixed-layer CIN
- -96 J/kg
- Mixed-layer LCL
- 1320 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 58 m²/s²
- 0-3 km storm-relative helicity
- 75 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
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 |
|---|---|---|---|---|
| Aug 22, 12:39 PM EDT | Severe Thunderstorm Watch | SPC | Garrett | 8 hr |
| Aug 22, 4:19 PM EDT | Severe Thunderstorm Watch | SPC | Cecil | 8 hr |
| Aug 22, 7:07 PM EDT | Mesoscale Discussion | SPC | Bergen, Essex, Hudson, Hunterdon, Mercer, Middlesex and 6 more | 113 min |
| Aug 22, 11:55 AM EDT | Mesoscale Discussion | SPC | Allegany, Broome, Cattaraugus, Cayuga, Chemung, Chenango and 23 more | 3 hr |
| Aug 22, 12:23 PM EDT | Tornado Watch | SPC | Allegany, Broome, Cattaraugus, Cayuga, Chautauqua, Chemung and 36 more | 9 hr |
| Aug 22, 2:44 PM EDT | Mesoscale Discussion | SPC | Allegany, Broome, Cayuga, Chemung, Chenango, Clinton and 22 more | 2 hr |
| Aug 22, 3:55 PM EDT | Severe Thunderstorm Watch | SPC | Albany, Columbia, Dutchess, Greene, Rensselaer, Saratoga and 4 more | 8 hr |
| Aug 22, 4:48 PM EDT | Mesoscale Discussion | SPC | Broome, Cayuga, Chemung, Chenango, Clinton, Cortland and 21 more | 87 min |
| Aug 22, 5:49 PM EDT | Mesoscale Discussion | SPC | Albany, Columbia, Greene, Rensselaer, Washington | 116 min |
| Aug 22, 11:54 AM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Clarion, Greene and 5 more | 66 min |
| Aug 22, 2:44 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Blair, Butler, Cambria and 13 more | 91 min |
| Aug 22, 4:39 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Blair, Butler, Cambria and 13 more | 66 min |
Nearby
Mesoscale Discussions in Pennsylvania, 2017Mesoscale Discussions in New Jersey, 2017Mesoscale Discussions in New York, 2017Every mesoscale discussion in 2017
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.