Alert archive / Pennsylvania / Mesoscale Discussions in 2009
Mesoscale Discussion 863
The Storm Prediction Center issued this mesoscale discussion at May 24, 2009, 7:11 PM EDT for 12 counties in New Jersey; 4 counties in New York; 16 counties in Pennsylvania. It was in force for 64 min.
The area
The outline as issued.
The facts
- Issued
- May 24, 2009, 7:11 PM EDT (23:11 UTC)
- Expired
- May 24, 2009, 8:15 PM EDT
- In force
- 64 min
- Issued by
- the Storm Prediction Center
All 32 counties
Bergen County, NJ, Essex County, NJ, Hudson County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Passaic County, NJ, Somerset County, NJ, Union County, NJ, Warren County, NJ, Kings County, NY, New York County, NY, Queens County, NY, Richmond County, NY, Adams County, PA, Berks County, PA, Bucks County, PA, Chester County, PA, Cumberland County, PA, Dauphin County, PA, Delaware County, PA, Franklin County, PA, Fulton County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Montgomery County, PA, Northampton County, PA, Philadelphia County, PA, York County, PA
The radar
The Philadelphia radar (KDIX), 115 km from the middle of the area, began a volume at 23:14 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, 11.2 hours before the alert went out and 229 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
- 222 J/kg
- Mixed-layer CIN
- -104 J/kg
- Mixed-layer LCL
- 979 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 119 m²/s²
- 0-3 km storm-relative helicity
- 78 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 |
|---|---|---|---|---|
| May 24, 11:49 AM EDT | Mesoscale Discussion | SPC | Bergen, Essex, Hudson, Hunterdon, Morris, Passaic and 4 more | 116 min |
Nearby
Mesoscale Discussions in Pennsylvania, 2009Mesoscale Discussions in New Jersey, 2009Mesoscale Discussions in New York, 2009Every mesoscale discussion in 2009
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.