Alert archive / Pennsylvania / Mesoscale Discussions in 2017
Mesoscale Discussion 1524
The Storm Prediction Center issued this mesoscale discussion at Aug 18, 2017, 4:34 PM EDT for 6 states. It was in force for 86 min.
The area
The outline as issued.
The facts
- Issued
- Aug 18, 2017, 4:34 PM EDT (20:34 UTC)
- Expired
- Aug 18, 2017, 6:00 PM EDT
- In force
- 86 min
- Issued by
- the Storm Prediction Center
All 73 counties
Kent County, DE, New Castle County, DE, Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Caroline County, MD, Carroll County, MD, Cecil County, MD, Charles County, MD, City of Baltimore, MD, Frederick County, MD, Harford County, MD, Howard County, MD, Kent County, MD, Montgomery County, MD, Prince George's County, MD, Queen Anne's County, MD, Talbot County, MD, Bergen County, NJ, Camden County, NJ, Essex County, NJ, Gloucester County, NJ, Hudson County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Morris County, NJ, Passaic County, NJ, Salem County, NJ, Somerset County, NJ, Sussex County, NJ, Union County, NJ, Warren County, NJ, Columbia County, NY, Delaware County, NY, Dutchess County, NY, Orange County, NY, Putnam County, NY, Rockland County, NY, Sullivan County, NY, Ulster County, NY, Westchester County, NY, Berks County, PA, Bucks County, PA, Carbon County, PA, Chester County, PA, Delaware 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, Philadelphia County, PA, Pike County, PA, Schuylkill County, PA, Wayne County, PA, York County, PA, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Manassas, VA, City of Manassas Park, VA, Culpeper County, VA, Fairfax County, VA, Fauquier County, VA, Loudoun County, VA, Madison County, VA, Prince William County, VA, Stafford County, VA
The radar
The Dover AFB radar (KDOX), 134 km from the middle of the area, began a volume at 20:36 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, 8.6 hours before the alert went out and 150 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
- 746 J/kg
- Mixed-layer CIN
- -72 J/kg
- Mixed-layer LCL
- 651 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 12 m²/s²
- 0-3 km storm-relative helicity
- 76 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
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 18, 2:27 PM EDT | Severe Thunderstorm Watch | SPC | Greater Bridgeport Planning Region, Northwest Hills Planning Region | 9 hr |
| Aug 18, 1:54 PM EDT | Mesoscale Discussion | SPC | Kent, New Castle | 2 hr |
| Aug 17, 8:00 PM EDT | Mesoscale Discussion | SPC | Crawford, Lawrence, Mercer, Venango | 90 min |
Nearby
Mesoscale Discussions in Pennsylvania, 2017Mesoscale Discussions in Maryland, 2017Mesoscale Discussions in New Jersey, 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.