Alert archive / Pennsylvania / Mesoscale Discussions in 2018
Mesoscale Discussion 1307
The Storm Prediction Center issued this mesoscale discussion at Aug 17, 2018, 2:42 PM EDT for 5 states. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 17, 2018, 2:42 PM EDT (18:42 UTC)
- Expired
- Aug 17, 2018, 5:15 PM EDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 60%
All 49 counties
Berkshire County, MA, Franklin County, MA, Hampden County, MA, Hampshire County, MA, Passaic County, NJ, Sussex County, NJ, Warren County, NJ, Albany County, NY, Broome County, NY, Chenango County, NY, Columbia County, NY, Delaware County, NY, Dutchess County, NY, Fulton County, NY, Greene County, NY, Montgomery County, NY, Orange County, NY, Otsego County, NY, Putnam County, NY, Rensselaer County, NY, Rockland County, NY, Saratoga County, NY, Schenectady County, NY, Schoharie County, NY, Sullivan County, NY, Tioga County, NY, Ulster County, NY, Bradford County, PA, Carbon County, PA, Columbia County, PA, Dauphin County, PA, Juniata County, PA, Lackawanna County, PA, Lehigh County, PA, Luzerne County, PA, Lycoming County, PA, Monroe County, PA, Montour County, PA, Northampton County, PA, Northumberland County, PA, Pike County, PA, Schuylkill County, PA, Snyder County, PA, Sullivan County, PA, Susquehanna County, PA, Union County, PA, Wayne County, PA, Wyoming County, PA, Bennington County, VT
The radar
The Albany radar (KENX), 102 km from the middle of the area, began a volume at 18:41 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
Albany, NY (KALY), launched 12:00Z, 6.7 hours before the alert went out and 121 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
- 106 J/kg
- Mixed-layer CIN
- -150 J/kg
- Mixed-layer LCL
- 1004 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 59 m²/s²
- 0-3 km storm-relative helicity
- 71 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 17, 3:44 PM EDT | Severe Thunderstorm Watch | SPC | Greater Bridgeport Planning Region, Capitol Planning Region, Northwest Hills Planning Region, Lower Connecticut River Valley Planning Region, Naugatuck Valley Planning Region | 7 hr |
| Aug 17, 7:31 PM EDT | Mesoscale Discussion | SPC | Bergen, Essex, Hudson, Hunterdon, Mercer, Middlesex and 7 more | 89 min |
Nearby
Mesoscale Discussions in Pennsylvania, 2018Mesoscale Discussions in New York, 2018Mesoscale Discussions in Massachusetts, 2018Every mesoscale discussion in 2018
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.