Alert archive / Pennsylvania / Mesoscale Discussions in 2009
Mesoscale Discussion 1680
The Storm Prediction Center issued this mesoscale discussion at Jul 26, 2009, 3:14 PM EDT for 5 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 26, 2009, 3:14 PM EDT (19:14 UTC)
- Expired
- Jul 26, 2009, 5:15 PM EDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 71 counties
Bristol County, MA, Hampden County, MA, Hampshire County, MA, Middlesex County, MA, Norfolk County, MA, Plymouth County, MA, Suffolk County, MA, Worcester County, MA, Bergen County, NJ, Burlington County, NJ, Camden County, NJ, Essex County, NJ, Hudson County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Ocean County, NJ, Passaic County, NJ, Somerset County, NJ, Sussex County, NJ, Union County, NJ, Warren County, NJ, Bronx County, NY, Dutchess County, NY, Kings County, NY, Nassau County, NY, New York County, NY, Orange County, NY, Putnam County, NY, Queens County, NY, Richmond County, NY, Rockland County, NY, Suffolk County, NY, Sullivan County, NY, Ulster County, NY, Westchester 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, Lackawanna County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Luzerne County, PA, Monroe County, PA, Montgomery County, PA, Montour County, PA, Northampton County, PA, Northumberland County, PA, Perry County, PA, Philadelphia County, PA, Pike County, PA, Schuylkill County, PA, Snyder County, PA, Union County, PA, Wayne County, PA, Wyoming County, PA, York County, PA, Bristol County, RI, Kent County, RI, Newport County, RI, Providence County, RI, Washington County, RI
The radar
The Philadelphia radar (KDIX), 97 km from the middle of the area, began a volume at 19:17 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
Brookhaven, NY (KOKX), launched 12:00Z, 7.2 hours before the alert went out and 142 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
- 933 J/kg
- Mixed-layer CIN
- -99 J/kg
- Mixed-layer LCL
- 889 m above ground
- 0-6 km bulk shear
- 40 kt
- 0-1 km storm-relative helicity
- 161 m²/s²
- 0-3 km storm-relative helicity
- 217 m²/s²
- Significant tornado parameter
- 0.5
- Supercell composite
- 3.3
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 |
|---|---|---|---|---|
| Jul 26, 1:13 PM EDT | Mesoscale Discussion | SPC | 2 hr | |
| Jul 26, 3:51 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, Southeastern Connecticut Planning Region and 1 more | 7 hr |
| Jul 26, 6:37 PM EDT | Mesoscale Discussion | SPC | 113 min | |
| Jul 26, 1:40 PM EDT | Mesoscale Discussion | SPC | Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 2 more | 2 hr |
| Jul 26, 2:07 PM EDT | Severe Thunderstorm Watch | SPC | Atlantic, Cape May, Cumberland, Gloucester, Salem | 7 hr |
| Jul 26, 4:16 PM EDT | Mesoscale Discussion | SPC | Atlantic, Cape May, Cumberland, Salem | 89 min |
| Jul 26, 12:56 PM EDT | Mesoscale Discussion | SPC | Allegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston and 6 more | 2 hr |
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.