Alert archive / Pennsylvania / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 791
The Storm Prediction Center issued this severe thunderstorm watch at Aug 19, 2011, 1:04 PM EDT for 5 states. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 19, 2011, 1:04 PM EDT (17:04 UTC)
- Expired
- Aug 19, 2011, 9:00 PM EDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 81 counties
Greater Bridgeport Planning Region, CT, Northwest Hills Planning Region, CT, Berkshire County, MA, Atlantic County, NJ, Bergen County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Essex County, NJ, Gloucester 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, Salem County, NJ, Somerset County, NJ, Sussex County, NJ, Union County, NJ, Warren County, NJ, Albany County, NY, Bronx County, NY, Broome County, NY, Chenango County, NY, Columbia County, NY, Delaware County, NY, Dutchess County, NY, Greene County, NY, Kings County, NY, Montgomery County, NY, New York County, NY, Orange County, NY, Otsego County, NY, Putnam County, NY, Queens County, NY, Rensselaer County, NY, Richmond County, NY, Rockland County, NY, Schenectady County, NY, Schoharie 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, Franklin County, PA, Fulton County, PA, Huntingdon County, PA, Juniata County, PA, Lackawanna County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Luzerne County, PA, Mifflin 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, Susquehanna County, PA, Union County, PA, Wayne County, PA, Wyoming County, PA, York County, PA
The radar
The Binghamton radar (KBGM), 92 km from the middle of the area, began a volume at 17:07 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 5%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 50%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 50%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
62 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 19, 1:10 PM EDT | Severe Thunderstorm Warning | BGM | Broome, Delaware | 50 min |
| Aug 19, 1:13 PM EDT | Severe Thunderstorm Warning | CTP | Centre, Huntingdon, Juniata, Mifflin, Snyder, Union | 47 min |
| Aug 19, 1:22 PM EDT | Severe Thunderstorm Warning | BGM | Susquehanna, Wyoming | 38 min |
| Aug 19, 1:36 PM EDT | Severe Thunderstorm Warning | ALY | Albany, Schenectady, Schoharie | 54 min |
| Aug 19, 1:43 PM EDT | Severe Thunderstorm Warning | ALY | Ulster | 62 min |
| Aug 19, 1:45 PM EDT | Severe Thunderstorm Warning | CTP | Snyder, Union | 60 min |
| Aug 19, 1:46 PM EDT | Severe Thunderstorm Warning | PHI | Monroe | 59 min |
| Aug 19, 1:54 PM EDT | Severe Thunderstorm Warning | CTP | Blair, Huntingdon | 66 min |
| Aug 19, 1:59 PM EDT | Severe Thunderstorm Warning | CTP | Lycoming, Union | 61 min |
| Aug 19, 2:13 PM EDT | Flash Flood Warning | BGM | Luzerne, Wyoming | 4 hr |
| Aug 19, 2:35 PM EDT | Severe Thunderstorm Warning | PHI | Carbon, Monroe | 70 min |
| Aug 19, 2:41 PM EDT | Severe Thunderstorm Warning | BGM | Luzerne | 49 min |
| Aug 19, 2:45 PM EDT | Flash Flood Warning | ALY | Ulster | 4 hr |
| Aug 19, 2:50 PM EDT | Severe Thunderstorm Warning | CTP | Dauphin, Lebanon, Schuylkill | 55 min |
| Aug 19, 2:52 PM EDT | Flash Flood Warning | BGM | Wayne | 3 hr |
| Aug 19, 2:57 PM EDT | Flash Flood Warning | PHI | Carbon, Monroe | 3 hr |
| Aug 19, 3:00 PM EDT | Severe Thunderstorm Warning | BGM | Sullivan | 20 min |
| Aug 19, 3:01 PM EDT | Flash Flood Warning | BGM | Luzerne | 3 hr |
| Aug 19, 3:05 PM EDT | Severe Thunderstorm Warning | ALY | Albany, Montgomery, Schenectady, Schoharie | 55 min |
| Aug 19, 3:15 PM EDT | Severe Thunderstorm Warning | ALY | Ulster | 60 min |
| Aug 19, 3:27 PM EDT | Severe Thunderstorm Warning | CTP | Schuylkill | 78 min |
| Aug 19, 3:29 PM EDT | Severe Thunderstorm Warning | CTP | Adams, Cumberland | 61 min |
| Aug 19, 3:44 PM EDT | Severe Thunderstorm Warning | ALY | Albany, Greene, Montgomery, Schenectady, Schoharie | 50 min |
| Aug 19, 3:47 PM EDT | Severe Thunderstorm Warning | PHI | Carbon, Monroe | 58 min |
| Aug 19, 3:52 PM EDT | Severe Thunderstorm Warning | CTP | Adams | 53 min |
| Aug 19, 4:01 PM EDT | Severe Thunderstorm Warning | ALY | Berkshire | 44 min |
| Aug 19, 4:03 PM EDT | Severe Thunderstorm Warning | OKX | Passaic | 42 min |
| Aug 19, 4:14 PM EDT | Severe Thunderstorm Warning | CTP | Lancaster, York | 61 min |
| Aug 19, 4:28 PM EDT | Flash Flood Warning | OKX | Orange | 2 hr |
| Aug 19, 4:29 PM EDT | Severe Thunderstorm Warning | PHI | Warren | 61 min |
| Aug 19, 4:38 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden | 67 min |
| Aug 19, 4:43 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Passaic | 62 min |
| Aug 19, 4:48 PM EDT | Severe Thunderstorm Warning | CTP | Lancaster, York | 72 min |
| Aug 19, 4:52 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Bucks, Lehigh, Montgomery, Northampton | 53 min |
| Aug 19, 5:05 PM EDT | Flash Flood Warning | OKX | Passaic | 55 min |
| Aug 19, 5:10 PM EDT | Severe Thunderstorm Warning | ALY | Dutchess, Ulster | 50 min |
| Aug 19, 5:12 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Morris, Sussex, Warren | 78 min |
| Aug 19, 5:17 PM EDT | Severe Thunderstorm Warning | OKX | Orange, Putnam | 43 min |
| Aug 19, 5:24 PM EDT | Severe Thunderstorm Warning | ALY | Berkshire | 66 min |
| Aug 19, 5:26 PM EDT | Severe Thunderstorm Warning | CTP | Lancaster | 34 min |
| Aug 19, 5:29 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Mercer, Middlesex, Monmouth, Ocean | 50 min |
| Aug 19, 5:35 PM EDT | Severe Thunderstorm Warning | PHI | Chester | 55 min |
| Aug 19, 5:42 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Passaic | 30 min |
| Aug 19, 5:42 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Montgomery | 48 min |
| Aug 19, 5:46 PM EDT | Severe Thunderstorm Warning | OKX | Greater Bridgeport Planning Region | 59 min |
| Aug 19, 5:59 PM EDT | Flash Flood Warning | OKX | Bergen, Passaic | 91 min |
| Aug 19, 5:59 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Mercer, Morris, Somerset | 80 min |
| Aug 19, 6:03 PM EDT | Severe Thunderstorm Warning | OKX | Putnam, Rockland, Westchester | 45 min |
| Aug 19, 6:14 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Gloucester, Mercer, Salem | 65 min |
| Aug 19, 6:18 PM EDT | Severe Thunderstorm Warning | ALY | Northwest Hills Planning Region | 41 min |
| Aug 19, 6:20 PM EDT | Severe Thunderstorm Warning | OKX | Bergen, Essex, Hudson, Passaic, Union | 40 min |
| Aug 19, 6:24 PM EDT | Severe Thunderstorm Warning | PHI | Morris | 28 min |
| Aug 19, 6:27 PM EDT | Flash Flood Warning | OKX | Putnam, Rockland, Westchester | 42 min |
| Aug 19, 6:29 PM EDT | Severe Thunderstorm Warning | OKX | Bergen | 46 min |
| Aug 19, 6:46 PM EDT | Flash Flood Warning | OKX | Bergen, Essex, Hudson, Passaic, Union | 59 min |
| Aug 19, 6:54 PM EDT | Severe Thunderstorm Warning | PHI | Middlesex, Monmouth | 31 min |
| Aug 19, 6:59 PM EDT | Severe Thunderstorm Warning | OKX | Hudson, Union | 46 min |
| Aug 19, 7:00 PM EDT | Severe Thunderstorm Warning | OKX | Bergen | 45 min |
| Aug 19, 7:16 PM EDT | Severe Thunderstorm Warning | OKX | Essex, Hudson | 44 min |
| Aug 19, 7:24 PM EDT | Flash Flood Warning | OKX | Bergen, Hudson | 66 min |
| Aug 19, 7:46 PM EDT | Severe Thunderstorm Warning | OKX | Nassau, Queens | 44 min |
| Aug 19, 8:29 PM EDT | Flash Flood Warning | OKX | Westchester | 59 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Albany, NY (KALY), launched 12:00Z, 5.1 hours before the alert went out and 186 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
- 205 J/kg
- Mixed-layer CIN
- -129 J/kg
- Mixed-layer LCL
- 940 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- -1 m²/s²
- 0-3 km storm-relative helicity
- 42 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 19, 12:43 PM EDT | Mesoscale Discussion | SPC | 62 min | |
| Aug 19, 6:42 PM EDT | Mesoscale Discussion | SPC | 63 min | |
| Aug 19, 7:44 PM EDT | Mesoscale Discussion | SPC | Atlantic, Burlington, Camden, Cumberland, Essex, Gloucester and 8 more | 61 min |
Nearby
Severe Thunderstorm Watches in Pennsylvania, 2011Severe Thunderstorm Watches in New York, 2011Severe Thunderstorm Watches in New Jersey, 2011Every severe thunderstorm watch in 2011
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.