Alert archive / Pennsylvania / Severe Thunderstorm Watches in 2013
Severe Thunderstorm Watch 520
The Storm Prediction Center issued this severe thunderstorm watch at Sep 11, 2013, 12:33 PM EDT for 4 states. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Sep 11, 2013, 12:33 PM EDT (16:33 UTC)
- Expired
- Sep 11, 2013, 9:00 PM EDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 106 counties
Allegany County, NY, Broome County, NY, Cattaraugus County, NY, Cayuga County, NY, Chautauqua County, NY, Chemung County, NY, Chenango County, NY, Cortland County, NY, Delaware County, NY, Jefferson County, NY, Lewis County, NY, Livingston County, NY, Madison County, NY, Monroe County, NY, Oneida County, NY, Onondaga County, NY, Ontario County, NY, Oswego County, NY, Otsego County, NY, Schuyler County, NY, Seneca County, NY, Steuben County, NY, Sullivan County, NY, Tioga County, NY, Tompkins County, NY, Wayne County, NY, Wyoming County, NY, Yates County, NY, Ashland County, OH, Ashtabula County, OH, Belmont County, OH, Carroll County, OH, Columbiana County, OH, Coshocton County, OH, Crawford County, OH, Geauga County, OH, Guernsey County, OH, Harrison County, OH, Holmes County, OH, Jefferson County, OH, Knox County, OH, Lake County, OH, Mahoning County, OH, Marion County, OH, Medina County, OH, Monroe County, OH, Morrow County, OH, Muskingum County, OH, Noble County, OH, Portage County, OH, Richland County, OH, Stark County, OH, Summit County, OH, Trumbull County, OH, Tuscarawas County, OH, Wayne County, OH, Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Bedford County, PA, Blair County, PA, Bradford County, PA, Butler County, PA, Cambria County, PA, Cameron County, PA, Centre County, PA, Clarion County, PA, Clearfield County, PA, Clinton County, PA, Columbia County, PA, Crawford County, PA, Elk County, PA, Erie County, PA, Fayette County, PA, Forest County, PA, Greene County, PA, Huntingdon County, PA, Indiana County, PA, Jefferson County, PA, Lackawanna County, PA, Lawrence County, PA, Luzerne County, PA, Lycoming County, PA, McKean County, PA, Mercer County, PA, Mifflin County, PA, Montour County, PA, Northumberland County, PA, Pike County, PA, Potter County, PA, Snyder County, PA, Somerset County, PA, Sullivan County, PA, Susquehanna County, PA, Tioga County, PA, Union County, PA, Venango County, PA, Warren County, PA, Washington County, PA, Wayne County, PA, Westmoreland County, PA, Wyoming County, PA, Brooke County, WV, Hancock County, WV, Marshall County, WV, Ohio County, WV
The radar
The State College radar (KCCX), 127 km from the middle of the area, began a volume at 16:33 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
- 10%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 70%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 20%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
33 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 11, 2:05 PM EDT | Severe Thunderstorm Warning | BGM | Susquehanna | 40 min |
| Sep 11, 2:06 PM EDT | Severe Thunderstorm Warning | CTP | Centre, Clinton, Lycoming | 54 min |
| Sep 11, 2:36 PM EDT | Severe Thunderstorm Warning | BUF | Allegany, Cattaraugus, Erie, Wyoming | 39 min |
| Sep 11, 3:10 PM EDT | Severe Thunderstorm Warning | BGM | Broome, Cortland, Tioga | 50 min |
| Sep 11, 3:26 PM EDT | Severe Thunderstorm Warning | BGM | Chemung, Schuyler, Tioga, Tompkins | 49 min |
| Sep 11, 3:30 PM EDT | Severe Thunderstorm Warning | BGM | Broome, Chenango, Delaware, Otsego | 45 min |
| Sep 11, 3:31 PM EDT | Severe Thunderstorm Warning | PBZ | Allegheny, Westmoreland | 44 min |
| Sep 11, 3:41 PM EDT | Severe Thunderstorm Warning | BUF | Oswego | 49 min |
| Sep 11, 3:41 PM EDT | Flash Flood Warning | PBZ | Allegheny, Westmoreland | 3 hr |
| Sep 11, 3:58 PM EDT | Severe Thunderstorm Warning | BGM | Broome, Chenango, Cortland, Tioga | 62 min |
| Sep 11, 3:58 PM EDT | Severe Thunderstorm Warning | CTP | Clinton, Potter, Tioga | 62 min |
| Sep 11, 4:06 PM EDT | Severe Thunderstorm Warning | CTP | Columbia, Lycoming, Montour, Northumberland, Sullivan, Union | 54 min |
| Sep 11, 4:15 PM EDT | Severe Thunderstorm Warning | BGM | Otsego | 60 min |
| Sep 11, 4:16 PM EDT | Flash Flood Warning | BGM | Broome, Chenango, Cortland, Tioga | 6 hr |
| Sep 11, 4:19 PM EDT | Severe Thunderstorm Warning | BGM | Lackawanna, Wayne | 56 min |
| Sep 11, 4:25 PM EDT | Flash Flood Warning | PBZ | Westmoreland | 2 hr |
| Sep 11, 4:38 PM EDT | Severe Thunderstorm Warning | BGM | Broome | 67 min |
| Sep 11, 4:42 PM EDT | Severe Thunderstorm Warning | CTP | Cambria | 63 min |
| Sep 11, 4:47 PM EDT | Flash Flood Warning | CTP | Potter | 3 hr |
| Sep 11, 4:58 PM EDT | Severe Thunderstorm Warning | BGM | Madison, Oneida, Onondaga | 62 min |
| Sep 11, 5:20 PM EDT | Flash Flood Warning | BGM | Broome, Tioga | 6 hr |
| Sep 11, 5:24 PM EDT | Flash Flood Warning | BGM | Lackawanna, Luzerne, Susquehanna, Wayne, Wyoming | 6 hr |
| Sep 11, 5:47 PM EDT | Severe Thunderstorm Warning | BUF | Oswego | 28 min |
| Sep 11, 5:47 PM EDT | Severe Thunderstorm Warning | CTP | Columbia, Dauphin, Montour, Northumberland, Schuylkill | 58 min |
| Sep 11, 6:32 PM EDT | Severe Thunderstorm Warning | CTP | Columbia, Dauphin, Montour, Northumberland, Schuylkill, Snyder | 58 min |
| Sep 11, 6:33 PM EDT | Severe Thunderstorm Warning | CTP | McKean, Potter | 57 min |
| Sep 11, 6:38 PM EDT | Severe Thunderstorm Warning | BUF | Allegany, Cattaraugus | 52 min |
| Sep 11, 6:43 PM EDT | Severe Thunderstorm Warning | PBZ | Ohio | 32 min |
| Sep 11, 6:58 PM EDT | Severe Thunderstorm Warning | BUF | Allegany, Livingston | 32 min |
| Sep 11, 7:01 PM EDT | Flash Flood Warning | CTP | McKean, Potter | 3 hr |
| Sep 11, 7:37 PM EDT | Flash Flood Warning | BUF | Allegany, Cattaraugus | 3 hr |
| Sep 11, 7:37 PM EDT | Severe Thunderstorm Warning | CTP | Columbia, Schuylkill | 53 min |
| Sep 11, 7:50 PM EDT | Severe Thunderstorm Warning | CTP | McKean, Potter | 55 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
Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 4.6 hours before the alert went out and 149 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
- 989 J/kg
- Mixed-layer CIN
- -133 J/kg
- Mixed-layer LCL
- 1346 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 100 m²/s²
- 0-3 km storm-relative helicity
- 141 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 0.8
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 11, 11:42 AM EDT | Mesoscale Discussion | SPC | Allegany, Broome, Cattaraugus, Cayuga, Chautauqua, Chemung and 20 more | 63 min |
| Sep 11, 1:30 PM EDT | Mesoscale Discussion | SPC | Albany, Clinton, Columbia, Essex, Franklin, Fulton and 8 more | 60 min |
| Sep 11, 2:33 PM EDT | Severe Thunderstorm Watch | SPC | Albany, Clinton, Columbia, Essex, Franklin, Fulton and 12 more | 9 hr |
| Sep 11, 2:47 PM EDT | Mesoscale Discussion | SPC | Allegany, Broome, Cattaraugus, Cayuga, Chautauqua, Chemung and 16 more | 58 min |
| Sep 11, 6:54 PM EDT | Mesoscale Discussion | SPC | Albany, Clinton, Columbia, Essex, Franklin, Fulton and 12 more | 96 min |
| Sep 11, 4:21 PM EDT | Mesoscale Discussion | SPC | Fulton, Lucas, Williams | 114 min |
| Sep 11, 4:39 PM EDT | Severe Thunderstorm Watch | SPC | Fulton, Williams | 4 hr |
Nearby
Severe Thunderstorm Watches in Pennsylvania, 2013Severe Thunderstorm Watches in New York, 2013Severe Thunderstorm Watches in Ohio, 2013Every severe thunderstorm watch in 2013
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.