Alert archive / Pennsylvania / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 397
The Storm Prediction Center issued this severe thunderstorm watch at May 29, 2011, 6:17 PM EDT for 11 counties in Ohio; 19 counties in Pennsylvania. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- May 29, 2011, 6:17 PM EDT (22:17 UTC)
- Expired
- May 29, 2011, 11:38 PM EDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 30 counties
Ashtabula County, OH, Cuyahoga County, OH, Erie County, OH, Geauga County, OH, Huron County, OH, Lake County, OH, Lorain County, OH, Medina County, OH, Portage County, OH, Summit County, OH, Trumbull County, OH, Armstrong County, PA, Butler County, PA, Cameron County, PA, Centre County, PA, Clarion County, PA, Clearfield County, PA, Clinton County, PA, Crawford County, PA, Elk County, PA, Erie County, PA, Forest County, PA, Jefferson County, PA, Lycoming County, PA, McKean County, PA, Mercer County, PA, Potter County, PA, Tioga County, PA, Venango County, PA, Warren County, PA
The radar
The Cleveland radar (KCLE), 90 km from the middle of the area, began a volume at 22:17 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.
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
- 60%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
8 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 29, 7:00 PM EDT | Severe Thunderstorm Warning | CLE | Erie, Lorain | 48 min |
| May 29, 7:10 PM EDT | Severe Thunderstorm Warning | CLE | Cuyahoga, Geauga, Lake | 65 min |
| May 29, 7:56 PM EDT | Severe Thunderstorm Warning | CLE | Ashtabula, Trumbull | 64 min |
| May 29, 8:12 PM EDT | Severe Thunderstorm Warning | CLE | Geauga, Portage, Trumbull | 63 min |
| May 29, 8:19 PM EDT | Severe Thunderstorm Warning | CTP | Warren | 56 min |
| May 29, 8:39 PM EDT | Severe Thunderstorm Warning | PBZ | Mercer | 51 min |
| May 29, 9:09 PM EDT | Severe Thunderstorm Warning | PBZ | Armstrong, Butler, Clarion, Forest, Mercer, Venango | 51 min |
| May 29, 9:21 PM EDT | Severe Thunderstorm Warning | CTP | McKean, Warren | 67 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
Pittsburgh, PA (KPIT), launched 12:00Z, 10.3 hours before the alert went out and 148 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1688 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 68 m²/s²
- 0-3 km storm-relative helicity
- 94 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 |
|---|---|---|---|---|
| May 29, 12:59 PM EDT | Mesoscale Discussion | SPC | Defiance, Fulton, Henry, Lucas, Ottawa, Paulding and 4 more | 61 min |
| May 29, 1:29 PM EDT | Tornado Watch | SPC | Allen, Defiance, Fulton, Hancock, Henry, Lucas and 8 more | 7 hr |
| May 29, 4:17 PM EDT | Mesoscale Discussion | SPC | Defiance, Fulton, Henry, Lucas, Ottawa, Paulding and 3 more | 88 min |
| May 29, 6:05 PM EDT | Mesoscale Discussion | SPC | Ashland, Ashtabula, Cuyahoga, Geauga, Lake, Lorain and 5 more | 25 min |
| May 29, 6:51 PM EDT | Mesoscale Discussion | SPC | Allen, Fulton, Hancock, Henry, Lucas, Ottawa and 4 more | 54 min |
| May 29, 7:28 PM EDT | Mesoscale Discussion | SPC | Ashtabula, Cuyahoga, Erie, Geauga, Huron, Lake and 5 more | 62 min |
Nearby
Severe Thunderstorm Watches in Pennsylvania, 2011Severe Thunderstorm Watches in Ohio, 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.