Alert archive / Ohio / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 449

June 9, 201120 counties in New York; 34 counties in Ohio; 19 counties in Pennsylvania

The Storm Prediction Center issued this severe thunderstorm watch at Jun 9, 2011, 3:56 AM EDT for 20 counties in New York; 34 counties in Ohio; 19 counties in Pennsylvania. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jun 9, 2011, 3:56 AM EDT (07:56 UTC)
Expired
Jun 9, 2011, 9:37 AM EDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 73 counties

Allegany County, NY, Cattaraugus County, NY, Cayuga County, NY, Chautauqua County, NY, Chemung County, NY, Erie County, NY, Genesee County, NY, Livingston County, NY, Monroe County, NY, Niagara County, NY, Ontario County, NY, Orleans County, NY, Schuyler County, NY, Seneca County, NY, Steuben County, NY, Tioga County, NY, Tompkins County, NY, Wayne County, NY, Wyoming County, NY, Yates County, NY, Ashland County, OH, Ashtabula County, OH, Carroll County, OH, Columbiana County, OH, Coshocton County, OH, Crawford County, OH, Cuyahoga County, OH, Erie County, OH, Geauga County, OH, Hancock County, OH, Harrison County, OH, Holmes County, OH, Huron County, OH, Jefferson County, OH, Knox County, OH, Lake County, OH, Lorain County, OH, Lucas County, OH, Mahoning County, OH, Marion County, OH, Medina County, OH, Morrow County, OH, Ottawa County, OH, Portage County, OH, Richland County, OH, Sandusky County, OH, Seneca County, OH, Stark County, OH, Summit County, OH, Trumbull County, OH, Tuscarawas County, OH, Wayne County, OH, Wood County, OH, Wyandot County, OH, Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Butler County, PA, Cameron County, PA, Clarion County, PA, Crawford County, PA, Elk County, PA, Erie County, PA, Forest County, PA, Jefferson County, PA, Lawrence County, PA, McKean County, PA, Mercer County, PA, Potter County, PA, Tioga County, PA, Venango County, PA, Warren County, PA, Washington County, PA

The radar

The Cleveland radar (KCLE), 102 km from the middle of the area, began a volume at 07:58 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
60%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
50%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

6 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jun 9, 4:16 AM EDTSevere Thunderstorm WarningCLEOttawa29 min
Jun 9, 4:48 AM EDTSevere Thunderstorm WarningCLEHancock, Wyandot72 min
Jun 9, 5:39 AM EDTSevere Thunderstorm WarningCLECrawford, Marion, Morrow45 min
Jun 9, 6:10 AM EDTSevere Thunderstorm WarningCLEAshland, Holmes, Richland, Wayne65 min
Jun 9, 7:16 AM EDTSevere Thunderstorm WarningCLEHolmes, Stark, Wayne59 min
Jun 9, 7:41 AM EDTSevere Thunderstorm WarningPBZCarroll, Tuscarawas26 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 00:00Z, 7.9 hours before the alert went out and 166 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.

Skew-T log-pSkew-T log-p diagram, Pittsburgh, PA at 00:00Z on 2011-06-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3384 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Pittsburgh, PA at 00:00Z on 2011-06-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 72 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
3384 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
1289 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
72 m²/s²
0-3 km storm-relative helicity
78 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.9

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 8, 8:36 PM EDTMesoscale DiscussionSPCCayuga, Fulton, Hamilton, Herkimer, Jefferson, Lewis and 6 more84 min
Jun 8, 8:57 PM EDTSevere Thunderstorm WatchSPCCayuga, Fulton, Hamilton, Herkimer, Jefferson, Lewis and 9 more3 hr
Jun 9, 3:29 AM EDTMesoscale DiscussionSPCAllegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston and 10 more2 hr
Jun 9, 8:13 AM EDTMesoscale DiscussionSPCAllegany, Cattaraugus, Cayuga, Chautauqua, Chemung, Erie and 12 more2 hr
Jun 9, 10:36 AM EDTMesoscale DiscussionSPCAlbany, Allegany, Broome, Cattaraugus, Cayuga, Chemung and 30 more84 min
Jun 9, 11:33 AM EDTMesoscale DiscussionSPCAlbany, Broome, Chemung, Chenango, Columbia, Cortland and 16 more57 min
Jun 9, 12:06 PM EDTSevere Thunderstorm WatchSPCAlbany, Broome, Cayuga, Chemung, Chenango, Clinton and 28 more8 hr
Jun 9, 1:45 PM EDTMesoscale DiscussionSPCBronx, Dutchess, Kings, Nassau, New York, Orange and 6 more90 min
Jun 9, 2:34 PM EDTSevere Thunderstorm WatchSPCBronx, Kings, Nassau, New York, Orange, Putnam and 5 more7 hr
Jun 9, 3:18 PM EDTMesoscale DiscussionSPCAlbany, Broome, Chenango, Columbia, Cortland, Delaware and 20 more87 min
Jun 9, 4:17 PM EDTMesoscale DiscussionSPCBronx, Dutchess, Kings, Nassau, New York, Orange and 5 more88 min
Jun 9, 7:17 PM EDTMesoscale DiscussionSPCAlbany, Bronx, Columbia, Dutchess, Fulton, Greene and 19 more58 min
Jun 9, 12:53 PM EDTSevere Thunderstorm WatchSPCAthens, Belmont, Carroll, Columbiana, Coshocton, Gallia and 14 more7 hr
Jun 9, 6:31 PM EDTMesoscale DiscussionSPCButler, Clermont, Hamilton89 min
Jun 9, 6:17 PM EDTMesoscale DiscussionSPCAdams, Bedford, Blair, Cambria, Cumberland, Fayette and 8 more58 min

Nearby

Severe Thunderstorm Watches in Ohio, 2011Severe Thunderstorm Watches in New York, 2011Severe Thunderstorm Watches in Pennsylvania, 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.