Alert archive / Indiana / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 264

May 7, 201124 counties in Illinois; 42 counties in Indiana

The Storm Prediction Center issued this severe thunderstorm watch at May 7, 2011, 2:59 PM CDT for 24 counties in Illinois; 42 counties in Indiana. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
May 7, 2011, 2:59 PM CDT (19:59 UTC)
Expired
May 7, 2011, 10:00 PM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2.5 in
Strongest gust expected
60 kt
All 66 counties

Champaign County, IL, Clark County, IL, Coles County, IL, DeWitt County, IL, Douglas County, IL, Edgar County, IL, Ford County, IL, Grundy County, IL, Iroquois County, IL, Kankakee County, IL, Kendall County, IL, LaSalle County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, McLean County, IL, Moultrie County, IL, Peoria County, IL, Piatt County, IL, Tazewell County, IL, Vermilion County, IL, Will County, IL, Woodford County, IL, Bartholomew County, IN, Benton County, IN, Boone County, IN, Brown County, IN, Carroll County, IN, Cass County, IN, Clay County, IN, Clinton County, IN, Daviess County, IN, Fountain County, IN, Fulton County, IN, Grant County, IN, Greene County, IN, Hamilton County, IN, Hancock County, IN, Hendricks County, IN, Howard County, IN, Jasper County, IN, Johnson County, IN, Knox County, IN, Lawrence County, IN, Madison County, IN, Marion County, IN, Martin County, IN, Miami County, IN, Monroe County, IN, Montgomery County, IN, Morgan County, IN, Newton County, IN, Owen County, IN, Parke County, IN, Pulaski County, IN, Putnam County, IN, Shelby County, IN, Sullivan County, IN, Tippecanoe County, IN, Tipton County, IN, Vermillion County, IN, Vigo County, IN, Wabash County, IN, Warren County, IN, White County, IN

The radar

The Chicago radar (KLOT), 118 km from the middle of the area, began a volume at 19:58 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
20%
One or more EF2 to EF5 tornadoes
5%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
May 7, 3:28 PM CDTSevere Thunderstorm WarningLOTFord, Iroquois, Livingston32 min
May 7, 3:49 PM CDTSevere Thunderstorm WarningLOTFord, Iroquois41 min
May 7, 4:06 PM CDTTornado WarningILXChampaign, Vermilion39 min
May 7, 4:06 PM CDTTornado WarningLOTFord, Iroquois39 min
May 7, 4:32 PM CDTSevere Thunderstorm WarningLOTIroquois58 min
May 7, 4:44 PM CDTTornado WarningILXVermilion46 min
May 7, 4:59 PM CDTSevere Thunderstorm WarningILXChampaign, Vermilion46 min
May 7, 5:12 PM CDTTornado WarningILXChampaign31 min
May 7, 5:19 PM CDTSevere Thunderstorm WarningINDFountain, Vermillion, Warren41 min
May 7, 5:25 PM CDTSevere Thunderstorm WarningILXVermilion50 min
May 7, 5:26 PM CDTSevere Thunderstorm WarningLOTJasper, Newton45 min
May 7, 5:33 PM CDTSevere Thunderstorm WarningLOTKankakee33 min
May 7, 5:39 PM CDTSevere Thunderstorm WarningILXChampaign, Vermilion51 min
May 7, 5:58 PM CDTSevere Thunderstorm WarningINDFountain, Parke, Vermillion47 min
May 7, 6:03 PM CDTTornado WarningILXEdgar, Vermilion42 min
May 7, 6:04 PM CDTSevere Thunderstorm WarningIWXFulton, Pulaski, Starke56 min
May 7, 6:24 PM CDTTornado WarningILXEdgar51 min
May 7, 6:38 PM CDTTornado WarningINDVermillion, Vigo52 min
May 7, 6:42 PM CDTTornado WarningINDClay, Parke, Putnam, Vermillion30 min
May 7, 6:57 PM CDTTornado WarningILXEdgar25 min
May 7, 7:15 PM CDTSevere Thunderstorm WarningINDClay, Parke, Putnam, Vigo45 min
May 7, 7:23 PM CDTTornado WarningINDClay, Sullivan, Vigo52 min
May 7, 7:55 PM CDTFlash Flood WarningINDClay, Greene, Owen, Putnam, Sullivan, Vigo6 hr
May 7, 8:02 PM CDTTornado WarningINDClay, Greene, Sullivan, Vigo43 min
May 7, 8:10 PM CDTTornado WarningINDSullivan, Vigo20 min
May 7, 8:26 PM CDTSevere Thunderstorm WarningINDSullivan, Vigo20 min
May 7, 8:37 PM CDTTornado WarningINDDaviess, Greene, Martin38 min
May 7, 9:12 PM CDTTornado WarningINDGreene, Lawrence, Martin48 min
May 7, 9:45 PM CDTFlash Flood WarningINDDaviess, Greene, Knox, Lawrence, Martin6 hr

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 8.0 hours before the alert went out and 72 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, Lincoln, IL at 12:00Z on 2011-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 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, Lincoln, IL at 12:00Z on 2011-05-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 134 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1168 m above ground
0-6 km bulk shear
68 kt
0-1 km storm-relative helicity
134 m²/s²
0-3 km storm-relative helicity
351 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 7, 2:32 PM CDTMesoscale DiscussionSPCBureau, Champaign, DeWitt, Douglas, Edgar, Ford and 16 more118 min

Nearby

Severe Thunderstorm Watches in Indiana, 2011Severe Thunderstorm Watches in Illinois, 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.