Alert archive / Illinois / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 775
The Storm Prediction Center issued this severe thunderstorm watch at Aug 13, 2011, 12:12 PM CDT for 4 states. It was in force for 9 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 13, 2011, 12:12 PM CDT (17:12 UTC)
- Expired
- Aug 13, 2011, 9:00 PM CDT
- In force
- 9 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 99 counties
Champaign County, IL, Christian County, IL, Clark County, IL, Coles County, IL, Cook County, IL, Cumberland County, IL, DeKalb County, IL, DeWitt County, IL, Douglas County, IL, DuPage County, IL, Edgar County, IL, Effingham County, IL, Ford County, IL, Grundy County, IL, Iroquois County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Lake County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, Mason County, IL, McHenry County, IL, McLean County, IL, Menard County, IL, Moultrie County, IL, Peoria County, IL, Piatt County, IL, Sangamon County, IL, Shelby County, IL, Tazewell County, IL, Vermilion County, IL, Will County, IL, Woodford County, IL, Adams County, IN, Allen County, IN, Benton County, IN, Blackford County, IN, Carroll County, IN, Cass County, IN, Clinton County, IN, DeKalb County, IN, Elkhart County, IN, Fountain County, IN, Fulton County, IN, Grant County, IN, Howard County, IN, Huntington County, IN, Jasper County, IN, Jay County, IN, Kosciusko County, IN, LaGrange County, IN, Lake County, IN, LaPorte County, IN, Marshall County, IN, Miami County, IN, Newton County, IN, Noble County, IN, Porter County, IN, Pulaski County, IN, Saint Joseph County, IN, Starke County, IN, Steuben County, IN, Tippecanoe County, IN, Tipton County, IN, Wabash County, IN, Warren County, IN, Wells County, IN, White County, IN, Whitley County, IN, Allegan County, MI, Barry County, MI, Berrien County, MI, Branch County, MI, Calhoun County, MI, Cass County, MI, Clinton County, MI, Eaton County, MI, Hillsdale County, MI, Ingham County, MI, Ionia County, MI, Jackson County, MI, Kalamazoo County, MI, Kent County, MI, Ottawa County, MI, Saint Joseph County, MI, Van Buren County, MI, Allen County, OH, Defiance County, OH, Fulton County, OH, Henry County, OH, Paulding County, OH, Putnam County, OH, Van Wert County, OH, Williams County, OH
The radar
The Chicago radar (KLOT), 74 km from the middle of the area, began a volume at 17:13 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
- 60%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 95%
Warnings issued inside it
40 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 13, 12:55 PM CDT | Severe Thunderstorm Warning | LOT | Cook, Lake, McHenry | 50 min |
| Aug 13, 2:07 PM CDT | Severe Thunderstorm Warning | GRR | Kent, Ottawa | 70 min |
| Aug 13, 2:12 PM CDT | Severe Thunderstorm Warning | LOT | Cook, DuPage | 63 min |
| Aug 13, 2:21 PM CDT | Severe Thunderstorm Warning | GRR | Kent, Ottawa | 54 min |
| Aug 13, 2:23 PM CDT | Severe Thunderstorm Warning | LOT | Lee, Ogle | 67 min |
| Aug 13, 2:31 PM CDT | Severe Thunderstorm Warning | LOT | LaSalle | 34 min |
| Aug 13, 2:43 PM CDT | Severe Thunderstorm Warning | GRR | Van Buren | 65 min |
| Aug 13, 2:43 PM CDT | Severe Thunderstorm Warning | IWX | Berrien, Cass | 29 min |
| Aug 13, 2:48 PM CDT | Severe Thunderstorm Warning | LOT | DeKalb, DuPage, Kane, Kendall, Will | 57 min |
| Aug 13, 2:51 PM CDT | Severe Thunderstorm Warning | ILX | Peoria, Tazewell | 39 min |
| Aug 13, 2:54 PM CDT | Severe Thunderstorm Warning | LOT | Grundy, Will | 41 min |
| Aug 13, 3:05 PM CDT | Severe Thunderstorm Warning | ILX | Marshall, Woodford | 16 min |
| Aug 13, 3:10 PM CDT | Severe Thunderstorm Warning | IWX | LaPorte, Saint Joseph | 65 min |
| Aug 13, 3:30 PM CDT | Severe Thunderstorm Warning | ILX | McLean, Tazewell, Woodford | 45 min |
| Aug 13, 3:46 PM CDT | Severe Thunderstorm Warning | ILX | Cass, Menard, Morgan, Sangamon | 37 min |
| Aug 13, 3:51 PM CDT | Severe Thunderstorm Warning | ILX | DeWitt, Logan, McLean, Mason, Tazewell | 35 min |
| Aug 13, 3:54 PM CDT | Severe Thunderstorm Warning | ILX | Morgan, Sangamon | 66 min |
| Aug 13, 3:59 PM CDT | Severe Thunderstorm Warning | ILX | McLean | 61 min |
| Aug 13, 4:04 PM CDT | Severe Thunderstorm Warning | GRR | Calhoun, Kalamazoo | 64 min |
| Aug 13, 4:09 PM CDT | Severe Thunderstorm Warning | IWX | Branch, Hillsdale, Saint Joseph | 66 min |
| Aug 13, 4:24 PM CDT | Severe Thunderstorm Warning | LOT | Iroquois | 66 min |
| Aug 13, 4:31 PM CDT | Severe Thunderstorm Warning | ILX | DeWitt, Piatt | 59 min |
| Aug 13, 4:35 PM CDT | Severe Thunderstorm Warning | ILX | Logan, Macon | 55 min |
| Aug 13, 4:35 PM CDT | Severe Thunderstorm Warning | GRR | Jackson | 73 min |
| Aug 13, 4:47 PM CDT | Severe Thunderstorm Warning | IWX | LaPorte, Saint Joseph | 48 min |
| Aug 13, 4:47 PM CDT | Severe Thunderstorm Warning | LOT | Jasper, Lake, Porter | 29 min |
| Aug 13, 5:08 PM CDT | Severe Thunderstorm Warning | ILX | Christian, Shelby | 55 min |
| Aug 13, 5:14 PM CDT | Severe Thunderstorm Warning | IWX | LaPorte, Saint Joseph, Starke | 61 min |
| Aug 13, 5:19 PM CDT | Severe Thunderstorm Warning | GRR | Ingham | 30 min |
| Aug 13, 5:25 PM CDT | Severe Thunderstorm Warning | LOT | Benton | 50 min |
| Aug 13, 5:25 PM CDT | Tornado Warning | GRR | Jackson | 20 min |
| Aug 13, 5:49 PM CDT | Severe Thunderstorm Warning | IND | Tippecanoe, Warren | 56 min |
| Aug 13, 6:01 PM CDT | Severe Thunderstorm Warning | ILX | Edgar | 44 min |
| Aug 13, 6:08 PM CDT | Severe Thunderstorm Warning | IWX | Fulton, Marshall, Pulaski, Starke | 67 min |
| Aug 13, 6:21 PM CDT | Severe Thunderstorm Warning | IWX | Cass, Fulton, Pulaski, White | 54 min |
| Aug 13, 6:34 PM CDT | Severe Thunderstorm Warning | IND | Carroll, Clinton, Tippecanoe | 41 min |
| Aug 13, 6:35 PM CDT | Tornado Warning | IWX | Cass, White | 15 min |
| Aug 13, 7:24 PM CDT | Severe Thunderstorm Warning | IWX | Grant, Huntington, Miami, Wabash, Wells | 51 min |
| Aug 13, 7:59 PM CDT | Severe Thunderstorm Warning | IWX | Adams, Wells | 48 min |
| Aug 13, 8:13 PM CDT | Severe Thunderstorm Warning | IWX | Adams, Blackford, Jay, Wells | 46 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
Lincoln, IL (KILX), launched 12:00Z, 5.2 hours before the alert went out and 181 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
- 7333 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 88 m²/s²
- 0-3 km storm-relative helicity
- 84 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 13, 11:45 AM CDT | Mesoscale Discussion | SPC | Bureau, Champaign, Cook, DeKalb, DuPage, Ford and 16 more | 60 min |
| Aug 13, 3:29 PM CDT | Mesoscale Discussion | SPC | Bond, Champaign, Christian, Clark, Clay, Clinton and 21 more | 91 min |
| Aug 13, 6:10 PM CDT | Mesoscale Discussion | SPC | Clark, Coles, Cumberland, Douglas, Edgar, Shelby and 1 more | 95 min |
| Aug 13, 4:53 PM CDT | Mesoscale Discussion | SPC | Bartholomew, Boone, Brown, Clay, Daviess, Decatur and 26 more | 37 min |
| Aug 13, 4:57 PM CDT | Severe Thunderstorm Watch | SPC | Bartholomew, Boone, Brown, Clay, Daviess, Decatur and 26 more | 7 hr |
| Aug 13, 5:30 PM CDT | Mesoscale Discussion | SPC | Clark, Floyd, Ohio, Switzerland | 90 min |
| Aug 13, 4:28 PM CDT | Severe Thunderstorm Watch | SPC | Genesee, Lapeer, Lenawee, Livingston, Macomb, Monroe and 5 more | 4 hr |
Nearby
Severe Thunderstorm Watches in Illinois, 2011Severe Thunderstorm Watches in Indiana, 2011Severe Thunderstorm Watches in Michigan, 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.