Alert archive / Illinois / Severe Thunderstorm Watches in 2007
Severe Thunderstorm Watch 274
The Storm Prediction Center issued this severe thunderstorm watch at May 15, 2007, 11:02 AM CDT for 52 counties in Illinois; 20 counties in Missouri. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- May 15, 2007, 11:02 AM CDT (16:02 UTC)
- Expired
- May 15, 2007, 5:59 PM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 72 counties
Adams County, IL, Bond County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Champaign County, IL, Christian County, IL, Clark County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, DeWitt County, IL, Douglas County, IL, Edgar County, IL, Effingham County, IL, Fayette County, IL, Fulton County, IL, Greene County, IL, Jasper County, IL, Jersey County, IL, Knox County, IL, Lawrence County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Marshall County, IL, Mason County, IL, McLean County, IL, Menard County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Peoria County, IL, Piatt County, IL, Pike County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Stark County, IL, Tazewell County, IL, Vermilion County, IL, Washington County, IL, Woodford County, IL, Audrain County, MO, Callaway County, MO, City of Saint Louis, MO, Cole County, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Jefferson County, MO, Lincoln County, MO, Marion County, MO, Montgomery County, MO, Osage County, MO, Pike County, MO, Ralls County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Warren County, MO, Washington County, MO
The radar
The Lincoln radar (KILX), 99 km from the middle of the area, began a volume at 16:01 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
- 40%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 60%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
9 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 15, 11:41 AM CDT | Severe Thunderstorm Warning | LSX | Adams, Brown | 49 min |
| May 15, 12:30 PM CDT | Severe Thunderstorm Warning | ILX | Morgan, Sangamon | 45 min |
| May 15, 12:44 PM CDT | Severe Thunderstorm Warning | ILX | Cass, Fulton, Mason, Schuyler | 46 min |
| May 15, 1:14 PM CDT | Severe Thunderstorm Warning | ILX | Christian, Sangamon | 31 min |
| May 15, 1:24 PM CDT | Severe Thunderstorm Warning | ILX | DeWitt, Logan | 34 min |
| May 15, 1:29 PM CDT | Severe Thunderstorm Warning | ILX | DeWitt, Logan, Macon, Sangamon | 46 min |
| May 15, 1:54 PM CDT | Severe Thunderstorm Warning | ILX | DeWitt, McLean, Macon, Piatt | 51 min |
| May 15, 2:19 PM CDT | Severe Thunderstorm Warning | ILX | Champaign | 41 min |
| May 15, 3:44 PM CDT | Severe Thunderstorm Warning | LSX | Iron, Saint Francois | 29 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, 4.0 hours before the alert went out and 155 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
- 20 J/kg
- Mixed-layer CIN
- -273 J/kg
- Mixed-layer LCL
- 1998 m above ground
- 0-6 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- -6 m²/s²
- 0-3 km storm-relative helicity
- 49 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 15, 12:15 PM CDT | Mesoscale Discussion | SPC | Champaign, Clark, Coles, Crawford, Cumberland, Douglas and 5 more | 90 min |
| May 15, 12:53 PM CDT | Severe Thunderstorm Watch | SPC | Ford, Iroquois, Kankakee, Livingston | 7 hr |
| May 15, 3:30 PM CDT | Mesoscale Discussion | SPC | Bond, Champaign, Christian, Clay, Clinton, Coles and 32 more | 90 min |
| May 15, 3:32 PM CDT | Mesoscale Discussion | SPC | Ford, Iroquois, Kankakee, Vermilion | 58 min |
| May 15, 4:58 PM CDT | Mesoscale Discussion | SPC | Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 14 more | 62 min |
| May 15, 5:25 PM CDT | Mesoscale Discussion | SPC | Clark, Clay, Coles, Crawford, Cumberland, Edgar and 8 more | 35 min |
| May 15, 11:30 AM CDT | Mesoscale Discussion | SPC | Barry, Christian, Dade, Dallas, Douglas, Greene and 13 more | 90 min |
Nearby
Severe Thunderstorm Watches in Illinois, 2007Severe Thunderstorm Watches in Missouri, 2007Every severe thunderstorm watch in 2007
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.