Alert archive / Illinois / Severe Thunderstorm Watches in 2007
Severe Thunderstorm Watch 647
The Storm Prediction Center issued this severe thunderstorm watch at Aug 24, 2007, 12:19 PM CDT for 43 counties in Illinois; 37 counties in Missouri. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 24, 2007, 12:19 PM CDT (17:19 UTC)
- Expired
- Aug 24, 2007, 8:00 PM CDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 80 counties
Bond 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, Greene County, IL, Jasper County, IL, Jersey County, IL, Lawrence County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Mason County, IL, McLean County, IL, Menard County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Piatt County, IL, Pike County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Sangamon County, IL, Scott County, IL, Shelby County, IL, Tazewell County, IL, Vermilion County, IL, Washington County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, Camden County, MO, City of Saint Louis, MO, Cole County, MO, Crawford County, MO, Dallas County, MO, Dent County, MO, Franklin County, MO, Gasconade County, MO, Iron County, MO, Jefferson County, MO, Laclede County, MO, Lincoln County, MO, Madison County, MO, Maries County, MO, Miller County, MO, Moniteau County, MO, Montgomery County, MO, Morgan County, MO, Osage County, MO, Phelps County, MO, Pike County, MO, Pulaski County, MO, Ralls County, MO, Reynolds County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Shannon County, MO, Texas County, MO, Warren County, MO, Washington County, MO, Webster County, MO, Wright County, MO
The radar
The St Louis radar (KLSX), 27 km from the middle of the area, began a volume at 17:22 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
- 40%
- 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
- 95%
Warnings issued inside it
28 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 24, 1:00 PM CDT | Severe Thunderstorm Warning | SGF | Laclede | 45 min |
| Aug 24, 1:43 PM CDT | Severe Thunderstorm Warning | SGF | Pulaski | 45 min |
| Aug 24, 1:48 PM CDT | Severe Thunderstorm Warning | LSX | Franklin, Gasconade, Warren | 42 min |
| Aug 24, 2:08 PM CDT | Severe Thunderstorm Warning | SGF | Webster | 67 min |
| Aug 24, 2:21 PM CDT | Severe Thunderstorm Warning | LSX | Franklin, Jefferson, Saint Louis | 39 min |
| Aug 24, 2:28 PM CDT | Severe Thunderstorm Warning | SGF | Phelps | 62 min |
| Aug 24, 2:40 PM CDT | Flash Flood Warning | SGF | Christian, Laclede, Pulaski, Stone, Webster, Wright | 6 hr |
| Aug 24, 2:43 PM CDT | Severe Thunderstorm Warning | LSX | Madison | 47 min |
| Aug 24, 2:52 PM CDT | Tornado Warning | LSX | Crawford | 38 min |
| Aug 24, 2:52 PM CDT | Tornado Warning | SGF | Phelps | 23 min |
| Aug 24, 2:57 PM CDT | Severe Thunderstorm Warning | LSX | Saint Clair | 33 min |
| Aug 24, 3:00 PM CDT | Severe Thunderstorm Warning | LSX | Clinton, Saint Clair | 30 min |
| Aug 24, 3:24 PM CDT | Severe Thunderstorm Warning | LSX | Macoupin, Madison, Montgomery | 32 min |
| Aug 24, 3:24 PM CDT | Severe Thunderstorm Warning | LSX | Madison, Saint Clair | 39 min |
| Aug 24, 3:26 PM CDT | Severe Thunderstorm Warning | LSX | Bond, Clinton, Fayette, Marion | 49 min |
| Aug 24, 3:39 PM CDT | Severe Thunderstorm Warning | SGF | Phelps, Pulaski, Texas | 66 min |
| Aug 24, 3:43 PM CDT | Severe Thunderstorm Warning | ILX | Champaign | 28 min |
| Aug 24, 3:54 PM CDT | Severe Thunderstorm Warning | LSX | Bond, Clinton, Madison | 51 min |
| Aug 24, 4:05 PM CDT | Severe Thunderstorm Warning | LSX | Fayette, Marion | 40 min |
| Aug 24, 4:08 PM CDT | Severe Thunderstorm Warning | SGF | Dent | 67 min |
| Aug 24, 4:16 PM CDT | Severe Thunderstorm Warning | LSX | Crawford, Washington | 44 min |
| Aug 24, 4:24 PM CDT | Severe Thunderstorm Warning | LSX | Fayette | 33 min |
| Aug 24, 4:30 PM CDT | Tornado Warning | LSX | Crawford, Washington | 26 min |
| Aug 24, 4:31 PM CDT | Severe Thunderstorm Warning | ILX | Clay, Effingham | 59 min |
| Aug 24, 4:59 PM CDT | Severe Thunderstorm Warning | LSX | Jefferson, Sainte Genevieve, Saint Francois, Washington | 46 min |
| Aug 24, 5:02 PM CDT | Severe Thunderstorm Warning | ILX | Cumberland, Jasper | 58 min |
| Aug 24, 5:31 PM CDT | Severe Thunderstorm Warning | ILX | Clark, Crawford | 59 min |
| Aug 24, 5:54 PM CDT | Severe Thunderstorm Warning | ILX | Clark, Edgar | 51 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, 5.3 hours before the alert went out and 229 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
- 1385 J/kg
- Mixed-layer CIN
- -74 J/kg
- Mixed-layer LCL
- 871 m above ground
- 0-6 km bulk shear
- 45 kt
- 0-1 km storm-relative helicity
- 106 m²/s²
- 0-3 km storm-relative helicity
- 87 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.3
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 23, 7:10 PM CDT | Severe Thunderstorm Watch | SPC | Bureau, Cook, Ford, Fulton, Grundy, Hancock and 20 more | 5 hr |
| Aug 23, 11:07 PM CDT | Mesoscale Discussion | SPC | Bureau, Grundy, Henderson, Henry, Kankakee, Kendall and 11 more | 53 min |
| Aug 24, 11:12 AM CDT | Mesoscale Discussion | SPC | Bond, Calhoun, Christian, Clay, Clinton, Coles and 24 more | 93 min |
| Aug 24, 2:44 PM CDT | Mesoscale Discussion | SPC | Bond, Champaign, Christian, Clark, Clay, Clinton and 34 more | 91 min |
| Aug 24, 3:04 PM CDT | Severe Thunderstorm Watch | SPC | Ford, Iroquois | 7 hr |
| Aug 24, 5:50 PM CDT | Mesoscale Discussion | SPC | Bond, Champaign, Christian, Clark, Clay, Clinton and 39 more | 85 min |
| Aug 23, 7:47 PM CDT | Mesoscale Discussion | SPC | Andrew, Atchison, Buchanan, DeKalb, Gentry, Harrison and 5 more | 118 min |
| Aug 23, 7:55 PM CDT | Mesoscale Discussion | SPC | Andrew, Atchison, Buchanan, DeKalb, Gentry, Harrison and 5 more | 2 hr |
| Aug 23, 11:01 PM CDT | Mesoscale Discussion | SPC | Andrew, Atchison, Buchanan, Daviess, DeKalb, Gentry and 9 more | 119 min |
| Aug 24, 3:05 AM CDT | Mesoscale Discussion | SPC | Andrew, Buchanan, Caldwell, Carroll, Clay, Clinton and 6 more | 115 min |
| Aug 24, 1:31 PM CDT | Mesoscale Discussion | SPC | Barry, Barton, Christian, Dade, Greene, Jasper and 5 more | 89 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.