Alert archive / Illinois / Severe Thunderstorm Watches in 2004
Severe Thunderstorm Watch 702
The Storm Prediction Center issued this severe thunderstorm watch at Aug 3, 2004, 7:55 PM CDT for 27 counties in Illinois; 4 counties in Indiana; Allegan County, Berrien County, Van Buren County, Michigan. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 3, 2004, 7:55 PM CDT (00:55 UTC)
- Expired
- Aug 4, 2004, 1:00 AM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
All 34 counties
Boone County, IL, Bureau County, IL, Cook County, IL, DeKalb County, IL, DuPage County, IL, Ford County, IL, Fulton 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, Marshall County, IL, McHenry County, IL, McLean County, IL, Ogle County, IL, Peoria County, IL, Putnam County, IL, Stark County, IL, Tazewell County, IL, Will County, IL, Winnebago County, IL, Woodford County, IL, Jasper County, IN, Lake County, IN, Newton County, IN, Porter County, IN, Allegan County, MI, Berrien County, MI, Van Buren County, MI
The radar
The Chicago radar (KLOT), 75 km from the middle of the area, began a volume at 00:56 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.
Warnings issued inside it
14 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 3, 8:05 PM CDT | Severe Thunderstorm Warning | LOT | Lee, Ogle, Winnebago | 85 min |
| Aug 3, 9:10 PM CDT | Severe Thunderstorm Warning | LOT | Boone, DeKalb | 65 min |
| Aug 3, 9:16 PM CDT | Severe Thunderstorm Warning | LOT | LaSalle | 89 min |
| Aug 3, 9:40 PM CDT | Severe Thunderstorm Warning | LOT | Kane, Kendall | 65 min |
| Aug 3, 9:53 PM CDT | Severe Thunderstorm Warning | LOT | Grundy | 52 min |
| Aug 3, 9:58 PM CDT | Severe Thunderstorm Warning | LOT | Cook, DuPage, Will | 92 min |
| Aug 3, 10:35 PM CDT | Severe Thunderstorm Warning | LOT | Kankakee | 55 min |
| Aug 3, 10:45 PM CDT | Severe Thunderstorm Warning | LOT | Lake, Porter | 90 min |
| Aug 3, 10:59 PM CDT | Severe Thunderstorm Warning | LOT | Jasper, Newton | 76 min |
| Aug 3, 11:04 PM CDT | Severe Thunderstorm Warning | IWX | Berrien | 71 min |
| Aug 3, 11:16 PM CDT | Severe Thunderstorm Warning | LOT | Ford, Livingston | 44 min |
| Aug 3, 11:36 PM CDT | Severe Thunderstorm Warning | LOT | Iroquois, Kankakee | 54 min |
| Aug 3, 11:50 PM CDT | Severe Thunderstorm Warning | ILX | Stark | 40 min |
| Aug 4, 12:24 AM CDT | Severe Thunderstorm Warning | ILX | Marshall | 66 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 00:00Z, 0.9 hours before the alert went out and 112 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
- 4276 J/kg
- Mixed-layer CIN
- -9 J/kg
- Mixed-layer LCL
- 860 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 113 m²/s²
- 0-3 km storm-relative helicity
- 138 m²/s²
- Significant tornado parameter
- 2.0
- Supercell composite
- 11.6
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 3, 7:38 PM CDT | Mesoscale Discussion | SPC | Bureau, Cook, DeKalb, DuPage, Ford, Grundy and 14 more | 67 min |
| Aug 3, 8:19 PM CDT | Mesoscale Discussion | SPC | Carroll, Henry, Jo Daviess, Knox, Mercer, Rock Island and 2 more | 56 min |
| Aug 3, 9:45 PM CDT | Severe Thunderstorm Watch | SPC | Fulton, Hancock, Henderson, Henry, Knox, McDonough and 3 more | 5 hr |
| Aug 3, 9:52 PM CDT | Mesoscale Discussion | SPC | Cook, DuPage, Grundy, Kane, Kendall, Lake and 3 more | 53 min |
| Aug 3, 10:38 PM CDT | Mesoscale Discussion | SPC | Adams, Brown, Calhoun, Cass, Greene, Jersey and 3 more | 67 min |
| Aug 3, 11:30 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Brown, Calhoun, Cass, Champaign, Christian and 32 more | 6 hr |
| Aug 4, 1:42 AM CDT | Mesoscale Discussion | SPC | Fulton, Henderson, Jersey, Livingston, McDonough, Mason and 5 more | 2 hr |
| Aug 4, 3:52 AM CDT | Mesoscale Discussion | SPC | Adams, Brown, Calhoun, Cass, Champaign, Christian and 32 more | 53 min |
| Aug 4, 3:39 PM CDT | Mesoscale Discussion | SPC | Hardin, Massac, Pope | 96 min |
| Aug 3, 10:35 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Allen, Benton, Blackford, Carroll, Cass and 26 more | 5 hr |
| Aug 3, 11:47 PM CDT | Mesoscale Discussion | SPC | Benton, Carroll, Cass, Elkhart, Fulton, Kosciusko and 9 more | 58 min |
| Aug 4, 1:15 AM CDT | Mesoscale Discussion | SPC | Adams, Allen, Benton, Blackford, Carroll, Cass and 26 more | 90 min |
| Aug 4, 5:44 AM CDT | Mesoscale Discussion | SPC | Adams, Allen, Blackford, Boone, Carroll, Clay and 28 more | 2 hr |
| Aug 4, 1:01 PM CDT | Mesoscale Discussion | SPC | Clark, Crawford, Dubois, Floyd, Harrison, Jefferson and 7 more | 89 min |
| Aug 4, 1:30 PM CDT | Severe Thunderstorm Watch | SPC | Clark, Crawford, Floyd, Harrison, Perry | 6 hr |
Nearby
Severe Thunderstorm Watches in Illinois, 2004Severe Thunderstorm Watches in Indiana, 2004Severe Thunderstorm Watches in Michigan, 2004Every severe thunderstorm watch in 2004
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.