Alert archive / Illinois / Severe Thunderstorm Watches in 2003
Severe Thunderstorm Watch 642
The Storm Prediction Center issued this severe thunderstorm watch at Jul 5, 2003, 3:40 AM CDT for 4 states. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 5, 2003, 3:40 AM CDT (08:40 UTC)
- Expired
- Jul 5, 2003, 8:00 AM CDT
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
All 28 counties
Boone County, IL, Bureau County, IL, Cook County, IL, DeKalb County, IL, DuPage County, IL, Grundy County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Lake County, IL, LaSalle County, IL, Lee County, IL, McHenry County, IL, Ogle County, IL, Putnam County, IL, Will County, IL, Winnebago County, IL, Lake County, IN, Muskegon County, MI, Dodge County, WI, Jefferson County, WI, Kenosha County, WI, Milwaukee County, WI, Racine County, WI, Rock County, WI, Walworth County, WI, Washington County, WI, Waukesha County, WI
The radar
The Chicago radar (KLOT), 56 km from the middle of the area, began a volume at 08:43 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
4 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 5, 3:47 AM CDT | Severe Thunderstorm Warning | LOT | Lee, Ogle, Winnebago | 58 min |
| Jul 5, 4:27 AM CDT | Severe Thunderstorm Warning | LOT | Boone, McHenry | 48 min |
| Jul 5, 5:02 AM CDT | Severe Thunderstorm Warning | LOT | Cook, Kane, Lake | 43 min |
| Jul 5, 5:59 AM CDT | Severe Thunderstorm Warning | LOT | Lake, Porter | 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
Davenport, (KDVN), launched 00:00Z, 8.7 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
- 135 J/kg
- Mixed-layer CIN
- -351 J/kg
- Mixed-layer LCL
- 2353 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 93 m²/s²
- 0-3 km storm-relative helicity
- 167 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 4, 8:58 PM CDT | Mesoscale Discussion | SPC | DuPage, Grundy, Iroquois, Kane, Kankakee, Kendall and 1 more | 62 min |
| Jul 4, 10:09 PM CDT | Mesoscale Discussion | SPC | Brown, Cass, Champaign, DeWitt, Douglas, Ford and 20 more | 2 hr |
| Jul 4, 10:45 PM CDT | Mesoscale Discussion | SPC | Jo Daviess, Rock Island | 90 min |
| Jul 4, 11:25 PM CDT | Severe Thunderstorm Watch | SPC | Carroll, Henderson, Henry, Jo Daviess, Knox, Mercer and 6 more | 7 hr |
| Jul 5, 2:31 AM CDT | Mesoscale Discussion | SPC | Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 27 more | 89 min |
| Jul 5, 5:43 AM CDT | Mesoscale Discussion | SPC | Cook, Kankakee, Lake, Will | 92 min |
| Jul 5, 12:55 PM CDT | Mesoscale Discussion | SPC | Champaign, Christian, Clark, Coles, Crawford, Cumberland and 14 more | 3 hr |
| Jul 5, 4:34 PM CDT | Mesoscale Discussion | SPC | Champaign, Ford, Iroquois, Vermilion | 56 min |
| Jul 5, 5:18 PM CDT | Mesoscale Discussion | SPC | Cass, DeWitt, Fulton, Hancock, Henderson, Henry and 16 more | 57 min |
| Jul 5, 5:55 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Brown, Cass, Champaign, Christian, Clark and 36 more | 6 hr |
| Jul 5, 6:00 AM CDT | Severe Thunderstorm Watch | SPC | Elkhart, LaGrange, LaPorte, Porter, Saint Joseph, Steuben | 3 hr |
| Jul 5, 7:12 AM CDT | Mesoscale Discussion | SPC | Adams, Allen, DeKalb, Elkhart, Fulton, Huntington and 10 more | 93 min |
| Jul 5, 4:55 PM CDT | Severe Thunderstorm Watch | SPC | Bartholomew, Benton, Boone, Brown, Carroll, Clay and 35 more | 4 hr |
Nearby
Severe Thunderstorm Watches in Illinois, 2003Severe Thunderstorm Watches in Wisconsin, 2003Severe Thunderstorm Watches in Indiana, 2003Every severe thunderstorm watch in 2003
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.