Alert archive / Illinois / Severe Thunderstorm Watches in 1998
Severe Thunderstorm Watch 754
The Storm Prediction Center issued this severe thunderstorm watch at Jul 19, 1998, 4:15 AM CDT for 4 states. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 19, 1998, 4:15 AM CDT (09:15 UTC)
- Expired
- Jul 19, 1998, 8:00 AM CDT
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
All 24 counties
Cook County, IL, DeKalb County, IL, DuPage County, IL, Grundy County, IL, Iroquois County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Lake County, IL, LaSalle County, IL, Livingston County, IL, McHenry County, IL, Will County, IL, Benton County, IN, Jasper County, IN, Lake County, IN, Newton County, IN, Porter County, IN, Berrien County, MI, Kenosha County, WI, Milwaukee County, WI, Racine County, WI, Walworth County, WI, Waukesha County, WI
The radar
The Chicago radar (KLOT), 15 km from the middle of the area, began a volume at 09:16 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 19, 4:15 AM CDT | Severe Thunderstorm Warning | MKX | Walworth | 50 min |
| Jul 19, 4:23 AM CDT | Severe Thunderstorm Warning | LOT | DeKalb, Kane | 97 min |
| Jul 19, 4:23 AM CDT | Severe Thunderstorm Warning | LOT | DeKalb, Kane | 37 min |
| Jul 19, 4:45 AM CDT | Severe Thunderstorm Warning | LOT | Cook, DuPage, Kendall, Will | 60 min |
The nearest sounding before it
Davenport, (KDVN), launched 00:00Z, 9.3 hours before the alert went out and 200 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
- 1603 J/kg
- Mixed-layer CIN
- -62 J/kg
- Mixed-layer LCL
- 1209 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- 35 m²/s²
- 0-3 km storm-relative helicity
- 75 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 2.2
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 19, 1:30 AM CDT | Severe Thunderstorm Watch | SPC | Boone, Bureau, Carroll, Henry, Jo Daviess, Lee and 7 more | 6 hr |
| Jul 19, 3:15 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Allen, Benton, Blackford, Boone, Carroll and 33 more | 6 hr |
| Jul 18, 10:30 PM CDT | Severe Thunderstorm Watch | SPC | Buffalo, Chippewa, Dunn, Eau Claire, Pepin, Pierce and 2 more | 6 hr |
Nearby
Severe Thunderstorm Watches in Illinois, 1998Severe Thunderstorm Watches in Indiana, 1998Severe Thunderstorm Watches in Wisconsin, 1998Every severe thunderstorm watch in 1998
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.