Alert archive / Illinois / Severe Thunderstorm Watches in 1997
Severe Thunderstorm Watch 664
The Storm Prediction Center issued this severe thunderstorm watch at Jul 27, 1997, 4:00 PM CDT for 40 counties in Illinois; 12 counties in Iowa; Clark County, Missouri. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 27, 1997, 4:00 PM CDT (21:00 UTC)
- Expired
- Jul 27, 1997, 10:00 PM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
All 53 counties
Cedar County, IA, Clinton County, IA, Des Moines County, IA, Henry County, IA, Johnson County, IA, Jones County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Muscatine County, IA, Scott County, IA, Washington County, IA, Bureau County, IL, Cass County, IL, Champaign County, IL, Coles County, IL, DeWitt County, IL, Douglas County, IL, Edgar County, IL, Ford County, IL, Fulton County, IL, Grundy County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Iroquois County, IL, Kankakee County, IL, Knox County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Mercer County, IL, Moultrie County, IL, Peoria County, IL, Piatt County, IL, Putnam County, IL, Rock Island County, IL, Schuyler County, IL, Stark County, IL, Tazewell County, IL, Vermilion County, IL, Warren County, IL, Whiteside County, IL, Will County, IL, Woodford County, IL, Clark County, MO
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 |
|---|---|---|---|---|
| Jul 27, 4:02 PM CDT | Tornado Warning | DVN | Cedar | 58 min |
| Jul 27, 4:16 PM CDT | Tornado Warning | DVN | Scott | 64 min |
| Jul 27, 4:22 PM CDT | Tornado Warning | DVN | Clinton | 63 min |
| Jul 27, 4:51 PM CDT | Severe Thunderstorm Warning | DVN | Rock Island, Whiteside | 64 min |
| Jul 27, 5:08 PM CDT | Severe Thunderstorm Warning | DVN | Henry | 62 min |
| Jul 27, 6:14 PM CDT | Severe Thunderstorm Warning | LSX | Clark | 46 min |
| Jul 27, 6:57 PM CDT | Severe Thunderstorm Warning | DVN | McDonough | 63 min |
| Jul 27, 7:23 PM CDT | Severe Thunderstorm Warning | ILX | Mason | 37 min |
| Jul 27, 8:21 PM CDT | Severe Thunderstorm Warning | ILX | Tazewell | 39 min |
The nearest sounding before it
Davenport, (KDVN), launched 12:00Z, 9.0 hours before the alert went out and 61 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
- 2407 J/kg
- Mixed-layer CIN
- -105 J/kg
- Mixed-layer LCL
- 1367 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- 8 m²/s²
- 0-3 km storm-relative helicity
- 41 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 26, 7:15 PM CDT | Severe Thunderstorm Watch | SPC | Cook, DuPage, Kendall, Lake, Will | 6 hr |
| Jul 27, 8:45 AM CDT | Severe Thunderstorm Watch | SPC | Boone, Cook, DeKalb, DuPage, Kane, Kendall and 5 more | 4 hr |
Nearby
Severe Thunderstorm Watches in Illinois, 1997Severe Thunderstorm Watches in Iowa, 1997Severe Thunderstorm Watches in Missouri, 1997Every severe thunderstorm watch in 1997
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.