Alert archive / Illinois / Severe Thunderstorm Watches in 2002
Severe Thunderstorm Watch 290
The Storm Prediction Center issued this severe thunderstorm watch at May 12, 2002, 2:45 PM CDT for 29 counties in Illinois; 10 counties in Missouri. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- May 12, 2002, 2:45 PM CDT (19:45 UTC)
- Expired
- May 12, 2002, 8:00 PM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
All 39 counties
Bond County, IL, Calhoun County, IL, Christian County, IL, Clark County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, Edgar County, IL, Edwards County, IL, Effingham County, IL, Fayette County, IL, Greene County, IL, Jasper County, IL, Jefferson County, IL, Jersey County, IL, Lawrence County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Montgomery County, IL, Richland County, IL, Saint Clair County, IL, Shelby County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, City of Saint Louis, MO, Franklin County, MO, Gasconade County, MO, Jefferson County, MO, Lincoln County, MO, Montgomery County, MO, Pike County, MO, Saint Charles County, MO, Saint Louis County, MO, Warren County, MO
The radar
The St Louis radar (KLSX), 67 km from the middle of the area, began a volume at 19:47 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
3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 12, 4:29 PM CDT | Flash Flood Warning | LSX | Bond, Jersey, Macoupin, Madison, Montgomery | 6 hr |
| May 12, 5:09 PM CDT | Flash Flood Warning | LSX | Fayette | 5 hr |
| May 12, 5:21 PM CDT | Severe Thunderstorm Warning | ILX | Effingham, Jasper | 39 min |
The nearest sounding before it
Lincoln, IL (KILX), launched 12:00Z, 7.8 hours before the alert went out and 176 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
- 77 J/kg
- Mixed-layer CIN
- -142 J/kg
- Mixed-layer LCL
- 829 m above ground
- 0-6 km bulk shear
- 75 kt
- 0-1 km storm-relative helicity
- 163 m²/s²
- 0-3 km storm-relative helicity
- -16 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 12, 6:15 PM CDT | Severe Thunderstorm Watch | SPC | Clay, Clinton, Edwards, Franklin, Gallatin, Hamilton and 16 more | 5 hr |
| May 11, 7:00 PM CDT | Tornado Watch | SPC | Atchison, Gentry, Grundy, Harrison, Holt, Mercer and 2 more | 5 hr |
| May 12, 12:30 AM CDT | Severe Thunderstorm Watch | SPC | Barton, Bates, Henry, Jasper, St. Clair, Vernon | 6 hr |
| May 12, 1:15 PM CDT | Severe Thunderstorm Watch | SPC | Barry, Barton, Camden, Cedar, Christian, Dade and 17 more | 6 hr |
Nearby
Severe Thunderstorm Watches in Illinois, 2002Severe Thunderstorm Watches in Missouri, 2002Every severe thunderstorm watch in 2002
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.