Alert archive / Illinois / Severe Thunderstorm Watches in 2002

Severe Thunderstorm Watch 145

April 24, 200236 counties in Illinois; 9 counties in Iowa; 30 counties in Missouri

The Storm Prediction Center issued this severe thunderstorm watch at Apr 24, 2002, 10:15 AM CDT for 36 counties in Illinois; 9 counties in Iowa; 30 counties in Missouri. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Apr 24, 2002, 10:15 AM CDT (15:15 UTC)
Expired
Apr 24, 2002, 3:00 PM CDT
In force
5 hr
Issued by
the Storm Prediction Center
All 75 counties

Davis County, IA, Des Moines County, IA, Henry County, IA, Jefferson County, IA, Keokuk County, IA, Lee County, IA, Louisa County, IA, Van Buren County, IA, Washington County, IA, Adams County, IL, Bond County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Christian County, IL, Clinton County, IL, DeWitt County, IL, Fulton County, IL, Greene County, IL, Hancock County, IL, Henderson County, IL, Jersey County, IL, Knox County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Mercer County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Peoria County, IL, Piatt County, IL, Pike County, IL, Randolph County, IL, Saint Clair County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Tazewell County, IL, Warren County, IL, Adair County, MO, Audrain County, MO, Boone County, MO, Callaway County, MO, Chariton County, MO, City of Saint Louis, MO, Clark County, MO, Franklin County, MO, Gasconade County, MO, Howard County, MO, Jefferson County, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Linn County, MO, Macon County, MO, Marion County, MO, Monroe County, MO, Montgomery County, MO, Pike County, MO, Ralls County, MO, Randolph County, MO, Saint Charles County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Saline County, MO, Schuyler County, MO, Scotland County, MO, Shelby County, MO, Warren County, MO

The radar

The St Louis radar (KLSX), 121 km from the middle of the area, began a volume at 15:18 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

12 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 24, 11:30 AM CDTSevere Thunderstorm WarningEAXSchuyler30 min
Apr 24, 11:33 AM CDTSevere Thunderstorm WarningDMXDavis42 min
Apr 24, 11:39 AM CDTSevere Thunderstorm WarningEAXAdair, Putnam51 min
Apr 24, 12:08 PM CDTSevere Thunderstorm WarningEAXMacon67 min
Apr 24, 12:31 PM CDTSevere Thunderstorm WarningDVNClark44 min
Apr 24, 12:40 PM CDTSevere Thunderstorm WarningDVNMercer50 min
Apr 24, 12:56 PM CDTSevere Thunderstorm WarningILXMorgan, Scott64 min
Apr 24, 1:26 PM CDTSevere Thunderstorm WarningILXSchuyler64 min
Apr 24, 2:13 PM CDTSevere Thunderstorm WarningILXSangamon47 min
Apr 24, 2:19 PM CDTSevere Thunderstorm WarningILXCass41 min
Apr 24, 2:51 PM CDTSevere Thunderstorm WarningILXMenard39 min
Apr 24, 2:55 PM CDTSevere Thunderstorm WarningILXMason50 min

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 3.3 hours before the alert went out and 237 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.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 2002-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 28 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 2002-04-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 99 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
28 J/kg
Mixed-layer CIN
-364 J/kg
Mixed-layer LCL
846 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
99 m²/s²
0-3 km storm-relative helicity
112 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 24, 1:30 PM CDTSevere Thunderstorm WatchSPCBoone, Cook, DeKalb, DuPage, Ford, Grundy and 17 more6 hr
Apr 24, 2:30 PM CDTTornado WatchSPCAdams, Alexander, Bond, Brown, Calhoun, Cass and 49 more6 hr
Apr 24, 3:30 PM CDTTornado WatchSPCGallatin, Hardin5 hr
Apr 24, 7:30 AM CDTSevere Thunderstorm WatchSPCAdair, Adams, Appanoose, Audubon, Boone, Calhoun and 34 more6 hr
Apr 24, 5:30 PM CDTSevere Thunderstorm WatchSPCDunklin, Pemiscot5 hr

Nearby

Severe Thunderstorm Watches in Illinois, 2002Severe Thunderstorm Watches in Missouri, 2002Severe Thunderstorm Watches in Iowa, 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.