Alert archive / Illinois / Severe Thunderstorm Watches in 2003

Severe Thunderstorm Watch 268

May 6, 20034 states

The Storm Prediction Center issued this severe thunderstorm watch at May 6, 2003, 11:55 AM CDT for 4 states. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
May 6, 2003, 11:55 AM CDT (16:55 UTC)
Expired
May 6, 2003, 4:00 PM CDT
In force
4 hr
Issued by
the Storm Prediction Center
All 62 counties

Bond County, IL, Clay County, IL, Clinton County, IL, Crawford County, IL, Edwards County, IL, Effingham County, IL, Fayette County, IL, Franklin County, IL, Gallatin County, IL, Hamilton County, IL, Jackson County, IL, Jasper County, IL, Jefferson County, IL, Lawrence County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Perry County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Saline County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Daviess County, IN, Dubois County, IN, Gibson County, IN, Greene County, IN, Knox County, IN, Pike County, IN, Posey County, IN, Spencer County, IN, Sullivan County, IN, Vanderburgh County, IN, Warrick County, IN, Hancock County, KY, Henderson County, KY, City of Saint Louis, MO, Cole County, MO, Crawford County, MO, Dent County, MO, Franklin County, MO, Gasconade County, MO, Iron County, MO, Jefferson County, MO, Madison County, MO, Maries County, MO, Osage County, MO, Perry County, MO, Phelps County, MO, Pulaski County, MO, Reynolds County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Texas County, MO, Warren County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 64 km from the middle of the area, began a volume at 16:55 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

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

IssuedProductOfficeCountiesLasted
May 6, 11:58 AM CDTSevere Thunderstorm WarningPAHJefferson47 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

Springfield, MO (KSGF), launched 12:00Z, 4.9 hours before the alert went out and 361 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, Springfield, MO at 12:00Z on 2003-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 34 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, Springfield, MO at 12:00Z on 2003-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 86 square meters per square second.1939587897Sfc1 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
34 J/kg
Mixed-layer CIN
-216 J/kg
Mixed-layer LCL
1877 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
86 m²/s²
0-3 km storm-relative helicity
115 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 5, 10:58 PM CDTMesoscale DiscussionSPCAlexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 9 more2 hr
May 6, 9:37 AM CDTMesoscale DiscussionSPCBond, Clark, Clay, Clinton, Crawford, Cumberland and 15 more113 min
May 6, 1:23 PM CDTMesoscale DiscussionSPCBond, Clay, Clinton, Crawford, Edwards, Effingham and 17 more2 hr
May 6, 5:08 PM CDTMesoscale DiscussionSPCBond, Calhoun, Clinton, Fayette, Jackson, Jefferson and 9 more2 hr
May 6, 5:33 PM CDTMesoscale DiscussionSPCBond, Calhoun, Clinton, Fayette, Jackson, Jefferson and 9 more117 min
May 6, 5:40 PM CDTTornado WatchSPCAlexander, Bond, Clay, Clinton, Crawford, Edwards and 28 more6 hr
May 6, 10:55 AM CDTMesoscale DiscussionSPCBartholomew, Brown, Clark, Crawford, Dearborn, Decatur and 23 more2 hr
May 6, 12:45 PM CDTMesoscale DiscussionSPCBarren, Breckinridge, Bullitt, Butler, Casey, Daviess and 20 more2 hr
May 6, 1:50 AM CDTTornado WatchSPCDunklin, Pemiscot6 hr
May 6, 6:49 AM CDTMesoscale DiscussionSPCBarton, Bates, Benton, Caldwell, Camden, Carroll and 27 more3 hr
May 6, 7:55 AM CDTSevere Thunderstorm WatchSPCBarton, Bates, Benton, Camden, Cass, Cedar and 22 more5 hr
May 6, 10:32 AM CDTMesoscale DiscussionSPCMcDonald118 min
May 6, 11:29 AM CDTMesoscale DiscussionSPCBarton, Bates, Benton, Cass, Cedar, Clay and 18 more2 hr
May 6, 11:40 AM CDTTornado WatchSPCBarry, Barton, Bates, Benton, Cass, Cedar and 20 more7 hr
May 6, 2:15 PM CDTTornado WatchSPCBoone, Callaway, Camden, Carter, Cole, Cooper and 27 more5 hr
May 6, 3:42 PM CDTMesoscale DiscussionSPCBarton, Bates, Benton, Boone, Callaway, Camden and 20 more2 hr
May 6, 6:35 PM CDTTornado WatchSPCBarry, Barton, Camden, Carter, Cedar, Christian and 31 more5 hr

Nearby

Severe Thunderstorm Watches in Illinois, 2003Severe Thunderstorm Watches in Missouri, 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.