Alert archive / Illinois / Severe Thunderstorm Watches in 2003

Severe Thunderstorm Watch 241

May 4, 200339 counties in Illinois; 23 counties in Missouri

The Storm Prediction Center issued this severe thunderstorm watch at May 4, 2003, 11:05 PM CDT for 39 counties in Illinois; 23 counties in Missouri. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
May 4, 2003, 11:05 PM CDT (04:05 UTC)
Expired
May 5, 2003, 4:00 AM CDT
In force
5 hr
Issued by
the Storm Prediction Center
All 62 counties

Adams County, IL, Bond County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Christian County, IL, Clark County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, Douglas 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, Macon County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Pike County, IL, Richland County, IL, Saint Clair County, IL, Sangamon County, IL, Scott County, IL, Shelby County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Cole County, MO, Franklin County, MO, Gasconade County, MO, Howard County, MO, Jefferson County, MO, Lincoln County, MO, Macon County, MO, Marion County, MO, Moniteau County, MO, Monroe County, MO, Montgomery County, MO, Osage County, MO, Pike County, MO, Ralls County, MO, Randolph County, MO, Saint Charles County, MO, Saint Louis County, MO, Shelby County, MO, Warren County, MO

The radar

The St Louis radar (KLSX), 27 km from the middle of the area, began a volume at 04:08 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.

IssuedProductOfficeCountiesLasted
May 5, 12:16 AM CDTSevere Thunderstorm WarningILXEffingham44 min
May 5, 12:55 AM CDTSevere Thunderstorm WarningILXJasper35 min
May 5, 1:06 AM CDTSevere Thunderstorm WarningILXCrawford, Richland39 min
May 5, 2:12 AM CDTSevere Thunderstorm WarningPAHWayne18 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

Lincoln, IL (KILX), launched 00:00Z, 4.1 hours before the alert went out and 224 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, Lincoln, IL at 00:00Z on 2003-05-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2003-05-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 408 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
5 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
434 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
408 m²/s²
0-3 km storm-relative helicity
531 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 4, 7:34 PM CDTMesoscale DiscussionSPCAlexander116 min
May 4, 8:05 PM CDTMesoscale DiscussionSPCAdams, Bond, Brown, Bureau, Calhoun, Cass and 73 more85 min
May 4, 9:26 PM CDTMesoscale DiscussionSPCAlexander, Gallatin, Hardin, Johnson, Massac, Pope and 2 more2 hr
May 4, 10:40 PM CDTTornado WatchSPCEdwards, Franklin, Gallatin, Hamilton, Hardin, Jackson and 14 more5 hr
May 5, 1:20 AM CDTTornado WatchSPCAlexander, Massac, Pulaski6 hr
May 5, 1:30 AM CDTMesoscale DiscussionSPCEdwards, Franklin, Gallatin, Hamilton, Hardin, Jackson and 16 more90 min
May 5, 1:46 AM CDTMesoscale DiscussionSPCBond, Christian, Clark, Clay, Clinton, Coles and 25 more89 min
May 5, 3:41 AM CDTMesoscale DiscussionSPCAlexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more34 min
May 5, 3:50 AM CDTTornado WatchSPCAlexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 13 more6 hr
May 5, 6:32 AM CDTMesoscale DiscussionSPCAlexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 10 more88 min
May 5, 9:19 AM CDTMesoscale DiscussionSPCAlexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 13 more56 min
May 5, 12:20 PM CDTTornado WatchSPCHardin7 hr
May 4, 7:19 PM CDTMesoscale DiscussionSPCBarry, Barton, Cedar, Christian, Dade, Dallas and 18 more86 min
May 4, 9:05 PM CDTMesoscale DiscussionSPCBates, Benton, Boone, Caldwell, Carroll, Cass and 23 more85 min
May 4, 9:42 PM CDTMesoscale DiscussionSPCBarry, Barton, Camden, Carter, Cedar, Christian and 28 more93 min
May 5, 12:50 AM CDTTornado WatchSPCBarry, Carter, Cedar, Christian, Dade, Dallas and 21 more5 hr
May 5, 4:18 AM CDTMesoscale DiscussionSPCButler, Dunklin, Mississippi, New Madrid, Pemiscot, Ripley and 1 more57 min
May 5, 4:55 AM CDTTornado WatchSPCDunklin, Pemiscot6 hr
May 5, 1:05 PM CDTTornado WatchSPCDunklin3 hr
May 5, 2:35 PM CDTTornado WatchSPCNew Madrid, Pemiscot7 hr
May 5, 3:25 PM CDTTornado WatchSPCDunklin, Pemiscot7 hr
May 5, 5:18 PM CDTMesoscale DiscussionSPCDunklin, Pemiscot117 min

Nearby

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