Alert archive / Illinois / Severe Thunderstorm Watches in 2003

Severe Thunderstorm Watch 235

May 4, 200341 counties in Illinois; 5 counties in Iowa; 34 counties in Missouri

The Storm Prediction Center issued this severe thunderstorm watch at May 4, 2003, 5:25 PM CDT for 41 counties in Illinois; 5 counties in Iowa; 34 counties in Missouri. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: May 4, 2003, 5:25 PM CDT (22:25 UTC)
Expired: May 4, 2003, 11:00 PM CDT
In force: 6 hr
Issued by: the Storm Prediction Center

All 80 counties

Appanoose County, IA, Davis County, IA, Des Moines County, IA, Lee County, IA, Van Buren County, IA, Adams County, IL, Bond County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Christian County, IL, Clinton County, IL, Fayette County, IL, Franklin County, IL, Fulton County, IL, Greene County, IL, Hancock County, IL, Henderson County, IL, Jackson County, IL, Jefferson County, IL, Jersey County, IL, Johnson County, IL, Knox County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Mason County, IL, McDonough County, IL, Menard County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Peoria County, IL, Perry County, IL, Pike County, IL, Pope County, IL, Randolph County, IL, Saint Clair County, IL, Saline County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Union County, IL, Warren County, IL, Washington County, IL, Williamson County, IL, Adair County, MO, Audrain County, MO, Bollinger County, MO, Callaway County, MO, Cape Girardeau County, MO, City of Saint Louis, MO, Clark County, MO, Crawford County, MO, Dent County, MO, Franklin County, MO, Gasconade County, MO, Iron County, MO, Jefferson County, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Madison County, MO, Marion County, MO, Monroe County, MO, Montgomery County, MO, Osage County, MO, Perry County, MO, Pike County, MO, Ralls County, MO, Reynolds County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Schuyler County, MO, Scotland County, MO, Shelby County, MO, Warren County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 88 km from the middle of the area, began a volume at 22:27 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

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

Issued	Product	Office	Counties	Lasted
May 4, 5:34 PM CDT	Severe Thunderstorm Warning	ILX	Cass, Christian, Menard, Morgan, Sangamon, Scott	56 min
May 4, 5:40 PM CDT	Severe Thunderstorm Warning	LSX	Pike	50 min
May 4, 5:47 PM CDT	Severe Thunderstorm Warning	ILX	Fulton, Mason	43 min
May 4, 5:48 PM CDT	Severe Thunderstorm Warning	ILX	Schuyler	42 min
May 4, 6:01 PM CDT	Severe Thunderstorm Warning	LSX	Pike	44 min
May 4, 6:52 PM CDT	Severe Thunderstorm Warning	DVN	Henderson, Warren	38 min
May 4, 8:04 PM CDT	Severe Thunderstorm Warning	PAH	Jefferson	26 min
May 4, 9:14 PM CDT	Severe Thunderstorm Warning	LSX	Gasconade	31 min
May 4, 9:36 PM CDT	Flash Flood Warning	PAH	Johnson	3 hr
May 4, 9:47 PM CDT	Flash Flood Warning	PAH	Alexander, Massac, Pope, Pulaski	3 hr
May 4, 9:58 PM CDT	Tornado Warning	PAH	Pope	47 min
May 4, 10:17 PM CDT	Tornado Warning	SGF	Dent	58 min
May 4, 10:40 PM CDT	Tornado Warning	LSX	Crawford	50 min
May 4, 10:57 PM CDT	Severe Thunderstorm Warning	DVN	Clark, Scotland	48 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 12:00Z, 10.4 hours before the alert went out and 174 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1363 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: -4 m²/s²
0-3 km storm-relative helicity: 162 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.

Issued	Product	Office	Counties	Lasted
May 4, 4:50 AM CDT	Severe Thunderstorm Watch	SPC	Adams, Calhoun, Hancock, Monroe, Pike	6 hr
May 4, 6:55 PM CDT	Tornado Watch	SPC	Alexander	6 hr
May 3, 11:46 PM CDT	Mesoscale Discussion	SPC	Adams, Cass, Fremont, Harrison, Mills, Monona and 5 more	59 min
May 4, 12:10 AM CDT	Severe Thunderstorm Watch	SPC	Adair, Adams, Audubon, Boone, Carroll, Cass and 18 more	6 hr
May 4, 2:58 AM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Audubon, Boone, Carroll and 37 more	92 min
May 4, 7:43 AM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Cass, Clarke, Davis and 15 more	2 hr
May 4, 9:48 AM CDT	Mesoscale Discussion	SPC	Audubon, Buena Vista, Carroll, Cass, Cherokee, Clay and 17 more	117 min
May 4, 12:14 PM CDT	Mesoscale Discussion	SPC	Fremont, Mills, Montgomery, Page, Pottawattamie, Taylor	2 hr
May 4, 12:45 PM CDT	Tornado Watch	SPC	Adams, Cass, Fremont, Mills, Montgomery, Page and 2 more	6 hr
May 4, 2:22 PM CDT	Mesoscale Discussion	SPC	Fremont, Mills, Montgomery, Page, Pottawattamie, Taylor	113 min
May 4, 3:56 PM CDT	Mesoscale Discussion	SPC	Adair, Appanoose, Audubon, Boone, Carroll, Cass and 22 more	2 hr
May 4, 5:50 PM CDT	Severe Thunderstorm Watch	SPC	Adair, Adams, Appanoose, Clarke, Dallas, Decatur and 14 more	5 hr
May 4, 12:35 PM CDT	Tornado Watch	SPC	Barry, Barton, Cedar, Dade, Jasper, Lawrence and 4 more	6 hr
May 4, 3:05 PM CDT	Mesoscale Discussion	SPC	Barton, Jasper, McDonald, Newton	115 min
May 4, 4:28 PM CDT	Mesoscale Discussion	SPC	Buchanan, Caldwell, Clay, Clinton, DeKalb, Jackson and 3 more	62 min
May 4, 4:43 PM CDT	Mesoscale Discussion	SPC	Barton, Bates, Cedar, Dade, Jasper, Newton and 2 more	2 hr
May 4, 5:01 PM CDT	Mesoscale Discussion	SPC	Butler, Dunklin, Mississippi, New Madrid, Pemiscot, Stoddard	3 hr
May 4, 5:20 PM CDT	Mesoscale Discussion	SPC	Barry, Barton, Cedar, Christian, Dade, Dallas and 18 more	55 min
May 4, 6:05 PM CDT	Tornado Watch	SPC	Barry, Barton, Camden, Carter, Cedar, Christian and 30 more	7 hr
May 4, 6:20 PM CDT	Tornado Watch	SPC	Andrew, Bates, Benton, Boone, Buchanan, Caldwell and 34 more	6 hr

Nearby

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