Alert archive / Missouri / Severe Thunderstorm Watches in 2004

Severe Thunderstorm Watch 258

May 23, 200414 counties in Illinois; 17 counties in Missouri

The Storm Prediction Center issued this severe thunderstorm watch at May 23, 2004, 1:40 AM CDT for 14 counties in Illinois; 17 counties in Missouri. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued: May 23, 2004, 1:40 AM CDT (06:40 UTC)
Expired: May 23, 2004, 6:00 AM CDT
In force: 4 hr
Issued by: the Storm Prediction Center

All 31 counties

Adams County, IL, Brown County, IL, Cass County, IL, Fulton County, IL, Hancock County, IL, Logan County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Pike County, IL, Schuyler County, IL, Scott County, IL, Tazewell County, IL, Adair County, MO, Buchanan County, MO, Caldwell County, MO, Clark County, MO, Clinton County, MO, Daviess County, MO, Grundy County, MO, Knox County, MO, Lewis County, MO, Linn County, MO, Livingston County, MO, Macon County, MO, Marion County, MO, Schuyler County, MO, Scotland County, MO, Shelby County, MO, Sullivan County, MO

The radar

The St Louis radar (KLSX), 199 km from the middle of the area, began a volume at 06:41 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.

Issued	Product	Office	Counties	Lasted
May 23, 1:45 AM CDT	Severe Thunderstorm Warning	EAX	Grundy, Putnam, Sullivan	60 min
May 23, 2:56 AM CDT	Severe Thunderstorm Warning	LSX	Knox, Lewis, Shelby	64 min
May 23, 2:58 AM CDT	Severe Thunderstorm Warning	EAX	Macon	47 min
May 23, 3:21 AM CDT	Severe Thunderstorm Warning	DVN	Hancock	59 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

Topeka, KS (KTOP), launched 00:00Z, 6.7 hours before the alert went out and 305 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: 2741 J/kg
Mixed-layer CIN: -101 J/kg
Mixed-layer LCL: 1089 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 167 m²/s²
0-3 km storm-relative helicity: 264 m²/s²
Significant tornado parameter: 1.7
Supercell composite: 21.9

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 22, 8:58 PM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Carroll, DeKalb, DuPage, Grundy and 23 more	92 min
May 23, 12:24 AM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 32 more	66 min
May 23, 12:40 AM CDT	Severe Thunderstorm Watch	SPC	Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 27 more	5 hr
May 23, 1:21 AM CDT	Mesoscale Discussion	SPC	Adams, Brown, Calhoun, Cass, Greene, Jersey and 6 more	24 min
May 23, 4:30 AM CDT	Mesoscale Discussion	SPC	Adams, Boone, Brown, Bureau, Carroll, Cass and 44 more	60 min
May 23, 10:45 AM CDT	Tornado Watch	SPC	Clark, Clay, Coles, Crawford, Cumberland, Edgar and 19 more	5 hr
May 23, 12:25 PM CDT	Mesoscale Discussion	SPC	Adams, Brown, Bureau, Calhoun, Carroll, Cass and 31 more	95 min
May 23, 12:45 PM CDT	Mesoscale Discussion	SPC	Clark, Clay, Coles, Crawford, Cumberland, Edgar and 18 more	2 hr
May 23, 1:15 PM CDT	Tornado Watch	SPC	Adams, Brown, Calhoun, Cass, Fulton, Greene and 16 more	6 hr
May 23, 2:05 PM CDT	Tornado Watch	SPC	Boone, Bureau, Carroll, DeKalb, DuPage, Grundy and 18 more	8 hr
May 23, 2:53 PM CDT	Mesoscale Discussion	SPC	Iroquois, Vermilion	67 min
May 23, 3:50 PM CDT	Tornado Watch	SPC	Cook, DuPage, Iroquois, Kankakee, Vermilion, Will	6 hr
May 23, 4:35 PM CDT	Severe Thunderstorm Watch	SPC	Monroe	5 hr
May 23, 5:00 PM CDT	Mesoscale Discussion	SPC	Adams, Bond, Brown, Calhoun, Cass, Christian and 28 more	2 hr
May 23, 5:10 PM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Carroll, DeKalb, DuPage, Grundy and 17 more	95 min
May 23, 5:30 PM CDT	Tornado Watch	SPC	Bond, Calhoun, Christian, Clark, Clay, Clinton and 29 more	6 hr
May 23, 6:30 PM CDT	Mesoscale Discussion	SPC	Cook, DuPage, Iroquois, Kankakee, Vermilion, Will	2 hr
May 22, 7:11 PM CDT	Mesoscale Discussion	SPC	Atchison	94 min
May 22, 10:40 PM CDT	Tornado Watch	SPC	Andrew, Atchison, Buchanan, Daviess, DeKalb, Gentry and 8 more	5 hr
May 22, 11:33 PM CDT	Mesoscale Discussion	SPC	Andrew, Atchison, Buchanan, Daviess, DeKalb, Gentry and 7 more	87 min
May 23, 2:21 AM CDT	Mesoscale Discussion	SPC	Adair, Andrew, Buchanan, Caldwell, Clinton, Daviess and 11 more	54 min

Nearby

Severe Thunderstorm Watches in Missouri, 2004 Severe Thunderstorm Watches in Illinois, 2004 Every severe thunderstorm watch in 2004

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.