Alert archive / Illinois / Mesoscale Discussions in 2004

Mesoscale Discussion 850

May 23, 200423 counties in Illinois; 4 counties in Iowa; 19 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at May 23, 2004, 5:10 PM CDT for 23 counties in Illinois; 4 counties in Iowa; 19 counties in Wisconsin. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued: May 23, 2004, 5:10 PM CDT (22:10 UTC)
Expired: May 23, 2004, 6:45 PM CDT
In force: 95 min
Issued by: the Storm Prediction Center

All 46 counties

Clinton County, IA, Dubuque County, IA, Jackson County, IA, Scott County, IA, Boone County, IL, Bureau County, IL, Carroll County, IL, DeKalb County, IL, DuPage County, IL, Grundy County, IL, Henry County, IL, Jo Daviess County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Lake County, IL, LaSalle County, IL, Lee County, IL, McHenry County, IL, Mercer County, IL, Ogle County, IL, Putnam County, IL, Rock Island County, IL, Stephenson County, IL, Whiteside County, IL, Will County, IL, Winnebago County, IL, Columbia County, WI, Crawford County, WI, Dane County, WI, Dodge County, WI, Grant County, WI, Green County, WI, Iowa County, WI, Jefferson County, WI, Kenosha County, WI, Lafayette County, WI, Milwaukee County, WI, Ozaukee County, WI, Racine County, WI, Richland County, WI, Rock County, WI, Sauk County, WI, Walworth County, WI, Washington County, WI, Waukesha County, WI

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 10.2 hours before the alert went out and 256 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: 435 J/kg
Mixed-layer CIN: -95 J/kg
Mixed-layer LCL: 621 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 18 m²/s²
0-3 km storm-relative helicity: 59 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

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.

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, 1:40 AM CDT	Severe Thunderstorm Watch	SPC	Adams, Brown, Cass, Fulton, Hancock, Logan and 8 more	4 hr
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, 5:30 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	Adair, Adams, Audubon, Cass, Clarke, Dallas and 15 more	94 min
May 22, 7:23 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Audubon, Cass, Dallas, Fremont and 9 more	67 min
May 22, 10:40 PM CDT	Tornado Watch	SPC	Adair, Adams, Appanoose, Benton, Cedar, Clarke and 33 more	5 hr
May 22, 11:33 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Benton, Cedar, Clarke and 33 more	87 min
May 23, 2:21 AM CDT	Mesoscale Discussion	SPC	Appanoose, Buchanan, Cedar, Davis, Delaware, Des Moines and 14 more	54 min

Nearby

Mesoscale Discussions in Illinois, 2004 Mesoscale Discussions in Wisconsin, 2004 Mesoscale Discussions in Iowa, 2004 Every mesoscale discussion 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.