Alert archive / Illinois / Mesoscale Discussions in 2005

Mesoscale Discussion 814

May 11, 20058 counties in Illinois; 7 counties in Iowa

The Storm Prediction Center issued this mesoscale discussion at May 11, 2005, 3:11 AM CDT for 8 counties in Illinois; 7 counties in Iowa. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: May 11, 2005, 3:11 AM CDT (08:11 UTC)
Expired: May 11, 2005, 5:15 AM CDT
In force: 2 hr
Issued by: the Storm Prediction Center

Counties Cedar County, IA, Clinton County, IA, Johnson County, IA, Louisa County, IA, Muscatine County, IA, Scott County, IA, Washington County, IA, Bureau County, IL, Henry County, IL, Lee County, IL, Marshall County, IL, Mercer County, IL, Rock Island County, IL, Stark County, IL, Whiteside County, IL

The radar

The Quad Cities radar (KDVN), 9 km from the middle of the area, began a volume at 08:10 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.

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 8.2 hours before the alert went out and 14 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: 422 J/kg
Mixed-layer CIN: -85 J/kg
Mixed-layer LCL: 2014 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: -6 m²/s²
0-3 km storm-relative helicity: 132 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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 11, 8:41 AM CDT	Mesoscale Discussion	SPC	Adams, Hancock	2 hr
May 11, 1:37 PM CDT	Mesoscale Discussion	SPC	Adams, Brown, Calhoun, Cass, Christian, Coles and 22 more	113 min
May 11, 1:55 PM CDT	Severe Thunderstorm Watch	SPC	Adams, Brown, Calhoun, Cass, Fulton, Greene and 11 more	6 hr
May 11, 3:21 PM CDT	Mesoscale Discussion	SPC	Champaign, Clark, Coles, Cumberland, DeWitt, Douglas and 4 more	114 min
May 11, 6:28 PM CDT	Mesoscale Discussion	SPC	Christian, Clark, Clay, Coles, Crawford, Cumberland and 13 more	2 hr
May 10, 7:30 PM CDT	Mesoscale Discussion	SPC	Benton, Black Hawk, Boone, Bremer, Buchanan, Butler and 26 more	2 hr
May 10, 9:14 PM CDT	Mesoscale Discussion	SPC	Audubon, Black Hawk, Boone, Bremer, Buena Vista, Butler and 33 more	2 hr
May 10, 9:54 PM CDT	Mesoscale Discussion	SPC	Allamakee, Cerro Gordo, Chickasaw, Clay, Clayton, Dickinson and 15 more	2 hr
May 10, 11:35 PM CDT	Mesoscale Discussion	SPC	Adair, Audubon, Benton, Black Hawk, Boone, Bremer and 35 more	85 min

Nearby

Mesoscale Discussions in Illinois, 2005 Mesoscale Discussions in Iowa, 2005 Every mesoscale discussion in 2005

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.