Alert archive / Illinois / Mesoscale Discussions in 2007

Mesoscale Discussion 1807

August 19, 200737 counties in Illinois; 10 counties in Indiana; 5 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Aug 19, 2007, 6:25 PM CDT for 37 counties in Illinois; 10 counties in Indiana; 5 counties in Missouri. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Aug 19, 2007, 6:25 PM CDT (23:25 UTC)
Expired: Aug 19, 2007, 8:30 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 52 counties

Bond County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Champaign County, IL, Christian County, IL, Clark County, IL, Coles County, IL, Cumberland County, IL, DeWitt County, IL, Douglas County, IL, Edgar County, IL, Fayette County, IL, Ford County, IL, Greene County, IL, Iroquois County, IL, Jersey County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Mason County, IL, McLean County, IL, Menard County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Piatt County, IL, Pike County, IL, Saint Clair County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Tazewell County, IL, Vermilion County, IL, Benton County, IN, Clinton County, IN, Fountain County, IN, Montgomery County, IN, Parke County, IN, Tippecanoe County, IN, Vermillion County, IN, Vigo County, IN, Warren County, IN, White County, IN, City of Saint Louis, MO, Lincoln County, MO, Pike County, MO, Saint Charles County, MO, Saint Louis County, MO

The radar

The Lincoln radar (KILX), 47 km from the middle of the area, began a volume at 23:26 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

Lincoln, IL (KILX), launched 12:00Z, 11.4 hours before the alert went out and 71 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: 1072 J/kg
Mixed-layer CIN: -90 J/kg
Mixed-layer LCL: 1097 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 79 m²/s²
0-3 km storm-relative helicity: 61 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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
Aug 19, 6:12 AM CDT	Mesoscale Discussion	SPC	Boone, Carroll, DeKalb, Jo Daviess, Kane, Ogle and 2 more	93 min
Aug 19, 1:20 PM CDT	Mesoscale Discussion	SPC	DeKalb, Henderson, Henry, Jo Daviess, Kendall, Knox and 9 more	3 hr
Aug 19, 1:58 PM CDT	Mesoscale Discussion	SPC	Barry, Barton, Bates, Benton, Camden, Cedar and 31 more	3 hr

Nearby

Mesoscale Discussions in Illinois, 2007 Mesoscale Discussions in Indiana, 2007 Mesoscale Discussions in Missouri, 2007 Every mesoscale discussion in 2007

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.