Alert archive / Illinois / Mesoscale Discussions in 2015

Mesoscale Discussion 1109

June 21, 201512 counties in Illinois; Posey County, Indiana; 8 counties in Kentucky

The Storm Prediction Center issued this mesoscale discussion at Jun 21, 2015, 7:08 PM CDT for 12 counties in Illinois; Posey County, Indiana; 8 counties in Kentucky. It was in force for 67 min.

The area

The outline as issued.

The facts

Issued: Jun 21, 2015, 7:08 PM CDT (00:08 UTC)
Expired: Jun 21, 2015, 8:15 PM CDT
In force: 67 min
Issued by: the Storm Prediction Center

All 21 counties

Franklin County, IL, Gallatin County, IL, Hamilton County, IL, Hardin County, IL, Jackson County, IL, Jefferson County, IL, Perry County, IL, Pope County, IL, Saline County, IL, Washington County, IL, White County, IL, Williamson County, IL, Posey County, IN, Crittenden County, KY, Daviess County, KY, Henderson County, KY, Hopkins County, KY, McLean County, KY, Muhlenberg County, KY, Union County, KY, Webster County, KY

The radar

The Paducah radar (KPAH), 79 km from the middle of the area, began a volume at 00:09 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

Nashville Metro, TN (KBNA), launched 00:00Z, 0.1 hours before the alert went out and 242 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: 1999 J/kg
Mixed-layer CIN: -8 J/kg
Mixed-layer LCL: 1370 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: 27 m²/s²
0-3 km storm-relative helicity: 37 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
Jun 22, 7:42 AM CDT	Mesoscale Discussion	SPC	Carroll, Jo Daviess, Stephenson, Whiteside	93 min
Jun 22, 8:08 AM CDT	Severe Thunderstorm Watch	SPC	Carroll, Jo Daviess, Stephenson	4 hr
Jun 22, 9:14 AM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Cook, DeKalb, DuPage, Grundy and 11 more	61 min
Jun 22, 9:39 AM CDT	Severe Thunderstorm Watch	SPC	Boone, Bureau, Cook, DeKalb, DuPage, Ford and 19 more	3 hr
Jun 22, 11:00 AM CDT	Mesoscale Discussion	SPC	Bureau, Cook, DeKalb, DuPage, Grundy, Henry and 11 more	2 hr
Jun 22, 1:22 PM CDT	Mesoscale Discussion	SPC	Adams, Brown, Bureau, Carroll, Cass, Fulton and 21 more	113 min
Jun 22, 3:56 PM CDT	Tornado Watch	SPC	Bureau, Carroll, Cass, Champaign, Coles, DeKalb and 34 more	9 hr
Jun 22, 6:08 PM CDT	Mesoscale Discussion	SPC	Bureau, DeWitt, Fulton, Grundy, Hancock, Henderson and 21 more	67 min
Jun 22, 2:09 PM CDT	Mesoscale Discussion	SPC	Adams, Allen, DeKalb, Elkhart, Fulton, Huntington and 7 more	96 min

Nearby

Mesoscale Discussions in Illinois, 2015 Mesoscale Discussions in Kentucky, 2015 Mesoscale Discussions in Indiana, 2015 Every mesoscale discussion in 2015

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.