Alert archive / Illinois / Mesoscale Discussions in 2018

Mesoscale Discussion 1095

July 19, 201819 counties in Illinois; Gibson County, Posey County, Indiana

The Storm Prediction Center issued this mesoscale discussion at Jul 19, 2018, 11:43 PM CDT for 19 counties in Illinois; Gibson County, Posey County, Indiana. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued: Jul 19, 2018, 11:43 PM CDT (04:43 UTC)
Expired: Jul 20, 2018, 1:15 AM CDT
In force: 92 min
Issued by: the Storm Prediction Center

All 21 counties

Bond County, IL, Clay County, IL, Clinton County, IL, Cumberland County, IL, Edwards County, IL, Effingham County, IL, Fayette County, IL, Franklin County, IL, Hamilton County, IL, Jasper County, IL, Jefferson County, IL, Marion County, IL, Montgomery County, IL, Richland County, IL, Shelby County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Gibson County, IN, Posey County, IN

The radar

The Evansville,IN radar (KVWX), 100 km from the middle of the area, began a volume at 04:46 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 00:00Z, 4.7 hours before the alert went out and 162 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: 939 J/kg
Mixed-layer CIN: -83 J/kg
Mixed-layer LCL: 1091 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 107 m²/s²
0-3 km storm-relative helicity: 203 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 3.9

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 19, 9:36 PM CDT	Mesoscale Discussion	SPC	Adams, Bond, Brown, Calhoun, Cass, Christian and 23 more	54 min
Jul 20, 12:58 PM CDT	Mesoscale Discussion	SPC	Alexander, Gallatin, Hardin, Johnson, Massac, Pope and 4 more	62 min
Jul 20, 6:22 PM CDT	Tornado Watch	SPC	Alexander, Gallatin, Hardin, Johnson, Massac, Pope and 5 more	8 hr
Jul 20, 12:19 PM CDT	Mesoscale Discussion	SPC	Bartholomew, Clark, Crawford, Dearborn, Decatur, Fayette and 15 more	56 min
Jul 20, 12:37 PM CDT	Tornado Watch	SPC	Bartholomew, Clark, Crawford, Dearborn, Decatur, Dubois and 18 more	7 hr
Jul 20, 12:43 PM CDT	Mesoscale Discussion	SPC	Adams, Allen, Blackford, Carroll, Cass, DeKalb and 16 more	92 min
Jul 20, 1:12 PM CDT	Tornado Watch	SPC	Adams, Allen, Blackford, DeKalb, Elkhart, Grant and 10 more	3 hr
Jul 20, 2:43 PM CDT	Mesoscale Discussion	SPC	Clark, Crawford, Dearborn, Decatur, Floyd, Franklin and 10 more	62 min
Jul 20, 2:59 PM CDT	Mesoscale Discussion	SPC	Adams, Allen, Blackford, DeKalb, Delaware, Jay and 2 more	61 min
Jul 20, 5:37 PM CDT	Mesoscale Discussion	SPC	Bartholomew, Brown, Clark, Crawford, Dearborn, Decatur and 22 more	53 min

Nearby

Mesoscale Discussions in Illinois, 2018 Mesoscale Discussions in Indiana, 2018 Every mesoscale discussion in 2018

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.