Alert archive / Indiana / Mesoscale Discussions in 2020

Mesoscale Discussion 303

April 7, 20209 counties in Illinois; 20 counties in Indiana

The Storm Prediction Center issued this mesoscale discussion at Apr 7, 2020, 11:20 PM CDT for 9 counties in Illinois; 20 counties in Indiana. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued: Apr 7, 2020, 11:20 PM CDT (04:20 UTC)
Expired: Apr 8, 2020, 12:45 AM CDT
In force: 85 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 29 counties

Champaign County, IL, Christian County, IL, Coles County, IL, Douglas County, IL, Edgar County, IL, Macon County, IL, Moultrie County, IL, Piatt County, IL, Vermilion County, IL, Benton County, IN, Boone County, IN, Carroll County, IN, Cass County, IN, Clinton County, IN, Delaware County, IN, Fountain County, IN, Hamilton County, IN, Hendricks County, IN, Howard County, IN, Madison County, IN, Marion County, IN, Montgomery County, IN, Parke County, IN, Putnam County, IN, Tippecanoe County, IN, Tipton County, IN, Vermillion County, IN, Warren County, IN, White County, IN

The radar

The Indianapolis radar (KIND), 110 km from the middle of the area, began a volume at 04:24 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, 4.3 hours before the alert went out and 97 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: 1131 J/kg
Mixed-layer CIN: -137 J/kg
Mixed-layer LCL: 1546 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 121 m²/s²
0-3 km storm-relative helicity: 217 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 3.7

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
Apr 7, 7:22 PM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 18 more	83 min
Apr 8, 1:46 PM CDT	Mesoscale Discussion	SPC	Adams, Bond, Brown, Calhoun, Cass, Champaign and 43 more	119 min
Apr 8, 3:08 PM CDT	Severe Thunderstorm Watch	SPC	Adams, Bond, Brown, Bureau, Calhoun, Cass and 58 more	6 hr
Apr 8, 3:45 PM CDT	Mesoscale Discussion	SPC	Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 14 more	2 hr
Apr 8, 4:24 PM CDT	Tornado Watch	SPC	Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 14 more	7 hr
Apr 7, 8:07 PM CDT	Severe Thunderstorm Watch	SPC	Adams, Allen, Blackford, Cass, DeKalb, Elkhart and 18 more	6 hr
Apr 7, 9:04 PM CDT	Mesoscale Discussion	SPC	Adams, Allen, DeKalb, Fulton, Huntington, Kosciusko and 6 more	86 min
Apr 8, 5:52 PM CDT	Mesoscale Discussion	SPC	Bartholomew, Boone, Brown, Clark, Clay, Clinton and 52 more	2 hr
Apr 8, 6:24 PM CDT	Tornado Watch	SPC	Bartholomew, Boone, Brown, Carroll, Clark, Clay and 51 more	5 hr

Nearby

Mesoscale Discussions in Indiana, 2020 Mesoscale Discussions in Illinois, 2020 Every mesoscale discussion in 2020

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.