Alert archive / Indiana / Mesoscale Discussions in 2011

Mesoscale Discussion 1787

July 29, 20118 counties in Illinois; 37 counties in Indiana; 5 counties in Ohio

The Storm Prediction Center issued this mesoscale discussion at Jul 29, 2011, 3:51 PM CDT for 8 counties in Illinois; 37 counties in Indiana; 5 counties in Ohio. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued: Jul 29, 2011, 3:51 PM CDT (20:51 UTC)
Expired: Jul 29, 2011, 5:15 PM CDT
In force: 84 min
Issued by: the Storm Prediction Center

All 50 counties

Champaign County, IL, Clark County, IL, Coles County, IL, Cumberland County, IL, Douglas County, IL, Edgar County, IL, Moultrie County, IL, Vermilion County, IL, Bartholomew County, IN, Blackford County, IN, Boone County, IN, Brown County, IN, Clay County, IN, Clinton County, IN, Decatur County, IN, Delaware County, IN, Fayette County, IN, Fountain County, IN, Franklin County, IN, Greene County, IN, Hamilton County, IN, Hancock County, IN, Hendricks County, IN, Henry County, IN, Jay County, IN, Johnson County, IN, Madison County, IN, Marion County, IN, Monroe County, IN, Montgomery County, IN, Morgan County, IN, Owen County, IN, Parke County, IN, Putnam County, IN, Randolph County, IN, Rush County, IN, Shelby County, IN, Sullivan County, IN, Tippecanoe County, IN, Tipton County, IN, Union County, IN, Vermillion County, IN, Vigo County, IN, Warren County, IN, Wayne County, IN, Butler County, OH, Darke County, OH, Miami County, OH, Montgomery County, OH, Preble County, OH

The radar

The Indianapolis radar (KIND), 34 km from the middle of the area, began a volume at 20:53 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, 8.9 hours before the alert went out and 172 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: 1383 J/kg
Mixed-layer CIN: -106 J/kg
Mixed-layer LCL: 1000 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 10 m²/s²
0-3 km storm-relative helicity: 29 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

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
Jul 28, 11:51 PM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Cook, DeKalb, DuPage, Kane and 9 more	84 min
Jul 29, 1:15 AM CDT	Severe Thunderstorm Watch	SPC	Elkhart, LaGrange, LaPorte, Saint Joseph, Steuben	6 hr
Jul 29, 2:31 AM CDT	Mesoscale Discussion	SPC	DeKalb, Elkhart, LaGrange, Steuben	89 min
Jul 29, 2:56 AM CDT	Severe Thunderstorm Watch	SPC	Ashtabula, Cuyahoga, Erie, Geauga, Lake, Lorain and 4 more	5 hr
Jul 29, 1:06 PM CDT	Mesoscale Discussion	SPC	Ashland, Belmont, Carroll, Champaign, Clark, Columbiana and 35 more	84 min

Nearby

Mesoscale Discussions in Indiana, 2011 Mesoscale Discussions in Illinois, 2011 Mesoscale Discussions in Ohio, 2011 Every mesoscale discussion in 2011

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.