Alert archive / Indiana / Mesoscale Discussions in 2014

Mesoscale Discussion 1741

September 20, 20144 states

The Storm Prediction Center issued this mesoscale discussion at Sep 20, 2014, 4:22 PM CDT for 4 states. It was in force for 113 min.

The area

The outline as issued.

The facts

Issued: Sep 20, 2014, 4:22 PM CDT (21:22 UTC)
Expired: Sep 20, 2014, 6:15 PM CDT
In force: 113 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 53 counties

Champaign County, IL, Christian County, IL, Clark County, IL, Coles County, IL, Cumberland County, IL, Douglas County, IL, Edgar County, IL, Greene County, IL, Macon County, IL, Macoupin County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Piatt County, IL, Sangamon County, IL, Scott County, IL, Shelby County, IL, Vermilion County, IL, Adams County, IN, Blackford County, IN, Boone County, IN, Clay County, IN, Clinton County, IN, Delaware County, IN, Fountain County, IN, Grant County, IN, Hamilton County, IN, Hancock County, IN, Hendricks County, IN, Henry County, IN, Howard County, IN, Jay County, IN, Madison County, IN, Marion County, IN, Montgomery County, IN, Parke County, IN, Putnam County, IN, Randolph County, IN, Tipton County, IN, Vermillion County, IN, Vigo County, IN, Wells County, IN, Hillsdale County, MI, Lenawee County, MI, Allen County, OH, Defiance County, OH, Fulton County, OH, Henry County, OH, Mercer County, OH, Paulding County, OH, Putnam County, OH, Van Wert County, OH, Williams County, OH

The radar

The Indianapolis radar (KIND), 95 km from the middle of the area, began a volume at 21:23 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 505Sep 20, 5:20 PM CDT

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.4 hours before the alert went out and 154 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: 46 J/kg
Mixed-layer CIN: -295 J/kg
Mixed-layer LCL: 792 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 107 m²/s²
0-3 km storm-relative helicity: 93 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
Sep 20, 1:25 PM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Cass, Cook, DeKalb, DeWitt and 33 more	95 min
Sep 20, 2:12 PM CDT	Severe Thunderstorm Watch	SPC	Bureau, Cass, DeWitt, Ford, Fulton, Grundy and 24 more	5 hr
Sep 20, 5:19 PM CDT	Mesoscale Discussion	SPC	Ford, Iroquois	56 min
Sep 20, 6:56 PM CDT	Mesoscale Discussion	SPC	Adams, Brown, Bureau, Cass, DeWitt, Fulton and 26 more	2 hr
Sep 20, 5:00 PM CDT	Mesoscale Discussion	SPC	Genesee, Ingham, Lapeer, Livingston, Oakland, Saint Clair and 3 more	2 hr
Sep 20, 5:19 PM CDT	Severe Thunderstorm Watch	SPC	Genesee, Huron, Lapeer, Lenawee, Livingston, Macomb and 8 more	4 hr

Nearby

Mesoscale Discussions in Indiana, 2014 Mesoscale Discussions in Illinois, 2014 Mesoscale Discussions in Ohio, 2014 Every mesoscale discussion in 2014

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.