Alert archive / Illinois / Mesoscale Discussions in 2014

Mesoscale Discussion 1712

September 10, 201425 counties in Illinois; 8 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Sep 10, 2014, 6:22 PM CDT for 25 counties in Illinois; 8 counties in Missouri. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued: Sep 10, 2014, 6:22 PM CDT (23:22 UTC)
Expired: Sep 10, 2014, 7:45 PM CDT
In force: 83 min
Issued by: the Storm Prediction Center

All 33 counties

Bond County, IL, Clark County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, Edgar County, IL, Edwards County, IL, Effingham County, IL, Fayette County, IL, Franklin County, IL, Hamilton County, IL, Jackson County, IL, Jasper County, IL, Jefferson County, IL, Lawrence County, IL, Marion County, IL, Monroe County, IL, Perry County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Washington County, IL, Wayne County, IL, City of Saint Louis, MO, Iron County, MO, Jefferson County, MO, Madison County, MO, Perry County, MO, Saint Francois County, MO, Sainte Genevieve County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 128 km from the middle of the area, began a volume at 23:22 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

Davenport, (KDVN), launched 12:00Z, 11.4 hours before the alert went out and 359 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: 68 J/kg
Mixed-layer CIN: -29 J/kg
Mixed-layer LCL: 478 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 103 m²/s²
0-3 km storm-relative helicity: 130 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 10, 5:02 AM CDT	Mesoscale Discussion	SPC	Adams, Brown, Cass, Hancock, McDonough, Menard and 4 more	118 min
Sep 10, 10:34 AM CDT	Mesoscale Discussion	SPC	Clark, Coles, Douglas, Edgar, Vermilion	116 min
Sep 10, 1:48 PM CDT	Mesoscale Discussion	SPC	Bond, Calhoun, Champaign, Christian, Clark, Clay and 31 more	117 min
Sep 10, 3:24 PM CDT	Severe Thunderstorm Watch	SPC	Bond, Calhoun, Champaign, Christian, Clark, Clay and 37 more	6 hr
Sep 10, 4:36 PM CDT	Mesoscale Discussion	SPC	Alexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 13 more	84 min
Sep 9, 9:00 PM CDT	Mesoscale Discussion	SPC	Andrew, Buchanan, Caldwell, Carroll, Clinton, Daviess and 7 more	90 min
Sep 9, 11:28 PM CDT	Mesoscale Discussion	SPC	Buchanan, Caldwell, Carroll, Chariton, Clay, Clinton and 4 more	32 min

Nearby

Mesoscale Discussions in Illinois, 2014 Mesoscale Discussions in Missouri, 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.