Alert archive / Illinois / Mesoscale Discussions in 2017

Mesoscale Discussion 1755

November 5, 201736 counties in Illinois; 4 counties in Indiana; Jefferson County, Saint Louis County, City of Saint Louis, Missouri

The Storm Prediction Center issued this mesoscale discussion at Nov 5, 2017, 11:09 AM CST for 36 counties in Illinois; 4 counties in Indiana; Jefferson County, Saint Louis County, City of Saint Louis, Missouri. It was in force for 66 min.

The area

The outline as issued.

The facts

Issued: Nov 5, 2017, 11:09 AM CST (17:09 UTC)
Expired: Nov 5, 2017, 12:15 PM CST
In force: 66 min
Issued by: the Storm Prediction Center
Chance of a watch: 80%

All 43 counties

Bond County, IL, Champaign County, IL, Christian County, IL, Clark County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, Douglas 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, Jersey County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Montgomery County, IL, Moultrie County, IL, Perry County, IL, Piatt County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Shelby County, IL, Vermilion County, IL, Washington County, IL, Wayne County, IL, Fountain County, IN, Vermillion County, IN, Vigo County, IN, Warren County, IN, City of Saint Louis, MO, Jefferson County, MO, Saint Louis County, MO

The radar

The Lincoln radar (KILX), 111 km from the middle of the area, began a volume at 17:10 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.

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 5.2 hours before the alert went out and 92 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: 1199 J/kg
Mixed-layer CIN: -20 J/kg
Mixed-layer LCL: 454 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 322 m²/s²
0-3 km storm-relative helicity: 382 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 9.2

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
Nov 5, 6:04 AM CST	Mesoscale Discussion	SPC	Bond, Champaign, Christian, Clark, Coles, Cumberland and 19 more	2 hr
Nov 5, 12:35 PM CST	Tornado Watch	SPC	Bond, Champaign, Christian, Clark, Clay, Clinton and 24 more	6 hr
Nov 5, 2:51 PM CST	Mesoscale Discussion	SPC	Alexander, Bond, Christian, Clark, Clay, Clinton and 38 more	114 min
Nov 5, 3:50 PM CST	Tornado Watch	SPC	Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more	6 hr
Nov 5, 10:48 AM CST	Mesoscale Discussion	SPC	Bartholomew, Brown, Daviess, Dearborn, Decatur, Greene and 8 more	57 min
Nov 5, 11:08 AM CST	Tornado Watch	SPC	Adams, Bartholomew, Blackford, Boone, Brown, Carroll and 44 more	7 hr
Nov 5, 12:36 PM CST	Mesoscale Discussion	SPC	Boone, Carroll, Clinton, Grant, Hamilton, Howard and 4 more	54 min
Nov 5, 4:58 PM CST	Mesoscale Discussion	SPC	Bartholomew, Brown, Clark, Clay, Crawford, Dearborn and 28 more	62 min
Nov 5, 5:31 PM CST	Severe Thunderstorm Watch	SPC	Bartholomew, Brown, Clark, Crawford, Daviess, Dearborn and 20 more	6 hr

Nearby

Mesoscale Discussions in Illinois, 2017 Mesoscale Discussions in Indiana, 2017 Mesoscale Discussions in Missouri, 2017 Every mesoscale discussion in 2017

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.