Alert archive / Illinois / Mesoscale Discussions in 2011

Mesoscale Discussion 335

April 3, 201110 counties in Illinois; 10 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Apr 3, 2011, 10:50 PM CDT for 10 counties in Illinois; 10 counties in Missouri. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued: Apr 3, 2011, 10:50 PM CDT (03:50 UTC)
Expired: Apr 4, 2011, 12:15 AM CDT
In force: 85 min
Issued by: the Storm Prediction Center

Counties Adams County, IL, Brown County, IL, Cass County, IL, Fulton County, IL, Hancock County, IL, Mason County, IL, McDonough County, IL, Peoria County, IL, Schuyler County, IL, Tazewell County, IL, Chariton County, MO, Howard County, MO, Knox County, MO, Lewis County, MO, Macon County, MO, Marion County, MO, Monroe County, MO, Ralls County, MO, Randolph County, MO, Shelby County, MO

The radar

The St Louis radar (KLSX), 141 km from the middle of the area, began a volume at 03:53 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

Davenport, (KDVN), launched 00:00Z, 3.8 hours before the alert went out and 216 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: 1790 J/kg
Mixed-layer CIN: -85 J/kg
Mixed-layer LCL: 1684 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 119 m²/s²
0-3 km storm-relative helicity: 168 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 5.9

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
Apr 3, 7:44 PM CDT	Mesoscale Discussion	SPC	Boone, Bureau, Carroll, Fulton, Hancock, Henderson and 16 more	61 min
Apr 3, 8:11 PM CDT	Severe Thunderstorm Watch	SPC	Adams, Brown, Calhoun, Cass, Fulton, Greene and 12 more	6 hr
Apr 3, 8:54 PM CDT	Severe Thunderstorm Watch	SPC	Boone, Cook, DeKalb, DuPage, Grundy, Kane and 9 more	5 hr
Apr 3, 10:23 PM CDT	Mesoscale Discussion	SPC	Boone, Carroll, Cook, DeKalb, DuPage, Jo Daviess and 10 more	67 min
Apr 4, 1:29 AM CDT	Mesoscale Discussion	SPC	Adams, Bond, Brown, Calhoun, Cass, Christian and 31 more	91 min
Apr 4, 1:53 AM CDT	Mesoscale Discussion	SPC	Cook, DuPage, Grundy, Kane, Kendall, Lake and 2 more	97 min
Apr 4, 4:20 AM CDT	Mesoscale Discussion	SPC	Clark, Clay, Crawford, Effingham, Jasper, Lawrence and 2 more	25 min
Apr 4, 6:53 AM CDT	Mesoscale Discussion	SPC	Hardin, Lawrence, Wabash	2 hr
Apr 4, 7:22 AM CDT	Tornado Watch	SPC	Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more	7 hr
Apr 3, 7:26 PM CDT	Mesoscale Discussion	SPC	Adair, Andrew, Buchanan, Caldwell, Carroll, Chariton and 16 more	64 min
Apr 3, 8:15 PM CDT	Mesoscale Discussion	SPC	Adair, Andrew, Barton, Bates, Buchanan, Caldwell and 22 more	60 min
Apr 3, 8:33 PM CDT	Severe Thunderstorm Watch	SPC	Barton, Benton, Camden, Cedar, Dade, Hickory and 5 more	5 hr
Apr 3, 9:51 PM CDT	Mesoscale Discussion	SPC	Barry, McDonald, Newton	84 min
Apr 3, 11:02 PM CDT	Mesoscale Discussion	SPC	Barton, Camden, Cedar, Dade, Dallas, Greene and 10 more	88 min
Apr 4, 5:48 AM CDT	Mesoscale Discussion	SPC	Oregon, Ripley	117 min

Nearby

Mesoscale Discussions in Illinois, 2011 Mesoscale Discussions in Missouri, 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.