Alert archive / Missouri / Mesoscale Discussions in 2012
Mesoscale Discussion 851
The Storm Prediction Center issued this mesoscale discussion at May 20, 2012, 1:33 PM CDT for 5 states. It was in force for 87 min.
The area
The outline as issued.
The facts
- Issued
- May 20, 2012, 1:33 PM CDT (18:33 UTC)
- Expired
- May 20, 2012, 3:00 PM CDT
- In force
- 87 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
All 92 counties
Clay County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Fulton County, AR, Greene County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Lawrence County, AR, Mississippi County, AR, Poinsett County, AR, Randolph County, AR, Sharp County, AR, White County, AR, Woodruff County, AR, Alexander County, IL, Bond County, IL, Clinton County, IL, Franklin County, IL, Gallatin County, IL, Hamilton County, IL, Hardin County, IL, Jackson County, IL, Jefferson County, IL, Jersey County, IL, Johnson County, IL, Madison County, IL, Marion County, IL, Massac County, IL, Monroe County, IL, Perry County, IL, Pope County, IL, Pulaski County, IL, Randolph County, IL, Saint Clair County, IL, Saline County, IL, Union County, IL, Washington County, IL, Williamson County, IL, Ballard County, KY, Calloway County, KY, Carlisle County, KY, Crittenden County, KY, Fulton County, KY, Graves County, KY, Hickman County, KY, Livingston County, KY, Marshall County, KY, McCracken County, KY, Bollinger County, MO, Butler County, MO, Cape Girardeau County, MO, Carter County, MO, City of Saint Louis, MO, Crawford County, MO, Dent County, MO, Dunklin County, MO, Franklin County, MO, Howell County, MO, Iron County, MO, Jefferson County, MO, Madison County, MO, Mississippi County, MO, New Madrid County, MO, Oregon County, MO, Pemiscot County, MO, Perry County, MO, Phelps County, MO, Reynolds County, MO, Ripley County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Scott County, MO, Shannon County, MO, Stoddard County, MO, Texas County, MO, Washington County, MO, Wayne County, MO, Crockett County, TN, Dyer County, TN, Gibson County, TN, Haywood County, TN, Henry County, TN, Lake County, TN, Lauderdale County, TN, Obion County, TN, Shelby County, TN, Tipton County, TN, Weakley County, TN
The radar
The Paducah radar (KPAH), 143 km from the middle of the area, began a volume at 18:32 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
Little Rock, AR (KLZK), launched 12:00Z, 6.6 hours before the alert went out and 227 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.
- Mixed-layer CAPE
- 296 J/kg
- Mixed-layer CIN
- -82 J/kg
- Mixed-layer LCL
- 1577 m above ground
- 0-6 km bulk shear
- 6 kt
- 0-1 km storm-relative helicity
- -47 m²/s²
- 0-3 km storm-relative helicity
- -29 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 20, 1:17 PM CDT | Mesoscale Discussion | SPC | Boone, Brown, Bureau, Carroll, Cass, DeKalb and 32 more | 118 min |
| May 20, 3:50 PM CDT | Mesoscale Discussion | SPC | DeKalb, DuPage, Kane, McHenry | 85 min |
Nearby
Mesoscale Discussions in Missouri, 2012Mesoscale Discussions in Illinois, 2012Mesoscale Discussions in Arkansas, 2012Every mesoscale discussion in 2012
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.