Alert archive / Missouri / Mesoscale Discussions in 2011

Mesoscale Discussion 514

April 22, 201120 counties in Illinois; 23 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Apr 22, 2011, 10:09 AM CDT for 20 counties in Illinois; 23 counties in Missouri. It was in force for 66 min.

The area

The outline as issued.

The facts

Issued
Apr 22, 2011, 10:09 AM CDT (15:09 UTC)
Expired
Apr 22, 2011, 11:15 AM CDT
In force
66 min
Issued by
the Storm Prediction Center
All 43 counties

Alexander County, IL, Bond County, IL, Calhoun County, IL, Clinton County, IL, Franklin County, IL, Greene County, IL, Hamilton County, IL, Jackson County, IL, Jefferson County, IL, Jersey County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Perry County, IL, Randolph County, IL, Saint Clair County, IL, Union County, IL, Washington County, IL, Wayne County, IL, Williamson County, IL, Bollinger County, MO, Cape Girardeau County, MO, City of Saint Louis, MO, Crawford County, MO, Dent County, MO, Franklin County, MO, Gasconade County, MO, Iron County, MO, Jefferson County, MO, Lincoln County, MO, Madison County, MO, Osage County, MO, Perry County, MO, Phelps County, MO, Reynolds County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Scott County, MO, Warren County, MO, Washington County, MO, Wayne County, MO

The radar

The St Louis radar (KLSX), 101 km from the middle of the area, began a volume at 15:08 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, 3.2 hours before the alert went out and 306 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-pSkew-T log-p diagram, Lincoln, IL at 12:00Z on 2011-04-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 12:00Z on 2011-04-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 585 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
845 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
585 m²/s²
0-3 km storm-relative helicity
683 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.

IssuedProductOfficeCountiesLasted
Apr 22, 1:14 PM CDTMesoscale DiscussionSPCCrawford, Edwards, Jasper, Lawrence, Richland, Wabash61 min
Apr 22, 1:31 PM CDTSevere Thunderstorm WatchSPCEdwards, Franklin, Gallatin, Hamilton, Jefferson, Saline and 4 more4 hr
Apr 22, 3:34 PM CDTTornado WatchSPCCalhoun, Greene, Jersey, Macoupin, Madison, Monroe and 2 more6 hr
Apr 22, 5:21 PM CDTMesoscale DiscussionSPCCalhoun, Greene, Jersey, Macoupin114 min
Apr 22, 5:27 PM CDTMesoscale DiscussionSPCClinton, Edwards, Franklin, Gallatin, Hamilton, Hardin and 18 more33 min
Apr 22, 5:49 PM CDTTornado WatchSPCAlexander, Bond, Clay, Clinton, Crawford, Edwards and 26 more7 hr
Apr 21, 11:27 PM CDTMesoscale DiscussionSPCBarton, Bates, Buchanan, Cass, Clay, Jackson and 3 more3 hr
Apr 22, 2:48 AM CDTSevere Thunderstorm WatchSPCAndrew, Bates, Buchanan, Cass, Clay, Clinton and 4 more4 hr
Apr 22, 5:18 AM CDTMesoscale DiscussionSPCBuchanan, Caldwell, Cass, Clay, Clinton, Jackson and 2 more87 min
Apr 22, 10:44 AM CDTMesoscale DiscussionSPCBarry, Bollinger, Carter, Christian, Crawford, Dent and 19 more61 min
Apr 22, 1:04 PM CDTMesoscale DiscussionSPCBarry, Barton, Benton, Callaway, Camden, Cedar and 40 more116 min
Apr 22, 1:23 PM CDTMesoscale DiscussionSPCMcDonald, Newton97 min

Nearby

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