Alert archive / Indiana / Mesoscale Discussions in 2011

Mesoscale Discussion 479

April 19, 20116 states

The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2011, 8:07 PM CDT for 6 states. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued
Apr 19, 2011, 8:07 PM CDT (01:07 UTC)
Expired
Apr 19, 2011, 9:30 PM CDT
In force
83 min
Issued by
the Storm Prediction Center
All 154 counties

Arkansas County, AR, Clay County, AR, Cleveland County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Dallas County, AR, Grant County, AR, Greene County, AR, Jackson County, AR, Jefferson County, AR, Lawrence County, AR, Lee County, AR, Lincoln County, AR, Lonoke County, AR, Mississippi County, AR, Monroe County, AR, Phillips County, AR, Poinsett County, AR, Prairie County, AR, Randolph County, AR, St. Francis County, AR, White County, AR, Woodruff County, AR, Alexander County, IL, Bond County, IL, Champaign 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, Gallatin County, IL, Hamilton County, IL, Hardin County, IL, Jackson County, IL, Jasper County, IL, Jefferson County, IL, Johnson County, IL, Lawrence County, IL, Madison County, IL, Marion County, IL, Massac County, IL, Monroe County, IL, Montgomery County, IL, Moultrie County, IL, Perry County, IL, Pope County, IL, Pulaski County, IL, Randolph County, IL, Richland County, IL, Saint Clair County, IL, Saline County, IL, Shelby County, IL, Union County, IL, Vermilion County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Blackford County, IN, Boone County, IN, Carroll County, IN, Cass County, IN, Clay County, IN, Clinton County, IN, Daviess County, IN, Delaware County, IN, Fountain County, IN, Fulton County, IN, Gibson County, IN, Grant County, IN, Greene County, IN, Hamilton County, IN, Hancock County, IN, Hendricks County, IN, Henry County, IN, Howard County, IN, Huntington County, IN, Johnson County, IN, Knox County, IN, Kosciusko County, IN, Madison County, IN, Marion County, IN, Miami County, IN, Monroe County, IN, Montgomery County, IN, Morgan County, IN, Owen County, IN, Parke County, IN, Pike County, IN, Posey County, IN, Pulaski County, IN, Putnam County, IN, Sullivan County, IN, Tippecanoe County, IN, Tipton County, IN, Vanderburgh County, IN, Vermillion County, IN, Vigo County, IN, Wabash County, IN, Warren County, IN, Wells County, IN, White County, IN, Whitley County, IN, Ballard County, KY, Carlisle County, KY, Crittenden County, KY, Fulton County, KY, Graves County, KY, Henderson County, KY, Hickman County, KY, Livingston County, KY, Marshall County, KY, McCracken County, KY, Union County, KY, Bollinger County, MO, Butler County, MO, Cape Girardeau County, MO, Carter County, MO, City of Saint Louis, MO, Dunklin County, MO, Howell County, MO, Iron County, MO, Jefferson County, MO, Madison County, MO, Mississippi County, MO, New Madrid County, MO, Oregon County, MO, Ozark County, MO, Pemiscot County, MO, Perry County, MO, Reynolds County, MO, Ripley County, MO, Saint Francois County, MO, Sainte Genevieve County, MO, Scott County, MO, Shannon County, MO, Stoddard County, MO, Washington County, MO, Wayne County, MO, Dyer County, TN, Lake County, TN, Lauderdale County, TN, Obion County, TN, Tipton County, TN

The radar

The Paducah radar (KPAH), 90 km from the middle of the area, began a volume at 01:08 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 00:00Z, 1.1 hours before the alert went out and 266 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 00:00Z on 2011-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2409 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2011-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 370 square meters per square second.19395878Sfc1 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
2409 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
523 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
370 m²/s²
0-3 km storm-relative helicity
547 m²/s²
Significant tornado parameter
0.0
Supercell composite
24.4

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 19, 7:47 PM CDTMesoscale DiscussionSPCConway, Franklin, Howard, Johnson, Little River, Logan and 13 more88 min
Apr 19, 10:14 PM CDTTornado WatchSPCAshley, Chicot7 hr
Apr 19, 11:17 PM CDTMesoscale DiscussionSPCColumbia, Hempstead, Lafayette, Little River, Miller, Nevada and 1 more58 min
Apr 19, 11:45 PM CDTSevere Thunderstorm WatchSPCColumbia, Hempstead, Lafayette, Little River, Miller, Nevada and 1 more3 hr
Apr 20, 3:37 AM CDTSevere Thunderstorm WatchSPCAshley, Chicot8 hr
Apr 20, 12:46 PM CDTMesoscale DiscussionSPCAshley, Bradley, Calhoun, Chicot, Columbia, Desha and 8 more89 min
Apr 20, 1:02 PM CDTSevere Thunderstorm WatchSPCAshley, Chicot, Lee, Phillips7 hr
Apr 20, 2:04 PM CDTSevere Thunderstorm WatchSPCArkansas, Bradley, Calhoun, Clark, Cleburne, Cleveland and 36 more7 hr
Apr 20, 5:24 PM CDTMesoscale DiscussionSPCChicot, Drew96 min
Apr 20, 5:56 PM CDTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Dallas and 23 more2 hr
Apr 19, 8:37 PM CDTSevere Thunderstorm WatchSPCAdams, Allen, Blackford, Cass, DeKalb, Elkhart and 18 more3 hr
Apr 19, 8:47 PM CDTMesoscale DiscussionSPCClark, Dearborn, Floyd, Jefferson, Ohio, Switzerland88 min
Apr 19, 9:13 PM CDTTornado WatchSPCClark, Crawford, Dearborn, Dubois, Fayette, Floyd and 12 more6 hr
Apr 19, 11:56 PM CDTMesoscale DiscussionSPCClark, Dearborn, Franklin, Jefferson, Ohio, Ripley and 1 more94 min
Apr 20, 12:59 AM CDTTornado WatchSPCBath, Bell, Boyd, Breathitt, Carter, Clay and 31 more5 hr
Apr 20, 2:20 AM CDTMesoscale DiscussionSPCBell, Boyd, Breathitt, Clay, Clinton, Cumberland and 23 more85 min
Apr 19, 9:39 PM CDTMesoscale DiscussionSPCBedford, Benton, Cannon, Carroll, Cheatham, Chester and 23 more66 min
Apr 20, 1:42 AM CDTTornado WatchSPCAnderson, Bledsoe, Blount, Bradley, Campbell, Cannon and 42 more5 hr

Nearby

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