Alert archive / Illinois / Mesoscale Discussions in 2015

Mesoscale Discussion 231

April 8, 20154 states

The Storm Prediction Center issued this mesoscale discussion at Apr 8, 2015, 12:50 PM CDT for 4 states. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued
Apr 8, 2015, 12:50 PM CDT (17:50 UTC)
Expired
Apr 8, 2015, 2:15 PM CDT
In force
85 min
Issued by
the Storm Prediction Center
Chance of a watch
80%
All 70 counties

Bond County, IL, Calhoun 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, DeWitt County, IL, Douglas County, IL, Edgar County, IL, Edwards County, IL, Effingham County, IL, Fayette County, IL, Greene County, IL, Jasper County, IL, Jefferson County, IL, Jersey County, IL, Lawrence County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Piatt County, IL, Richland County, IL, Saint Clair County, IL, Sangamon County, IL, Shelby County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, Clark County, IN, Clay County, IN, Crawford County, IN, Daviess County, IN, Dubois County, IN, Floyd County, IN, Gibson County, IN, Greene County, IN, Harrison County, IN, Knox County, IN, Lawrence County, IN, Martin County, IN, Orange County, IN, Owen County, IN, Pike County, IN, Scott County, IN, Sullivan County, IN, Vigo County, IN, Warrick County, IN, Washington County, IN, Jefferson County, KY, Oldham County, KY, City of Saint Louis, MO, Franklin County, MO, Gasconade County, MO, Jefferson County, MO, Lincoln County, MO, Montgomery County, MO, Osage County, MO, Saint Charles County, MO, Saint Louis County, MO, Warren County, MO

The radar

The Evansville,IN radar (KVWX), 117 km from the middle of the area, began a volume at 17:50 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, 5.8 hours before the alert went out and 149 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 2015-04-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 195 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 12:00Z on 2015-04-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 66 square meters per square second.193958Sfc1 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
195 J/kg
Mixed-layer CIN
-238 J/kg
Mixed-layer LCL
839 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
66 m²/s²
0-3 km storm-relative helicity
142 m²/s²
Significant tornado parameter
0.0
Supercell composite
7.7

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 8, 7:41 AM CDTMesoscale DiscussionSPCClark, Coles, Cumberland64 min
Apr 8, 12:01 PM CDTMesoscale DiscussionSPCJackson, Monroe, Perry, Randolph, Saint Clair, Washington59 min
Apr 8, 1:05 PM CDTSevere Thunderstorm WatchSPCBond, Calhoun, Champaign, Christian, Clark, Clay and 42 more5 hr
Apr 8, 2:43 PM CDTMesoscale DiscussionSPCBond, Brown, Calhoun, Cass, Champaign, Christian and 45 more92 min
Apr 8, 3:42 PM CDTMesoscale DiscussionSPCFranklin, Gallatin, Hamilton, Jackson, Jefferson, Monroe and 7 more63 min
Apr 8, 4:07 PM CDTTornado WatchSPCEdwards, Franklin, Gallatin, Hamilton, Hardin, Jackson and 13 more4 hr
Apr 8, 9:16 AM CDTMesoscale DiscussionSPCClark, Dearborn, Jefferson, Jennings, Ohio, Ripley and 2 more119 min
Apr 8, 9:34 AM CDTSevere Thunderstorm WatchSPCDearborn, Franklin, Jefferson, Ohio, Ripley, Switzerland5 hr
Apr 7, 7:58 PM CDTMesoscale DiscussionSPCBell, Breathitt, Clay, Floyd, Harlan, Jackson and 14 more62 min
Apr 8, 10:52 AM CDTMesoscale DiscussionSPCBath, Bourbon, Boyd, Bracken, Carter, Elliott and 17 more83 min
Apr 8, 11:33 AM CDTSevere Thunderstorm WatchSPCFloyd, Johnson, Lawrence, Magoffin, Martin, Menifee and 5 more5 hr
Apr 8, 12:51 PM CDTMesoscale DiscussionSPCBoyd, Breathitt, Carter, Elliott, Floyd, Greenup and 10 more84 min
Apr 8, 1:55 PM CDTMesoscale DiscussionSPCAdair, Allen, Anderson, Barren, Boyle, Breckinridge and 54 more2 hr
Apr 8, 2:22 PM CDTMesoscale DiscussionSPCBoyd, Breathitt, Clay, Elliott, Floyd, Johnson and 12 more83 min
Apr 8, 4:50 PM CDTMesoscale DiscussionSPCAdair, Anderson, Barren, Bath, Bourbon, Boyle and 50 more115 min
Apr 7, 8:24 PM CDTSevere Thunderstorm WatchSPCBarton, Bates, Benton, Cass, Cedar, Cooper and 13 more5 hr
Apr 7, 10:13 PM CDTMesoscale DiscussionSPCBarton, Bates, Benton, Cass, Cedar, Henry and 6 more2 hr
Apr 8, 6:17 AM CDTMesoscale DiscussionSPCBates, Benton, Boone, Callaway, Camden, Cass and 19 more88 min
Apr 8, 6:39 AM CDTSevere Thunderstorm WatchSPCAdair, Audrain, Barton, Bates, Benton, Boone and 54 more6 hr
Apr 8, 9:33 AM CDTMesoscale DiscussionSPCAdair, Audrain, Benton, Boone, Caldwell, Callaway and 45 more57 min
Apr 8, 2:21 PM CDTMesoscale DiscussionSPCBarry, Barton, Bates, Benton, Camden, Cass and 16 more114 min
Apr 8, 2:47 PM CDTSevere Thunderstorm WatchSPCBarry, Barton, Bates, Benton, Camden, Cass and 29 more4 hr
Apr 8, 5:45 PM CDTMesoscale DiscussionSPCAudrain, Bates, Benton, Boone, Caldwell, Callaway and 39 more60 min

Nearby

Mesoscale Discussions in Illinois, 2015Mesoscale Discussions in Indiana, 2015Mesoscale Discussions in Missouri, 2015Every mesoscale discussion in 2015

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.