Alert archive / Illinois / Mesoscale Discussions in 2015

Mesoscale Discussion 251

April 9, 20154 states

The Storm Prediction Center issued this mesoscale discussion at Apr 9, 2015, 3:12 PM CDT for 4 states. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
Apr 9, 2015, 3:12 PM CDT (20:12 UTC)
Expired
Apr 9, 2015, 4:45 PM CDT
In force
93 min
Issued by
the Storm Prediction Center
All 109 counties

Appanoose County, IA, Benton County, IA, Cedar County, IA, Clinton County, IA, Davis County, IA, Des Moines County, IA, Henry County, IA, Iowa County, IA, Jackson County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Mahaska County, IA, Marion County, IA, Monroe County, IA, Muscatine County, IA, Poweshiek County, IA, Scott County, IA, Van Buren County, IA, Wapello County, IA, Washington County, IA, Adams County, IL, Boone County, IL, Brown County, IL, Bureau County, IL, Calhoun County, IL, Carroll County, IL, Cass County, IL, Champaign County, IL, Christian County, IL, Cook County, IL, DeKalb County, IL, DeWitt County, IL, DuPage County, IL, Ford County, IL, Fulton County, IL, Greene County, IL, Grundy County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Iroquois County, IL, Jo Daviess County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Knox County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McHenry County, IL, McLean County, IL, Menard County, IL, Mercer County, IL, Morgan County, IL, Ogle County, IL, Peoria County, IL, Piatt County, IL, Pike County, IL, Putnam County, IL, Rock Island County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Stark County, IL, Stephenson County, IL, Tazewell County, IL, Vermilion County, IL, Warren County, IL, Whiteside County, IL, Will County, IL, Winnebago County, IL, Woodford County, IL, Lake County, IN, Newton County, IN, Adair County, MO, Audrain County, MO, Boone County, MO, Chariton County, MO, Clark County, MO, Cooper County, MO, Howard County, MO, Knox County, MO, Lewis County, MO, Lincoln County, MO, Linn County, MO, Macon County, MO, Marion County, MO, Monroe County, MO, Montgomery County, MO, Pettis County, MO, Pike County, MO, Putnam County, MO, Ralls County, MO, Randolph County, MO, Saline County, MO, Schuyler County, MO, Scotland County, MO, Shelby County, MO, Sullivan County, MO

The radar

The Quad Cities radar (KDVN), 75 km from the middle of the area, began a volume at 20:14 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

Davenport, (KDVN), launched 12:00Z, 8.2 hours before the alert went out and 76 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, Davenport, at 12:00Z on 2015-04-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 101 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, Davenport, at 12:00Z on 2015-04-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 323 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
101 J/kg
Mixed-layer CIN
-154 J/kg
Mixed-layer LCL
614 m above ground
0-6 km bulk shear
55 kt
0-1 km storm-relative helicity
323 m²/s²
0-3 km storm-relative helicity
253 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4

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 8, 7:04 PM CDTMesoscale DiscussionSPCFranklin, Gallatin, Hardin, Jackson, Johnson, Pope and 3 more116 min
Apr 9, 12:29 PM CDTMesoscale DiscussionSPCBureau, Carroll, Henderson, Henry, Jo Daviess, Knox and 8 more91 min
Apr 9, 12:58 PM CDTTornado WatchSPCAdams, Brown, Carroll, Hancock, Henderson, Henry and 8 more6 hr
Apr 9, 1:48 PM CDTTornado WatchSPCBoone, Bureau, Cass, Champaign, Christian, Cook and 36 more9 hr
Apr 9, 3:45 PM CDTMesoscale DiscussionSPCAlexander, Bond, Clay, Clinton, Cumberland, Effingham and 25 more60 min
Apr 9, 4:40 PM CDTTornado WatchSPCBond, Calhoun, Clinton, Fayette, Greene, Jersey and 8 more6 hr
Apr 9, 6:04 PM CDTMesoscale DiscussionSPCBoone, Bureau, Carroll, Cass, DeKalb, DeWitt and 37 more86 min
Apr 9, 6:48 PM CDTTornado WatchSPCAlexander, Clark, Clay, Coles, Crawford, Cumberland and 26 more6 hr
Apr 9, 12:51 PM CDTMesoscale DiscussionSPCDearborn54 min
Apr 9, 1:26 PM CDTSevere Thunderstorm WatchSPCDearborn, Ohio, Ripley, Switzerland8 hr
Apr 9, 3:01 PM CDTMesoscale DiscussionSPCDearborn, Ohio, Ripley, Switzerland59 min
Apr 9, 3:49 PM CDTMesoscale DiscussionSPCClark, Dearborn, Floyd, Franklin, Jefferson, Jennings and 5 more56 min
Apr 9, 1:32 PM CDTMesoscale DiscussionSPCBarry, Barton, Benton, Camden, Cedar, Dade and 11 more118 min
Apr 9, 2:32 PM CDTSevere Thunderstorm WatchSPCBarry, Benton, Camden, Christian, Dade, Dallas and 22 more7 hr
Apr 9, 6:11 PM CDTMesoscale DiscussionSPCButler, Carter, Dunklin, Mississippi, New Madrid, Oregon and 5 more64 min
Apr 9, 6:32 PM CDTSevere Thunderstorm WatchSPCDunklin, Pemiscot5 hr

Nearby

Mesoscale Discussions in Illinois, 2015Mesoscale Discussions in Iowa, 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.