Alert archive / Iowa / Mesoscale Discussions in 2014

Mesoscale Discussion 581

May 12, 201422 counties in Illinois; 37 counties in Iowa; 24 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at May 12, 2014, 11:54 AM CDT for 22 counties in Illinois; 37 counties in Iowa; 24 counties in Missouri. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
May 12, 2014, 11:54 AM CDT (16:54 UTC)
Expired
May 12, 2014, 2:00 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 83 counties

Appanoose County, IA, Benton County, IA, Cedar County, IA, Clarke County, IA, Clinton County, IA, Davis County, IA, Decatur County, IA, Des Moines County, IA, Henry County, IA, Iowa County, IA, Jackson County, IA, Jasper County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Monroe County, IA, Muscatine County, IA, Polk County, IA, Poweshiek County, IA, Ringgold County, IA, Scott County, IA, Tama County, IA, Union County, IA, Van Buren County, IA, Wapello County, IA, Warren County, IA, Washington County, IA, Wayne County, IA, Adams County, IL, Brown County, IL, Bureau County, IL, Carroll County, IL, Fulton County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Jo Daviess County, IL, Knox County, IL, Lee County, IL, Marshall County, IL, McDonough County, IL, Mercer County, IL, Ogle County, IL, Peoria County, IL, Putnam County, IL, Rock Island County, IL, Schuyler County, IL, Stark County, IL, Warren County, IL, Whiteside County, IL, Adair County, MO, Caldwell County, MO, Carroll County, MO, Chariton County, MO, Clark County, MO, Daviess County, MO, Gentry County, MO, Grundy County, MO, Harrison County, MO, Knox County, MO, Lewis County, MO, Linn County, MO, Livingston County, MO, Macon County, MO, Marion County, MO, Mercer County, MO, Putnam County, MO, Randolph County, MO, Ray County, MO, Schuyler County, MO, Scotland County, MO, Shelby County, MO, Sullivan County, MO, Worth County, MO

The radar

The Quad Cities radar (KDVN), 114 km from the middle of the area, began a volume at 16:57 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, 4.9 hours before the alert went out and 121 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 2014-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 850 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 2014-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 223 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
850 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
666 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
223 m²/s²
0-3 km storm-relative helicity
216 m²/s²
Significant tornado parameter
0.0
Supercell composite
5.6

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
May 11, 8:32 PM CDTMesoscale DiscussionSPCDeWitt, Ford, Iroquois, Livingston, McLean58 min
May 12, 9:51 AM CDTMesoscale DiscussionSPCBoone, Bureau, Carroll, Cook, DeKalb, DuPage and 13 more84 min
May 12, 10:02 AM CDTSevere Thunderstorm WatchSPCBoone, Cook, DeKalb, DuPage, Kane, Lake and 4 more6 hr
May 12, 1:00 PM CDTSevere Thunderstorm WatchSPCAdams, Bureau, Carroll, Hancock, Henderson, Henry and 8 more7 hr
May 12, 1:06 PM CDTMesoscale DiscussionSPCBoone, Cook, DeKalb, DuPage, Kane, Lake and 6 more54 min
May 12, 3:21 PM CDTMesoscale DiscussionSPCAdams, Hancock, Henderson, Jo Daviess, McDonough, Mercer and 2 more54 min
May 12, 3:49 PM CDTSevere Thunderstorm WatchSPCBoone, Cook, DeKalb, DuPage, Kane, Kendall and 6 more7 hr
May 12, 6:56 PM CDTMesoscale DiscussionSPCBoone, Jo Daviess, Lake, McHenry, Stephenson, Winnebago64 min
May 11, 7:04 PM CDTMesoscale DiscussionSPCAdair, Audubon, Boone, Calhoun, Carroll, Clarke and 21 more56 min
May 11, 7:49 PM CDTTornado WatchSPCAdair, Adams, Appanoose, Audubon, Black Hawk, Boone and 38 more7 hr
May 11, 9:31 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Boone, Buena Vista, Calhoun and 31 more59 min
May 11, 9:56 PM CDTSevere Thunderstorm WatchSPCFremont, Mills, Montgomery, Page6 hr
May 11, 11:01 PM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Audubon, Black Hawk, Boone and 40 more59 min
May 12, 2:38 AM CDTMesoscale DiscussionSPCBates, Buchanan, Carroll, Cass, Clay, Clinton and 8 more2 hr
May 12, 3:15 AM CDTSevere Thunderstorm WatchSPCCaldwell, Carroll, Cass, Chariton, Clay, Clinton and 13 more3 hr
May 12, 11:52 AM CDTMesoscale DiscussionSPCMcDonald, Newton83 min
May 12, 2:12 PM CDTMesoscale DiscussionSPCAudrain, Barry, Barton, Bates, Benton, Boone and 37 more2 hr

Nearby

Mesoscale Discussions in Iowa, 2014Mesoscale Discussions in Missouri, 2014Mesoscale Discussions in Illinois, 2014Every mesoscale discussion in 2014

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.