Alert archive / Iowa / Mesoscale Discussions in 2012

Mesoscale Discussion 1114

June 10, 20124 states

The Storm Prediction Center issued this mesoscale discussion at Jun 10, 2012, 3:10 PM CDT for 4 states. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued
Jun 10, 2012, 3:10 PM CDT (20:10 UTC)
Expired
Jun 10, 2012, 4:15 PM CDT
In force
65 min
Issued by
the Storm Prediction Center
Chance of a watch
80%
All 65 counties

Adair County, IA, Adams County, IA, Audubon County, IA, Boone County, IA, Buena Vista County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Cherokee County, IA, Clay County, IA, Crawford County, IA, Dallas County, IA, Dickinson County, IA, Emmet County, IA, Fremont County, IA, Greene County, IA, Guthrie County, IA, Harrison County, IA, Humboldt County, IA, Ida County, IA, Kossuth County, IA, Madison County, IA, Mills County, IA, Monona County, IA, Montgomery County, IA, O'Brien County, IA, Osceola County, IA, Page County, IA, Palo Alto County, IA, Plymouth County, IA, Pocahontas County, IA, Pottawattamie County, IA, Ringgold County, IA, Sac County, IA, Shelby County, IA, Sioux County, IA, Taylor County, IA, Union County, IA, Webster County, IA, Woodbury County, IA, Atchison County, KS, Brown County, KS, Doniphan County, KS, Nemaha County, KS, Andrew County, MO, Atchison County, MO, Buchanan County, MO, DeKalb County, MO, Gentry County, MO, Holt County, MO, Nodaway County, MO, Worth County, MO, Burt County, NE, Cass County, NE, Dodge County, NE, Douglas County, NE, Johnson County, NE, Nemaha County, NE, Otoe County, NE, Pawnee County, NE, Richardson County, NE, Sarpy County, NE, Saunders County, NE, Thurston County, NE, Washington County, NE

The radar

The Omaha radar (KOAX), 75 km from the middle of the area, began a volume at 20:12 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

Omaha, NE (KOAX), launched 12:00Z, 8.2 hours before the alert went out and 75 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, Omaha, NE at 12:00Z on 2012-06-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1119 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, Omaha, NE at 12:00Z on 2012-06-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 131 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
1119 J/kg
Mixed-layer CIN
-368 J/kg
Mixed-layer LCL
1000 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
131 m²/s²
0-3 km storm-relative helicity
158 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

982 
ACUS11 KWNS 102011
SWOMCD
SPC MCD 102010
IAZ000-MOZ000-KSZ000-NEZ000-SDZ000-102115-

MESOSCALE DISCUSSION 1114
NWS STORM PREDICTION CENTER NORMAN OK
0310 PM CDT SUN JUN 10 2012

AREAS AFFECTED...WRN IA...SERN NEB...FAR NWRN MO...FAR NERN KS

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 102010Z - 102115Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...INITIATION OF TSTMS IS BECOMING MORE PROBABLE ALONG A SEWD
ADVANCING COLD FRONT. PRIMARY RISKS OF LARGE HAIL AND DMGG WINDS ARE
EXPECTED...AND A WW MAY BE NECESSARY BY 22Z.

DISCUSSION...20Z SFC ANALYSIS SHOWS A COLD FRONT ARCING SWWD AND
THEN WSWWD ACROSS SRN NEB/NRN KS...ADVANCING TOWARDS THE SE. WATER
VAPOR LOOP SHOWS A WELL-DEFINED UPPER TROUGH OVER THE NRN
PLAINS...WITH INFLUENCE OF LEADING EDGE OF FORCED ASCENT/MIDLEVEL
HEIGHT FALLS DECREASING WITH SWD EXTENT. HOWEVER...STRONG
CONVERGENCE ALONG THE COLD FRONT...ALONG WITH A HOT/WELL-MIXED
BOUNDARY LAYER...WILL BE SUFFICIENT TO WEAKEN ANY REMAINING CINH AND
LEAD TO RAPID DEVELOPMENT OF TSTMS ALONG THE COLD FRONT THIS
AFTERNOON...PARTICULARLY ACROSS WRN IA.

VERY HOT BOUNDARY LAYER TEMPERATURES /APPROACHING THE MID 90S ACROSS
SWRN IA/ COMBINED WITH MID-UPPER 60S SFC DEWPOINTS WILL YIELD MLCAPE
VALUES RANGING FROM 1500-3000 J/KG. INITIAL CONVECTIVE DEVELOPMENT
SHOULD FAVOR CLUSTERS ALONG/AHEAD OF THE COLD FRONT ACROSS WRN
IA...WHILE FARTHER S...WEAKER FORCED ASCENT AND VEERING MIDLEVEL
WINDS ALONG THE SRN PERIPHERY OF THE UPPER TROUGH MAY BE MORE
FAVORABLE FOR DISCRETE STORMS OR SMALL LINE SEGMENTS INITIALLY. A
THREAT FOR DMGG WIND GUSTS...OWING TO STRONG BACKGROUND LOW-LEVEL
FLOW AND A HOT/WELL-MIXED BOUNDARY LAYER...WILL EXIST. LARGE HAIL
MAY ALSO ACCOMPANY THE STRONGEST STORMS...PARTICULARLY ACROSS SRN
PORTIONS OF THE HIGHLIGHTED AREA.

..ROGERS/MEAD.. 06/10/2012

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...DMX...EAX...FSD...OAX...TOP...

LAT...LON   41949664 43369631 43499540 43449432 42689387 40559406
            39839444 39449479 39449607 40239661 40849668 41949664

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 10, 3:42 PM CDTSevere Thunderstorm WatchSPCAdair, Adams, Audubon, Boone, Buena Vista, Calhoun and 45 more7 hr
Jun 10, 6:20 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Boone, Buena Vista, Calhoun and 37 more55 min

Nearby

Mesoscale Discussions in Iowa, 2012Mesoscale Discussions in Nebraska, 2012Mesoscale Discussions in Missouri, 2012Every mesoscale discussion in 2012

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.