Alert archive / Iowa / Mesoscale Discussions in 2015

Mesoscale Discussion 1113

June 22, 201522 counties in Iowa

The Storm Prediction Center issued this mesoscale discussion at Jun 22, 2015, 3:10 AM CDT for 22 counties in Iowa. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued
Jun 22, 2015, 3:10 AM CDT (08:10 UTC)
Expired
Jun 22, 2015, 4:45 AM CDT
In force
95 min
Issued by
the Storm Prediction Center
Chance of a watch
20%
All 22 counties

Benton County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Clayton County, IA, Delaware County, IA, Fayette County, IA, Floyd County, IA, Franklin County, IA, Grundy County, IA, Hancock County, IA, Hardin County, IA, Howard County, IA, Humboldt County, IA, Jones County, IA, Kossuth County, IA, Linn County, IA, Mitchell County, IA, Wright County, IA

The radar

The Des Moines radar (KDMX), 129 km from the middle of the area, began a volume at 08:13 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 00:00Z, 8.2 hours before the alert went out and 221 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 00:00Z on 2015-06-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 39 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 00:00Z on 2015-06-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -25 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
39 J/kg
Mixed-layer CIN
-235 J/kg
Mixed-layer LCL
1911 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
-25 m²/s²
0-3 km storm-relative helicity
203 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

The text

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

786 
ACUS11 KWNS 220810
SWOMCD
SPC MCD 220810 
IAZ000-220945-

MESOSCALE DISCUSSION 1113
NWS STORM PREDICTION CENTER NORMAN OK
0310 AM CDT MON JUN 22 2015

AREAS AFFECTED...NERN IA

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 220810Z - 220945Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...TSTM ACTIVITY IS EXPECTED PERSIST ACROSS NERN IA WITH SOME
INCREASE IN COVERAGE POSSIBLE. ENVIRONMENT OVER THE AREA IS
SUPPORTIVE OF STORM ORGANIZATION WITH SOME POTENTIAL FOR SVR HAIL.

DISCUSSION...LATEST SURFACE ANALYSIS PLACES A WARM FRONT FROM ABOUT
SHL SEWD TO CID WITH THE 70 DEG ISODROSOTHERM ACTING AS A GOOD
INDICATOR OF THE FRONT/S POSITION. NERN EDGE OF THE LOW-LEVEL JET IS
FOCUSED INTO THIS BOUNDARY WITH THE ASSOCIATED WAA FORCING THE
INCREASED TSTM ACTIVITY. WITH THE CONTINUED FOCUS OF THE LOW-LEVEL
JET COUPLED WITH INCREASING INSTABILITY...TSTM ACTIVITY IS EXPECTED
TO PERSIST WITH SOME INCREASE IN COVERAGE POSSIBLE. 

OVERALL ENVIRONMENT IS CHARACTERIZED BY ABUNDANT LOW-LEVEL MOISTURE
AND STRONG SHEAR /EFFECTIVE SHEAR RANGING FROM 50 TO 65 KT PER
MESOANALYSIS/. MID-LEVEL LAPSE RATES ALONG AND N OF THE WARM FRONT
ARE MODEST BUT SHOULD STILL BE STEEP ENOUGH TO SUPPORT INSTABILITY.
LATEST MESOANALYSIS ESTIMATED MUCAPE AROUND 15OO J/KG NEAR THE
ONGOING ACTIVITY. AS SUCH...SOME SVR HAIL IS POSSIBLE.

GIVEN THE ANTICIPATED MARGINAL AND ISOLATED NATURE OF THE SVR
THREAT...A WW IS NOT CURRENTLY EXPECTED BUT TRENDS ACROSS THE REGION
WILL BE MONITORED CLOSELY.

..MOSIER/MEAD.. 06/22/2015

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

ATTN...WFO...DVN...ARX...DMX...

LAT...LON   42379348 42799475 43289453 43439242 43089137 42109059
            41879161 42379348

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 22, 2:25 AM CDTSevere Thunderstorm WatchSPCClay, Dickinson, Lyon, O'Brien, Osceola, Sioux6 hr
Jun 22, 4:53 AM CDTMesoscale DiscussionSPCAllamakee, Cerro Gordo, Chickasaw, Clay, Clayton, Dickinson and 15 more2 hr
Jun 22, 5:33 AM CDTSevere Thunderstorm WatchSPCBlack Hawk, Boone, Bremer, Butler, Cerro Gordo, Emmet and 15 more6 hr
Jun 22, 6:03 AM CDTSevere Thunderstorm WatchSPCAllamakee, Chickasaw, Clayton, Fayette, Floyd, Howard and 2 more4 hr
Jun 22, 7:42 AM CDTMesoscale DiscussionSPCAllamakee, Benton, Black Hawk, Boone, Bremer, Buchanan and 36 more93 min
Jun 22, 8:08 AM CDTSevere Thunderstorm WatchSPCBenton, Buchanan, Cedar, Clinton, Delaware, Dubuque and 5 more4 hr
Jun 22, 9:39 AM CDTSevere Thunderstorm WatchSPCMuscatine, Scott3 hr
Jun 22, 1:22 PM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Audubon, Benton, Boone and 42 more113 min
Jun 22, 3:56 PM CDTTornado WatchSPCAppanoose, Benton, Cedar, Clinton, Davis, Des Moines and 23 more9 hr
Jun 22, 6:08 PM CDTMesoscale DiscussionSPCAppanoose, Cedar, Davis, Des Moines, Henry, Iowa and 17 more67 min

Nearby

Mesoscale Discussions in Iowa, 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.