Alert archive / Indiana / Mesoscale Discussions in 2011

Mesoscale Discussion 587

April 26, 20114 states

The Storm Prediction Center issued this mesoscale discussion at Apr 26, 2011, 12:26 PM CDT for 4 states. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued
Apr 26, 2011, 12:26 PM CDT (17:26 UTC)
Expired
Apr 26, 2011, 2:00 PM CDT
In force
94 min
Issued by
the Storm Prediction Center
All 110 counties

Champaign County, IL, Clark County, IL, Douglas County, IL, Edgar County, IL, Ford County, IL, Iroquois County, IL, Vermilion County, IL, Adams County, IN, Allen County, IN, Bartholomew County, IN, Benton County, IN, Blackford County, IN, Boone County, IN, Brown County, IN, Carroll County, IN, Cass County, IN, Clay County, IN, Clinton County, IN, Dearborn County, IN, Decatur County, IN, DeKalb County, IN, Delaware County, IN, Elkhart County, IN, Fayette County, IN, Fountain County, IN, Franklin County, IN, Fulton County, IN, Grant County, IN, Greene County, IN, Hamilton County, IN, Hancock County, IN, Hendricks County, IN, Henry County, IN, Howard County, IN, Huntington County, IN, Jasper County, IN, Jay County, IN, Jennings County, IN, Johnson County, IN, Kosciusko County, IN, LaGrange County, IN, LaPorte County, IN, Madison County, IN, Marion County, IN, Marshall County, IN, Miami County, IN, Monroe County, IN, Montgomery County, IN, Morgan County, IN, Newton County, IN, Noble County, IN, Owen County, IN, Parke County, IN, Pulaski County, IN, Putnam County, IN, Randolph County, IN, Ripley County, IN, Rush County, IN, Saint Joseph County, IN, Shelby County, IN, Starke County, IN, Steuben County, IN, Sullivan County, IN, Tippecanoe County, IN, Tipton County, IN, Union County, IN, Vermillion County, IN, Vigo County, IN, Wabash County, IN, Warren County, IN, Wayne County, IN, Wells County, IN, White County, IN, Whitley County, IN, Barry County, MI, Branch County, MI, Calhoun County, MI, Cass County, MI, Clinton County, MI, Eaton County, MI, Hillsdale County, MI, Ingham County, MI, Ionia County, MI, Jackson County, MI, Kalamazoo County, MI, Kent County, MI, Lenawee County, MI, Livingston County, MI, Monroe County, MI, Oakland County, MI, Saint Joseph County, MI, Shiawassee County, MI, Washtenaw County, MI, Allen County, OH, Auglaize County, OH, Darke County, OH, Defiance County, OH, Fulton County, OH, Hancock County, OH, Henry County, OH, Lucas County, OH, Mercer County, OH, Miami County, OH, Paulding County, OH, Preble County, OH, Putnam County, OH, Shelby County, OH, Van Wert County, OH, Williams County, OH, Wood County, OH

The radar

The Northern Indiana radar (KIWX), 51 km from the middle of the area, began a volume at 17:30 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, 5.4 hours before the alert went out and 233 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 2011-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 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 2011-04-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 123 square meters per square second.1939587897117136Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
615 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
123 m²/s²
0-3 km storm-relative helicity
131 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

334 
ACUS11 KWNS 261727
SWOMCD
SPC MCD 261726
OHZ000-MIZ000-KYZ000-INZ000-ILZ000-261900-

MESOSCALE DISCUSSION 0587
NWS STORM PREDICTION CENTER NORMAN OK
1226 PM CDT TUE APR 26 2011

AREAS AFFECTED...EASTERN IL INTO MUCH OF INDIANA/WESTERN OH AND
SOUTHERN LOWER MI

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 261726Z - 261900Z

THE SEVERE THREAT IS EXPECTED TO GRADUALLY INCREASE THROUGH THE
AFTERNOON FROM EASTERN IL INTO MUCH OF INDIANA/SOUTHERN LOWER MI AND
EVENTUALLY WESTERN OH. A WATCH MAY BE NEEDED FOR AT LEAST PORTIONS
OF THE REGION.

AS THE BRUNT OF A LEAD SHORTWAVE TROUGH CONTINUES TO PIVOT
NORTHEASTWARD TOWARD THE UPPER GREAT LAKES REGION...MIDDAY  SURFACE
ANALYSIS REFLECTS A SURFACE LOW OVER THE UPPER MS VALLEY...WITH AN
ASSOCIATED COLD FRONT EXTENDING SOUTH-SOUTHWESTWARD INTO THE MIDDLE
MS VALLEY. ALONG/EAST OF A COLD FRONT AMID A REGION OF LOW LEVEL
CONFLUENCE...TSTMS ARE EXPECTED TO CONTINUE TO DEVELOP WITHIN AN
INCREASINGLY UNSTABLE/WEAKLY CAPPED BOUNDARY FROM EASTERN IL INTO
MUCH OF INDIANA/WESTERN OH AND SOUTHERN LOWER MI...WHERE MODEST
CLOUD BREAKS ARE OCCURRING COINCIDENT WITH UPPER 50S F SURFACE
DEWPOINTS. AS STORMS MATURE...STRONG LOW-MID TROPOSPHERIC
SOUTHWESTERLY FLOW WILL YIELD FAST NORTHEASTWARD-MOVING
TSTMS...INCLUDING A FEW SUPERCELLS/ORGANIZED LINE SEGMENTS...CAPABLE
OF DAMAGING WINDS/SEVERE HAIL AND PERHAPS A TORNADO. CONVECTIVE
TRENDS WILL CONTINUE TO BE MONITORED FOR THE POSSIBILITY OF A WATCH.

..GUYER.. 04/26/2011

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

ATTN...WFO...CLE...ILN...DTX...IWX...GRR...IND...LOT...ILX...

LAT...LON   39028813 40498840 41428708 42508592 43338535 42958335
            41298337 38988492 39028813

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 25, 7:34 PM CDTMesoscale DiscussionSPCAlexander, Franklin, Gallatin, Hardin, Jackson, Johnson and 7 more116 min
Apr 25, 11:05 PM CDTMesoscale DiscussionSPCGallatin, Hardin, Massac, Pope, Saline, White115 min
Apr 26, 2:02 PM CDTTornado WatchSPCChampaign, Clark, Coles, Cumberland, Douglas, Edgar and 2 more7 hr
Apr 26, 2:41 PM CDTMesoscale DiscussionSPCMassac94 min
Apr 26, 3:02 PM CDTTornado Watch PDSSPCHardin, Massac, Pope7 hr
Apr 26, 4:38 PM CDTMesoscale DiscussionSPCClark, Crawford, Edwards, Gallatin, Hamilton, Jasper and 5 more37 min
Apr 26, 4:50 PM CDTTornado WatchSPCGallatin, Saline, Wabash, White5 hr
Apr 26, 6:17 PM CDTMesoscale DiscussionSPCAlexander, Hardin, Johnson, Massac, Pope, Pulaski and 1 more118 min
Apr 26, 3:53 PM CDTMesoscale DiscussionSPCCarroll, Cass, Elkhart, Fulton, Howard, Jasper and 13 more67 min

Nearby

Mesoscale Discussions in Indiana, 2011Mesoscale Discussions in Michigan, 2011Mesoscale Discussions in Ohio, 2011Every mesoscale discussion in 2011

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.