Alert archive / Kentucky / Mesoscale Discussions in 2012

Mesoscale Discussion 586

April 25, 20126 states

The Storm Prediction Center issued this mesoscale discussion at Apr 25, 2012, 10:11 PM CDT for 6 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 25, 2012, 10:11 PM CDT (03:11 UTC)
Expired
Apr 26, 2012, 12:15 AM CDT
In force
2 hr
Issued by
the Storm Prediction Center
All 187 counties

Adams County, IL, Bond County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Christian County, IL, Clark County, IL, Clay County, IL, Clinton County, IL, Coles County, IL, Crawford County, IL, Cumberland County, IL, Douglas County, IL, Edgar County, IL, Edwards County, IL, Effingham County, IL, Fayette County, IL, Franklin County, IL, Gallatin County, IL, Greene County, IL, Hamilton County, IL, Jasper County, IL, Jefferson County, IL, Jersey County, IL, Lawrence County, IL, Macon County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Menard County, IL, Montgomery County, IL, Morgan County, IL, Moultrie County, IL, Perry County, IL, Pike County, IL, Richland County, IL, Saint Clair County, IL, Saline County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Shelby County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Bartholomew County, IN, Brown County, IN, Clark County, IN, Clay County, IN, Crawford County, IN, Daviess County, IN, Dearborn County, IN, Decatur County, IN, Dubois County, IN, Fayette County, IN, Floyd County, IN, Franklin County, IN, Gibson County, IN, Greene County, IN, Harrison County, IN, Jackson County, IN, Jefferson County, IN, Jennings County, IN, Johnson County, IN, Knox County, IN, Lawrence County, IN, Martin County, IN, Monroe County, IN, Morgan County, IN, Ohio County, IN, Orange County, IN, Owen County, IN, Perry County, IN, Pike County, IN, Posey County, IN, Putnam County, IN, Ripley County, IN, Rush County, IN, Scott County, IN, Shelby County, IN, Spencer County, IN, Sullivan County, IN, Switzerland County, IN, Union County, IN, Vanderburgh County, IN, Vigo County, IN, Warrick County, IN, Washington County, IN, Anderson County, KY, Bath County, KY, Boone County, KY, Bourbon County, KY, Boyd County, KY, Boyle County, KY, Bracken County, KY, Breathitt County, KY, Breckinridge County, KY, Bullitt County, KY, Campbell County, KY, Carroll County, KY, Carter County, KY, Casey County, KY, Clark County, KY, Clay County, KY, Daviess County, KY, Elliott County, KY, Estill County, KY, Fayette County, KY, Fleming County, KY, Floyd County, KY, Franklin County, KY, Gallatin County, KY, Garrard County, KY, Grant County, KY, Grayson County, KY, Greenup County, KY, Hancock County, KY, Hardin County, KY, Harrison County, KY, Henderson County, KY, Henry County, KY, Jackson County, KY, Jefferson County, KY, Jessamine County, KY, Johnson County, KY, Kenton County, KY, Knott County, KY, Larue County, KY, Lawrence County, KY, Lee County, KY, Lewis County, KY, Lincoln County, KY, Madison County, KY, Magoffin County, KY, Marion County, KY, Martin County, KY, Mason County, KY, McLean County, KY, Meade County, KY, Menifee County, KY, Mercer County, KY, Montgomery County, KY, Morgan County, KY, Nelson County, KY, Nicholas County, KY, Ohio County, KY, Oldham County, KY, Owen County, KY, Owsley County, KY, Pendleton County, KY, Perry County, KY, Pike County, KY, Powell County, KY, Robertson County, KY, Rockcastle County, KY, Rowan County, KY, Scott County, KY, Shelby County, KY, Spencer County, KY, Taylor County, KY, Trimble County, KY, Union County, KY, Washington County, KY, Webster County, KY, Wolfe County, KY, Woodford County, KY, City of Saint Louis, MO, Lincoln County, MO, Pike County, MO, Saint Charles County, MO, Saint Louis County, MO, Adams County, OH, Brown County, OH, Butler County, OH, Clermont County, OH, Clinton County, OH, Hamilton County, OH, Highland County, OH, Lawrence County, OH, Pike County, OH, Scioto County, OH, Warren County, OH, Cabell County, WV, Lincoln County, WV, Mingo County, WV, Wayne County, WV

The radar

The Evansville,IN radar (KVWX), 77 km from the middle of the area, began a volume at 03:10 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 00:00Z, 3.2 hours before the alert went out and 186 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 00:00Z on 2012-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1745 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 00:00Z on 2012-04-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 261 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
1745 J/kg
Mixed-layer CIN
-108 J/kg
Mixed-layer LCL
1353 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
261 m²/s²
0-3 km storm-relative helicity
449 m²/s²
Significant tornado parameter
1.2
Supercell composite
4.2

Open this sounding in Storm Lab

The text

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

948 
ACUS11 KWNS 260312
SWOMCD
SPC MCD 260311
WVZ000-KYZ000-OHZ000-VAZ000-INZ000-ILZ000-MOZ000-260515-

MESOSCALE DISCUSSION 0586
NWS STORM PREDICTION CENTER NORMAN OK
1011 PM CDT WED APR 25 2012

AREAS AFFECTED...ERN MO INTO CNTRL IL

CONCERNING...SEVERE THUNDERSTORM WATCH 187...

VALID 260311Z - 260515Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 187
CONTINUES.

AN ISOLATED HAIL THREAT WILL REMAIN FOR SEVERAL HOURS ACROSS A LARGE
AREA FROM NERN MO/CNTRL IL EWD ACROSS THE OH VALLEY.

ISOLATED HAIL STORMS PERSIST OVER WRN IL...JUST AHEAD OF A COLD AND
NEAR THE SURFACE LOW. WEAK CONVERGENCE WILL REMAIN FROM SRN IL INTO
IND THIS EVENING AS THE LOW PROGRESSES EWD. THE ONGOING ACTIVITY MAY
CYCLE UP AND DOWN AS IT TRAVELS SEWD ACROSS IL...PRODUCING HAIL.
WHILE SOME CIN EXISTS...IT IS NOT FORECAST TO TOTALLY CAP THE
AREA...AND PARAMETERS REMAIN VERY FAVORABLE FOR LARGE HAIL.

FARTHER E...INTO SRN OH AND ERN KY...A SEVERE STORM HAS FORMED ON
THE WRN FRINGE OF A BAND OF WARM ADVECTION CONVECTION...HAVING
ACCESS TO BETTER LAPSE RATES/MOISTURE. OTHER ACTIVITY WAS DEVELOPING
ON THE NOSE OF A 50+ KT WLY LOW LEVEL JET OVER KY. THIS BROAD AREA
OF LIFT SHOULD PERSIST...BUT SHOULD GRADUALLY OUTRUN THE BEST
INSTABILITY. AS A RESULT...THE BEST THREAT OF HAIL IS EXPECTED TO BE
OVER THE NEXT FEW HOURS...WANING AFTER 06Z INTO THE WRN VIRGINIAS.

..JEWELL.. 04/26/2012

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

ATTN...WFO...RLX...JKL...ILN...LMK...IND...PAH...ILX...LSX...
DVN...

LAT...LON   38389012 39139132 39719159 40199140 40349080 40118976
            39808805 39738578 39608394 39298313 38328204 37708210
            37248242 37128358 37478786 37868923 38389012

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 25, 7:47 PM CDTSevere Thunderstorm WatchSPCAdams, Bond, Brown, Calhoun, Cass, Christian and 32 more6 hr
Apr 26, 12:40 AM CDTSevere Thunderstorm WatchSPCEdwards, Franklin, Gallatin, Hamilton, Hardin, Jackson and 10 more6 hr
Apr 26, 2:23 AM CDTMesoscale DiscussionSPCEdwards, Franklin, Gallatin, Hamilton, Hardin, Jefferson and 8 more97 min
Apr 26, 4:07 AM CDTMesoscale DiscussionSPCBell, Clay, Knox, Laurel, Leslie, McCreary and 1 more83 min
Apr 26, 5:22 AM CDTSevere Thunderstorm WatchSPCMcCreary, Wayne, Whitley3 hr
Apr 26, 6:24 AM CDTMesoscale DiscussionSPCBell, Harlan, Leslie, Letcher, Perry96 min
Apr 26, 1:23 PM CDTMesoscale DiscussionSPCAdair, Allen, Barren, Bath, Bell, Boyd and 61 more2 hr
Apr 26, 2:11 PM CDTSevere Thunderstorm WatchSPCAdair, Allen, Barren, Bell, Breathitt, Calloway and 42 more6 hr
Apr 26, 3:22 PM CDTMesoscale DiscussionSPCAdair, Allen, Barren, Bell, Breathitt, Clay and 26 more83 min
Apr 26, 5:40 PM CDTMesoscale DiscussionSPCAdair, Allen, Barren, Bell, Breathitt, Clay and 23 more95 min

Nearby

Mesoscale Discussions in Kentucky, 2012Mesoscale Discussions in Illinois, 2012Mesoscale Discussions in Indiana, 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.