Alert archive / Kentucky / Mesoscale Discussions in 2012

Mesoscale Discussion 338

March 23, 201231 counties in Indiana; 38 counties in Kentucky

The Storm Prediction Center issued this mesoscale discussion at Mar 23, 2012, 6:08 PM EDT for 31 counties in Indiana; 38 counties in Kentucky. It was in force for 37 min.

The area

The outline as issued.

The facts

Issued
Mar 23, 2012, 6:08 PM EDT (22:08 UTC)
Expired
Mar 23, 2012, 6:45 PM EDT
In force
37 min
Issued by
the Storm Prediction Center
All 69 counties

Bartholomew County, IN, Brown County, IN, Clark County, IN, Crawford County, IN, Dearborn County, IN, Decatur County, IN, Fayette County, IN, Floyd County, IN, Franklin County, IN, Hancock County, IN, Harrison County, IN, Hendricks County, IN, Jackson County, IN, Jefferson County, IN, Jennings County, IN, Johnson County, IN, Lawrence County, IN, Marion County, IN, Monroe County, IN, Morgan County, IN, Ohio County, IN, Orange County, IN, Perry County, IN, Ripley County, IN, Rush County, IN, Scott County, IN, Shelby County, IN, Switzerland County, IN, Union County, IN, Washington County, IN, Wayne County, IN, Adair County, KY, Allen County, KY, Anderson County, KY, Barren County, KY, Breckinridge County, KY, Bullitt County, KY, Butler County, KY, Carroll County, KY, Clinton County, KY, Cumberland County, KY, Edmonson County, KY, Franklin County, KY, Gallatin County, KY, Grayson County, KY, Green County, KY, Hancock County, KY, Hardin County, KY, Hart County, KY, Henry County, KY, Jefferson County, KY, Larue County, KY, Logan County, KY, Marion County, KY, Meade County, KY, Metcalfe County, KY, Monroe County, KY, Nelson County, KY, Ohio County, KY, Oldham County, KY, Owen County, KY, Russell County, KY, Shelby County, KY, Simpson County, KY, Spencer County, KY, Taylor County, KY, Trimble County, KY, Warren County, KY, Washington County, KY

The radar

The Louisville radar (KLVX), 52 km from the middle of the area, began a volume at 22:10 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

Cncnati-Daytn, OH (KILN), launched 12:00Z, 10.1 hours before the alert went out and 210 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, Cncnati-Daytn, OH at 12:00Z on 2012-03-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 233 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, Cncnati-Daytn, OH at 12:00Z on 2012-03-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 3 square meters per square second.19395878Sfc1 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
233 J/kg
Mixed-layer CIN
-53 J/kg
Mixed-layer LCL
1093 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
3 m²/s²
0-3 km storm-relative helicity
82 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.

723 
ACUS11 KWNS 232208
SWOMCD
SPC MCD 232208 
KYZ000-INZ000-TNZ000-232245-

MESOSCALE DISCUSSION 0338
NWS STORM PREDICTION CENTER NORMAN OK
0508 PM CDT FRI MAR 23 2012

AREAS AFFECTED...PARTS OF CENTRAL/SRN IND AND WRN/CENTRAL KY

CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY 

VALID 232208Z - 232245Z

A TORNADO WATCH WILL BE COORDINATED SHORTLY WITH AFFECTED WFOS FROM
PARTS OF CENTRAL/SRN IND INTO CENTRAL KY.  

LATE AFTERNOON SURFACE ANALYSES SHOWED A BOUNDARY EXTENDING SWD FROM
WEST CENTRAL/SWRN IND THROUGH WEST CENTRAL KY TO NWRN AL. 
ENVIRONMENT IMMEDIATELY DOWNSTREAM OF THIS WIND SHIFT HAS
EXPERIENCED STRONG SURFACE HEATING CONTRIBUTING TO AN INCREASE IN
AVAILABLE SURFACE BASED INSTABILITY /MUCAPE UP TO 1000 J PER KG/. 
MEANWHILE...A SHORTWAVE TROUGH ROUNDING THE BASE OF A PROGRESSIVE
MID MS VALLEY CLOSED LOW WAS MOVING ENEWD THROUGH SERN MO/NERN AR AT
THIS TIME.  70-80 KT SWLY MIDLEVEL JET ACCOMPANYING THIS TROUGH WILL
OVERSPREAD THE DISCUSSION AREA THIS EVENING MAINTAINING DEEP LAYER
SHEAR FOR ADDITIONAL ORGANIZED STORMS.

AT 22Z...REGIONAL RADAR IMAGERY SHOWED DEEPER MOIST CONVECTION
DEVELOPING SWD ALONG THE WIND SHIFT INTO CENTRAL KY.  GIVEN THE
AFOREMENTIONED FACTORS AND BACKED E/SELY SURFACE WINDS ACROSS SRN
IND INTO CENTRAL KY...THE POTENTIAL EXISTS FOR AN INCREASE IN TSTM
ACTIVITY THIS EVENING WITH AN ATTENDANT THREAT FOR
TORNADOES...DAMAGING WINDS AND HAIL.

..PETERS.. 03/23/2012

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

ATTN...WFO...JKL...ILN...LMK...OHX...IND...PAH...

LAT...LON   39768669 39958487 38578483 37078498 36698506 36648714
            39078671 39768669

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 23, 10:46 AM EDTMesoscale DiscussionSPCDaviess, Dubois, Gibson, Greene, Knox, Martin and 6 more119 min
Mar 23, 12:44 PM EDTSevere Thunderstorm WatchSPCClay, Daviess, Gibson, Greene, Knox, Lawrence and 10 more7 hr
Mar 23, 2:28 PM EDTMesoscale DiscussionSPCClay, Daviess, Dubois, Gibson, Greene, Knox and 12 more62 min
Mar 23, 4:17 PM EDTMesoscale DiscussionSPCBartholomew, Benton, Boone, Brown, Carroll, Clay and 35 more58 min
Mar 23, 4:39 PM EDTSevere Thunderstorm WatchSPCBenton, Boone, Brown, Carroll, Cass, Clinton and 18 more4 hr
Mar 23, 6:25 PM EDTTornado WatchSPCBartholomew, Boone, Brown, Carroll, Clark, Clinton and 39 more7 hr

Nearby

Mesoscale Discussions in Kentucky, 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.