Alert archive / Kentucky / Mesoscale Discussions in 2012

Mesoscale Discussion 697

May 4, 201225 counties in Indiana; 38 counties in Kentucky; Clermont County, Ohio

The Storm Prediction Center issued this mesoscale discussion at May 4, 2012, 4:16 PM EDT for 25 counties in Indiana; 38 counties in Kentucky; Clermont County, Ohio. It was in force for 59 min.

The area

The outline as issued.

The facts

Issued
May 4, 2012, 4:16 PM EDT (20:16 UTC)
Expired
May 4, 2012, 5:15 PM EDT
In force
59 min
Issued by
the Storm Prediction Center
All 64 counties

Clark County, IN, Crawford County, IN, Daviess County, IN, Dubois County, IN, Floyd County, IN, Gibson County, IN, Greene County, IN, Harrison County, IN, Jackson County, IN, Jefferson County, IN, Jennings County, IN, Knox County, IN, Lawrence County, IN, Martin County, IN, Ohio County, IN, Orange County, IN, Perry County, IN, Pike County, IN, Ripley County, IN, Scott County, IN, Spencer County, IN, Switzerland County, IN, Vanderburgh County, IN, Warrick County, IN, Washington County, IN, Anderson County, KY, Boone County, KY, Boyle County, KY, Breckinridge County, KY, Bullitt County, KY, Campbell County, KY, Carroll County, KY, Daviess County, KY, Franklin County, KY, Gallatin County, KY, Grant County, KY, Grayson County, KY, Hancock County, KY, Hardin County, KY, Harrison County, KY, Henderson County, KY, Henry County, KY, Jefferson County, KY, Jessamine County, KY, Kenton County, KY, Larue County, KY, Marion County, KY, McLean County, KY, Meade County, KY, Mercer County, KY, Nelson County, KY, Ohio County, KY, Oldham County, KY, Owen County, KY, Pendleton County, KY, Scott County, KY, Shelby County, KY, Spencer County, KY, Trimble County, KY, Union County, KY, Washington County, KY, Webster County, KY, Woodford County, KY, Clermont County, OH

The radar

The Louisville radar (KLVX), 62 km from the middle of the area, began a volume at 20:17 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 nearest sounding before it

Cncnati-Daytn, OH (KILN), launched 12:00Z, 8.3 hours before the alert went out and 245 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 2012-05-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 476 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 2012-05-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 88 square meters per square second.1939Sfc1 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
476 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
540 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
88 m²/s²
0-3 km storm-relative helicity
44 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.

243 
ACUS11 KWNS 042017
SWOMCD
SPC MCD 042016
KYZ000-OHZ000-INZ000-ILZ000-042115-

MESOSCALE DISCUSSION 0697
NWS STORM PREDICTION CENTER NORMAN OK
0316 PM CDT FRI MAY 04 2012

AREAS AFFECTED...SRN IND...NWRN KY

CONCERNING...SEVERE THUNDERSTORM WATCH 238...

VALID 042016Z - 042115Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 238
CONTINUES.

SUMMARY...FAST-MOVING BOW ECHO WILL RACE ACROSS SRN IND INTO THE
LOUISVILLE KY METRO AREA.  DAMAGING WINDS AND HAIL ARE POSSIBLE WITH
THIS ACTIVITY.

DISCUSSION...WELL DEFINED BOW ECHO...CURRENTLY LOCATED FROM
ORANGE/CRAWFORD COUNTIES IN SRN IND...IS BEGINNING TO SURGE ESEWD AT
ROUGHLY 45KT.  THIS COMPACT CLUSTER OF STORMS WILL SOON MOVE INTO
THE LOUISVILLE KY METRO AREA WITH A THREAT FOR DAMAGING WINDS AND
HAIL.  OTHER ISOLATED STORMS ARE ATTEMPTING TO FORM AHEAD OF THIS
BOW OVER SERN IND BUT THE PRIMARY SEVERE THREAT IN THE SHORT TERM
WILL BE WITH THE SURGING BOW ECHO.

..DARROW.. 05/04/2012

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

ATTN...WFO...ILN...LMK...IND...PAH...ILX...

LAT...LON   39108741 39118404 37468476 37458804 39108741

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 3, 11:29 PM EDTMesoscale DiscussionSPCBenton, Jasper, Lake, Newton, Porter61 min
May 4, 12:34 AM EDTSevere Thunderstorm WatchSPCBenton, Jasper, Newton5 hr
May 4, 3:16 AM EDTMesoscale DiscussionSPCBenton, Jasper, Newton, Pulaski, White119 min
May 4, 12:36 PM EDTMesoscale DiscussionSPCClark, Crawford, Daviess, Dubois, Floyd, Gibson and 11 more84 min
May 4, 2:29 PM EDTSevere Thunderstorm WatchSPCBartholomew, Brown, Clark, Crawford, Daviess, Dearborn and 25 more5 hr
May 4, 7:52 PM EDTMesoscale DiscussionSPCBoone, Delaware, Fayette, Franklin, Hamilton, Hancock and 12 more53 min
May 4, 1:26 PM EDTMesoscale DiscussionSPCTrumbull2 hr

Nearby

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