Alert archive / Kentucky / Mesoscale Discussions in 2016

Mesoscale Discussion 608

May 11, 2016Gallatin County, Hardin County, Illinois; 6 counties in Indiana; 33 counties in Kentucky

The Storm Prediction Center issued this mesoscale discussion at May 11, 2016, 5:30 PM CDT for Gallatin County, Hardin County, Illinois; 6 counties in Indiana; 33 counties in Kentucky. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
May 11, 2016, 5:30 PM CDT (22:30 UTC)
Expired
May 11, 2016, 7:30 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
40%
All 41 counties

Gallatin County, IL, Hardin County, IL, Harrison County, IN, Perry County, IN, Posey County, IN, Spencer County, IN, Vanderburgh County, IN, Warrick County, IN, Anderson County, KY, Boyle County, KY, Breckinridge County, KY, Bullitt County, KY, Butler County, KY, Casey County, KY, Crittenden County, KY, Daviess County, KY, Edmonson County, KY, Garrard County, KY, Grayson County, KY, Green County, KY, Hancock County, KY, Hardin County, KY, Hart County, KY, Henderson County, KY, Hopkins County, KY, Jefferson County, KY, Larue County, KY, Lincoln County, KY, Marion County, KY, McLean County, KY, Meade County, KY, Mercer County, KY, Muhlenberg County, KY, Nelson County, KY, Ohio County, KY, Shelby County, KY, Spencer County, KY, Taylor County, KY, Union County, KY, Washington County, KY, Webster County, KY

The radar

The Louisville radar (KLVX), 54 km from the middle of the area, began a volume at 22:30 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

Nashville Metro, TN (KBNA), launched 12:00Z, 10.5 hours before the alert went out and 163 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, Nashville Metro, TN at 12:00Z on 2016-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1524 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, Nashville Metro, TN at 12:00Z on 2016-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 269 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
1524 J/kg
Mixed-layer CIN
-49 J/kg
Mixed-layer LCL
790 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
269 m²/s²
0-3 km storm-relative helicity
233 m²/s²
Significant tornado parameter
1.3
Supercell composite
6.7

Open this sounding in Storm Lab

The text

As transmitted.

932 
ACUS11 KWNS 112231
SWOMCD
SPC MCD 112230 
KYZ000-INZ000-ILZ000-120030-

MESOSCALE DISCUSSION 0608
NWS STORM PREDICTION CENTER NORMAN OK
0530 PM CDT WED MAY 11 2016

AREAS AFFECTED...FAR SE IL...FAR SRN IND...WRN AND CNTRL KY

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 112230Z - 120030Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...A POTENTIAL FOR WIND DAMAGE AND LARGE HAIL MAY DEVELOP
SEWD INTO PARTS OF WRN AND CNTRL KY OVER THE NEXT FEW HOURS. WW
ISSUANCE MAY BECOME NECESSARY ACROSS THE AREA BY EARLY THIS EVENING.

DISCUSSION...LATEST SFC ANALYSIS SHOWS A CORRIDOR OF LOW-LEVEL
MOISTURE EXTENDING NEWD ALONG THE MS RIVER INTO THE LOWER OH VALLEY.
A POCKET OF HIGHER MOISTURE CONTENT IS LOCATED ACROSS FAR SERN IL
INTO SW IND AND SWD ACROSS WRN KY WHERE SFC DEWPOINTS ARE IN THE
LOWER 70S F. THIS IS CONTRIBUTING TO STRONG INSTABILITY WITH MLCAPE
ESTIMATED BY MESOSCALE ANALYSIS IN THE 2500 TO 3500 J/KG RANGE
ACROSS WRN AND CNTRL KY. THUNDERSTORMS ARE LOCATED ALONG THE NRN
EDGE OF THE STRONGEST INSTABILITY. THIS ACTIVITY IS BEING SUPPORTED
BY LARGE-SCALE ASCENT ASSOCIATED WITH A SHORTWAVE TROUGH EVIDENT ON
WATER VAPOR IMAGERY. THIS CONVECTION WILL CONTINUE TO MOVE EWD
ACROSS SW IND BUT MAY GRADUALLY DEVELOP SWD INTO THE STRONGER
INSTABILITY OVER WRN AND CNTRL KY OVER THE NEXT FEW HOURS. THE
WSR-88D VWP AT PADUCAH HAS VEERING WINDS WITH HEIGHT IN THE LOW
LEVELS ALONG WITH 0-6 KM SHEAR NEAR 35 KT. THIS WILL BE FAVORABLE
FOR MULTICELL ORGANIZATION ALONG THE OUTFLOW BOUNDARY. AN ISOLATED
SUPERCELL OR TWO WILL ALSO BE POSSIBLE WITH STORMS THAT HAVE ACCESS
TO THE STRONGEST INSTABILITY...ON THE SERN EDGE OF THE MCS. ISOLATED
LARGE HAIL AND WIND DAMAGE WILL BE POSSIBLE WITH SUPERCELLS.

..BROYLES/THOMPSON.. 05/11/2016

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

ATTN...WFO...LMK...PAH...

LAT...LON   37068663 37098601 37238488 37438450 37768448 38248518
            38298643 38168774 37798853 37268831 37068663

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 11, 11:20 AM CDTMesoscale DiscussionSPCBond, Calhoun, Christian, Clay, Clinton, Effingham and 11 more55 min
May 11, 12:10 PM CDTSevere Thunderstorm WatchSPCBond, Calhoun, Cass, Champaign, Christian, Clark and 48 more12 hr
May 11, 2:19 PM CDTMesoscale DiscussionSPCBond, Brown, Calhoun, Cass, Christian, Clark and 33 more56 min
May 11, 3:39 PM CDTMesoscale DiscussionSPCLawrence, Wabash66 min
May 11, 6:30 PM CDTSevere Thunderstorm WatchSPCBond, Calhoun, Clinton, Franklin, Gallatin, Greene and 19 more7 hr
May 11, 3:55 PM CDTSevere Thunderstorm WatchSPCBartholomew, Brown, Clay, Crawford, Daviess, Dubois and 25 more5 hr
May 10, 7:42 PM CDTMesoscale DiscussionSPCAdair, Allen, Barren, Calloway, Christian, Clinton and 9 more93 min
May 10, 11:39 PM CDTMesoscale DiscussionSPCBell, Breathitt, Clay, Estill, Floyd, Harlan and 18 more96 min
May 11, 2:40 AM CDTMesoscale DiscussionSPCAllen, Logan, Monroe, Simpson, Todd95 min

Nearby

Mesoscale Discussions in Kentucky, 2016Mesoscale Discussions in Indiana, 2016Mesoscale Discussions in Illinois, 2016Every mesoscale discussion in 2016

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.