Alert archive / Kentucky / Mesoscale Discussions in 2012

Mesoscale Discussion 1891

September 5, 20124 states

The Storm Prediction Center issued this mesoscale discussion at Sep 5, 2012, 1:10 PM CDT for 4 states. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued
Sep 5, 2012, 1:10 PM CDT (18:10 UTC)
Expired
Sep 5, 2012, 2:15 PM CDT
In force
65 min
Issued by
the Storm Prediction Center
All 131 counties

Gallatin County, IL, Hardin County, IL, Johnson County, IL, Massac County, IL, Pope County, IL, Bartholomew County, IN, Brown County, IN, Clark County, IN, Crawford County, IN, Dearborn County, IN, Decatur County, IN, Dubois County, IN, Fayette County, IN, Floyd County, IN, Franklin County, IN, Harrison County, IN, Jackson County, IN, Jefferson County, IN, Jennings County, IN, Lawrence County, IN, Martin County, IN, Ohio County, IN, Orange County, IN, Perry County, IN, Pike County, IN, Ripley County, IN, Rush County, IN, Scott County, IN, Shelby County, IN, Spencer County, IN, Switzerland County, IN, Union County, IN, Vanderburgh County, IN, Warrick County, IN, Washington County, IN, Wayne County, IN, Anderson County, KY, Ballard County, KY, Bath County, KY, Boone County, KY, Bourbon County, KY, Boyle County, KY, Bracken County, KY, Breckinridge County, KY, Bullitt County, KY, Butler County, KY, Caldwell County, KY, Campbell County, KY, Carroll County, KY, Christian County, KY, Clark County, KY, Crittenden County, KY, Daviess County, KY, Edmonson County, KY, Fayette County, KY, Fleming County, KY, Franklin County, KY, Gallatin County, KY, Grant County, KY, Graves County, KY, Grayson County, KY, Green County, KY, Hancock County, KY, Hardin County, KY, Harrison County, KY, Hart County, KY, Henderson County, KY, Henry County, KY, Hopkins County, KY, Jefferson County, KY, Jessamine County, KY, Kenton County, KY, Larue County, KY, Lewis County, KY, Livingston County, KY, Logan County, KY, Lyon County, KY, Marion County, KY, Marshall County, KY, Mason County, KY, McCracken County, KY, McLean County, KY, Meade County, KY, Mercer County, KY, Montgomery County, KY, Muhlenberg County, KY, Nelson County, KY, Nicholas County, KY, Ohio County, KY, Oldham County, KY, Owen County, KY, Pendleton County, KY, Robertson County, KY, Scott County, KY, Shelby County, KY, Spencer County, KY, Taylor County, KY, Todd County, KY, Trigg County, KY, Trimble County, KY, Union County, KY, Warren County, KY, Washington County, KY, Webster County, KY, Woodford County, KY, Adams County, OH, Brown County, OH, Butler County, OH, Champaign County, OH, Clark County, OH, Clermont County, OH, Clinton County, OH, Darke County, OH, Fairfield County, OH, Fayette County, OH, Franklin County, OH, Greene County, OH, Hamilton County, OH, Highland County, OH, Hocking County, OH, Jackson County, OH, Madison County, OH, Miami County, OH, Montgomery County, OH, Pickaway County, OH, Pike County, OH, Preble County, OH, Ross County, OH, Scioto County, OH, Vinton County, OH, Warren County, OH

The radar

The Louisville radar (KLVX), 33 km from the middle of the area, began a volume at 18:13 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, 6.2 hours before the alert went out and 237 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 2012-09-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 746 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 2012-09-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -8 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
746 J/kg
Mixed-layer CIN
-52 J/kg
Mixed-layer LCL
667 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
-8 m²/s²
0-3 km storm-relative helicity
-4 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

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

735 
ACUS11 KWNS 051811
SWOMCD
SPC MCD 051810
OHZ000-KYZ000-INZ000-ILZ000-051915-

MESOSCALE DISCUSSION 1891
NWS STORM PREDICTION CENTER NORMAN OK
0110 PM CDT WED SEP 05 2012

AREAS AFFECTED...SRN IL...IND...SWRN OH...KY

CONCERNING...SEVERE THUNDERSTORM WATCH 619...

VALID 051810Z - 051915Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 619
CONTINUES.

SUMMARY...A LINE OF STORMS WILL CONTINUE EWD ACROSS THE OH RIVER
THIS AFTERNOON...WITH A THREAT OF DAMAGING WIND AND PERHAPS SOME
HAIL. AN ADDITIONAL WATCH IS LIKELY DOWNSTREAM OF THE EXISTING
WATCH.

DISCUSSION...STORMS EXTENDING FROM CNTRL IND INTO SRN IL ARE
EXPECTED TO MAINTAIN INTENSITY OR STRENGTHEN THROUGH THE AFTERNOON
AS THEY ENCOUNTER A MORE MOIST AND UNSTABLE AIR MASS TO THE SE. GPS
PWAT SENSORS INDICATE VALUES IN EXCESS OF 1.75 INCHES OVER CNTRL AND
WRN KY...AND MLCAPE IS APPROACHING 2000 J/KG.  ALTHOUGH MIDLEVEL
FLOW IS WLY...NWLY 700 MB FLOW AROUND 20 KT WILL HELP TO PUSH THE
SYSTEM IN A SEWD DIRECTION.

..JEWELL.. 09/05/2012

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

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

LAT...LON   37528899 38048782 39228625 39978520 40248456 40138267
            39828229 39018255 37958383 37268555 36768699 36698778
            36708880 36968904 37528899

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 4, 8:30 PM CDTMesoscale DiscussionSPCJo Daviess60 min
Sep 4, 8:51 PM CDTSevere Thunderstorm WatchSPCBoone, Carroll, Cook, DeKalb, DuPage, Grundy and 13 more5 hr
Sep 5, 1:14 AM CDTMesoscale DiscussionSPCCarroll, Henry, Jo Daviess, Rock Island, Stephenson, Whiteside and 1 more91 min
Sep 5, 3:43 AM CDTMesoscale DiscussionSPCBoone, Bureau, Carroll, DeKalb, Grundy, Henderson and 21 more92 min
Sep 5, 9:04 AM CDTMesoscale DiscussionSPCAlexander, Bond, Clark, Clay, Clinton, Crawford and 28 more86 min
Sep 5, 9:37 AM CDTSevere Thunderstorm WatchSPCBond, Clark, Clay, Clinton, Coles, Crawford and 24 more6 hr
Sep 5, 1:43 PM CDTSevere Thunderstorm WatchSPCHardin5 hr
Sep 5, 2:13 PM CDTMesoscale DiscussionSPCAlexander, Massac, Pulaski2 hr
Sep 5, 2:29 PM CDTSevere Thunderstorm WatchSPCAlexander, Johnson, Massac, Pope, Pulaski, Union8 hr
Sep 5, 4:02 PM CDTMesoscale DiscussionSPCBoone, Carroll, Cook, DeKalb, DuPage, Jo Daviess and 7 more88 min
Sep 5, 5:31 PM CDTMesoscale DiscussionSPCAdair, Allen, Bath, Bourbon, Boyle, Casey and 28 more89 min

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.