Alert archive / Kentucky / Mesoscale Discussions in 2012

Mesoscale Discussion 1564

July 24, 201232 counties in Kentucky; 4 counties in Virginia; 6 counties in West Virginia

The Storm Prediction Center issued this mesoscale discussion at Jul 24, 2012, 11:43 AM EDT for 32 counties in Kentucky; 4 counties in Virginia; 6 counties in West Virginia. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued
Jul 24, 2012, 11:43 AM EDT (15:43 UTC)
Expired
Jul 24, 2012, 12:45 PM EDT
In force
62 min
Issued by
the Storm Prediction Center
Chance of a watch
95%
All 42 counties

Bath County, KY, Bourbon County, KY, Boyd County, KY, Breathitt County, KY, Carter County, KY, Clark County, KY, Clay County, KY, Elliott County, KY, Estill County, KY, Fleming County, KY, Floyd County, KY, Harlan County, KY, Jackson County, KY, Johnson County, KY, Knott County, KY, Lawrence County, KY, Lee County, KY, Leslie County, KY, Letcher County, KY, Lewis County, KY, Magoffin County, KY, Martin County, KY, Menifee County, KY, Montgomery County, KY, Morgan County, KY, Nicholas County, KY, Owsley County, KY, Perry County, KY, Pike County, KY, Powell County, KY, Rowan County, KY, Wolfe County, KY, Buchanan County, VA, City of Norton, VA, Dickenson County, VA, Wise County, VA, Boone County, WV, Cabell County, WV, Lincoln County, WV, Logan County, WV, Mingo County, WV, Wayne County, WV

The radar

The Jackson,KY radar (KJKL), 34 km from the middle of the area, began a volume at 15:46 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, 3.7 hours before the alert went out and 185 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 2012-07-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1858 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 2012-07-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 187 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
1858 J/kg
Mixed-layer CIN
-130 J/kg
Mixed-layer LCL
1124 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
187 m²/s²
0-3 km storm-relative helicity
154 m²/s²
Significant tornado parameter
0.4
Supercell composite
1.7

Open this sounding in Storm Lab

The text

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

281 
ACUS11 KWNS 241543
SWOMCD
SPC MCD 241543 
WVZ000-VAZ000-KYZ000-OHZ000-241645-

MESOSCALE DISCUSSION 1564
NWS STORM PREDICTION CENTER NORMAN OK
1043 AM CDT TUE JUL 24 2012

AREAS AFFECTED...ERN KY...FAR SRN OH...WRN/SRN WV...SWRN VA

CONCERNING...SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY 

VALID 241543Z - 241645Z

PROBABILITY OF WATCH ISSUANCE...95 PERCENT

SUMMARY...A NEW SVR TSTM WATCH WILL LIKELY BE ISSUED DOWNSTREAM OF
WW 508 WITHIN THE HOUR.

DISCUSSION...A SQUALL LINE WITH A HISTORY OF DMGG WIND GUSTS ACROSS
W-CNTRL OH AND ERN IND WILL CONTINUE ADVANCING SEWD/SSEWD AT 60-65
MPH INTO A DESTABILIZING AIR MASS OVER THE OHIO VALLEY. WITH STRONG
DEEP SHEAR AND STRONG INSTABILITY...THE FORWARD-PROPAGATING MCS WILL
POTENTIALLY OFFER A LONG-LIVED THREAT FOR WIDESPREAD DMGG WIND GUSTS
AS THE LINE CROSSES PARTS OF KY/WV/VA.

..COHEN/HART.. 07/24/2012

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

ATTN...WFO...RLX...MRX...JKL...ILN...LMK...

LAT...LON   38438438 38558333 38558205 37888143 36998202 36838321
            37188419 38438438

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 24, 10:35 AM EDTSevere Thunderstorm WatchSPCBoone, Bracken, Campbell, Kenton, Lewis, Mason and 2 more3 hr
Jul 24, 11:59 AM EDTMesoscale DiscussionSPCBoone, Bracken, Campbell, Greenup, Kenton, Lewis and 3 more61 min
Jul 24, 12:33 PM EDTSevere Thunderstorm WatchSPCAdair, Anderson, Bath, Bell, Bourbon, Boyd and 61 more6 hr
Jul 24, 1:52 PM EDTMesoscale DiscussionSPCAnderson, Bath, Bourbon, Boyd, Boyle, Breathitt and 47 more53 min
Jul 24, 3:25 PM EDTMesoscale DiscussionSPCAdair, Anderson, Bell, Bourbon, Boyle, Breathitt and 44 more95 min
Jul 24, 4:25 PM EDTMesoscale DiscussionSPCBreckinridge, Butler, Caldwell, Christian, Crittenden, Daviess and 17 more95 min
Jul 24, 6:20 PM EDTSevere Thunderstorm WatchSPCAdair, Allen, Barren, Bell, Breckinridge, Butler and 26 more4 hr
Jul 24, 11:48 AM EDTMesoscale DiscussionSPCArlington, Clarke, Culpeper, Fairfax, Fauquier, Frederick and 22 more87 min
Jul 24, 1:08 PM EDTSevere Thunderstorm WatchSPCAlbemarle, Alleghany, Amelia, Amherst, Appomattox, Arlington and 89 more6 hr
Jul 24, 1:42 PM EDTMesoscale DiscussionSPCAccomack, Amelia, Brunswick, Caroline, Charles City, Charlotte and 48 more2 hr
Jul 24, 3:46 PM EDTMesoscale DiscussionSPCAccomack, Brunswick, Charles City, Dinwiddie, Gloucester, Greensville and 28 more89 min
Jul 24, 4:24 PM EDTSevere Thunderstorm WatchSPCAccomack, Brunswick, Dinwiddie, Gloucester, Greensville, Isle of Wight and 20 more4 hr

Nearby

Mesoscale Discussions in Kentucky, 2012Mesoscale Discussions in West Virginia, 2012Mesoscale Discussions in Virginia, 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.