Alert archive / Tennessee / Mesoscale Discussions in 2012

Mesoscale Discussion 262

March 15, 20127 states

The Storm Prediction Center issued this mesoscale discussion at Mar 15, 2012, 6:23 PM CDT for 7 states. It was in force for 97 min.

The area

The outline as issued.

The facts

Issued
Mar 15, 2012, 6:23 PM CDT (23:23 UTC)
Expired
Mar 15, 2012, 8:00 PM CDT
In force
97 min
Issued by
the Storm Prediction Center
All 134 counties

Cherokee County, AL, DeKalb County, AL, Jackson County, AL, Limestone County, AL, Madison County, AL, Marshall County, AL, Morgan County, AL, Bartow County, GA, Catoosa County, GA, Chattooga County, GA, Cherokee County, GA, Dade County, GA, Dawson County, GA, Fannin County, GA, Floyd County, GA, Forsyth County, GA, Gilmer County, GA, Gordon County, GA, Lumpkin County, GA, Murray County, GA, Pickens County, GA, Polk County, GA, Towns County, GA, Union County, GA, Walker County, GA, Whitfield County, GA, Bath County, KY, Bell County, KY, Bourbon County, KY, Bracken County, KY, Breathitt County, KY, Campbell County, KY, Clark County, KY, Clay County, KY, Clinton County, KY, Estill County, KY, Fayette County, KY, Fleming County, KY, Garrard County, KY, Harlan County, KY, Harrison County, KY, Jackson County, KY, Jessamine County, KY, Kenton County, KY, Knox County, KY, Laurel County, KY, Lee County, KY, Leslie County, KY, Lincoln County, KY, Madison County, KY, Mason County, KY, McCreary County, KY, Menifee County, KY, Montgomery County, KY, Nicholas County, KY, Owsley County, KY, Pendleton County, KY, Perry County, KY, Powell County, KY, Pulaski County, KY, Robertson County, KY, Rockcastle County, KY, Rowan County, KY, Russell County, KY, Scott County, KY, Wayne County, KY, Whitley County, KY, Wolfe County, KY, Cherokee County, NC, Clay County, NC, Graham County, NC, Swain County, NC, Adams County, OH, Auglaize County, OH, Brown County, OH, Butler County, OH, Champaign County, OH, Clark County, OH, Clermont County, OH, Clinton County, OH, Darke County, OH, Greene County, OH, Hamilton County, OH, Highland County, OH, Mercer County, OH, Miami County, OH, Montgomery County, OH, Preble County, OH, Shelby County, OH, Warren County, OH, Anderson County, TN, Bedford County, TN, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Campbell County, TN, Cannon County, TN, Claiborne County, TN, Cocke County, TN, Coffee County, TN, Cumberland County, TN, DeKalb County, TN, Fentress County, TN, Franklin County, TN, Grainger County, TN, Grundy County, TN, Hamblen County, TN, Hamilton County, TN, Hancock County, TN, Jackson County, TN, Jefferson County, TN, Knox County, TN, Lincoln County, TN, Loudon County, TN, Marion County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Moore County, TN, Morgan County, TN, Overton County, TN, Pickett County, TN, Polk County, TN, Putnam County, TN, Rhea County, TN, Roane County, TN, Scott County, TN, Sequatchie County, TN, Sevier County, TN, Union County, TN, Van Buren County, TN, Warren County, TN, White County, TN, Lee County, VA

The radar

The Jackson,KY radar (KJKL), 116 km from the middle of the area, began a volume at 23:23 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

Nashville Metro, TN (KBNA), launched 12:00Z, 11.4 hours before the alert went out and 222 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 2012-03-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1726 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 2012-03-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 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
1726 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
820 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
108 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.

452 
ACUS11 KWNS 152323
SWOMCD
SPC MCD 152323 
VAZ000-KYZ000-TNZ000-NCZ000-GAZ000-OHZ000-INZ000-ALZ000-160100-

MESOSCALE DISCUSSION 0262
NWS STORM PREDICTION CENTER NORMAN OK
0623 PM CDT THU MAR 15 2012

AREAS AFFECTED...WRN OH...KY...TN...NRN AL AND NRN GA

CONCERNING...SEVERE THUNDERSTORM WATCH 75...77...

VALID 152323Z - 160100Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH
75...77...CONTINUES.

A MESOSCALE VORTEX CONTINUES TO MOVE EWD ACROSS KY...WITH NUMEROUS
STORMS CAPABLE OF HAIL AND HEAVY RAIN AHEAD OF IT EXTENDING FROM WRN
OH INTO ERN KY AND TN. HAIL CORES HAVE DECIDEDLY TRENDED DOWNWARD
OVER THE PAST HOUR...AND THIS TREND SHOULD CONTINUE AS STORMS RUN UP
AGAINST A MORE STABLE AIR MASS TO THE E IN THE WAKE OF AN EARLIER
MCS. THUS...MUCH OF THE AREA MAY BE CLEARED FROM THE SEVERE
THUNDERSTORM WATCHES AS INSTABILITY DECREASES.

FARTHER S INTO NRN AL AND GA...AMPLE INSTABILITY EXISTS BUT WIND
SHEAR IS QUITE WEAK. HOWEVER...ONGOING CONVECTION HAS LINED UP ALONG
LEADING EDGE OF SOME OUTFLOW...AND WITH A DEEPLY MIXED BOUNDARY
LAYER IN PLACE AHEAD OF THIS ACTIVITY...GUSTY OUTFLOW WINDS MAY
OCCUR. ISOLATED MARGINAL HAIL IS ALSO POSSIBLE...BUT TRENDS SHOULD
BE DOWN WITH TIME AS THE BOUNDARY LAYER BEGINS TO STABILIZE.

..JEWELL.. 03/15/2012

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

ATTN...WFO...GSP...MRX...JKL...FFC...ILN...LMK...IWX...OHX...
BMX...HUN...

LAT...LON   38228343 37198304 36288291 35348333 34138412 33928510
            34298682 34458714 34958714 36098604 36748517 37768472
            38828459 39588465 40618482 40758426 40508387 39578352
            38578346 38228343

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 15, 1:08 PM CDTMesoscale DiscussionSPCAdair, Allen, Anderson, Ballard, Barren, Bell and 90 more2 hr
Mar 15, 2:06 PM CDTSevere Thunderstorm WatchSPCAdair, Allen, Anderson, Barren, Bourbon, Boyle and 43 more6 hr
Mar 15, 3:44 PM CDTMesoscale DiscussionSPCAdair, Allen, Anderson, Barren, Bath, Boone and 74 more61 min
Mar 15, 4:28 PM CDTSevere Thunderstorm WatchSPCBoone, Bracken, Campbell, Carroll, Gallatin, Grant and 4 more3 hr
Mar 15, 2:19 AM CDTMesoscale DiscussionSPCAllen, Ashland, Champaign, Clark, Coshocton, Crawford and 41 more86 min
Mar 15, 2:52 PM CDTMesoscale DiscussionSPCAllen, Defiance, Fulton, Hancock, Henry, Lucas and 8 more83 min
Mar 15, 5:02 PM CDTMesoscale DiscussionSPCAllen, Defiance, Fulton, Henry, Lucas, Paulding and 4 more2 hr

Nearby

Mesoscale Discussions in Tennessee, 2012Mesoscale Discussions in Kentucky, 2012Mesoscale Discussions in Georgia, 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.