Alert archive / Georgia / Mesoscale Discussions in 2012

Mesoscale Discussion 151

February 24, 20124 states

The Storm Prediction Center issued this mesoscale discussion at Feb 24, 2012, 5:56 AM CST for 4 states. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued
Feb 24, 2012, 5:56 AM CST (11:56 UTC)
Expired
Feb 24, 2012, 7:30 AM CST
In force
94 min
Issued by
the Storm Prediction Center
All 142 counties

Autauga County, AL, Barbour County, AL, Bibb County, AL, Bullock County, AL, Calhoun County, AL, Chambers County, AL, Cherokee County, AL, Chilton County, AL, Clay County, AL, Cleburne County, AL, Coosa County, AL, Dallas County, AL, Elmore County, AL, Etowah County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Montgomery County, AL, Perry County, AL, Pike County, AL, Randolph County, AL, Russell County, AL, Shelby County, AL, St. Clair County, AL, Talladega County, AL, Tallapoosa County, AL, Baldwin County, GA, Banks County, GA, Barrow County, GA, Bartow County, GA, Bibb County, GA, Butts County, GA, Carroll County, GA, Chattahoochee County, GA, Cherokee County, GA, Clarke County, GA, Clayton County, GA, Cobb County, GA, Columbia County, GA, Coweta County, GA, Crawford County, GA, Dawson County, GA, DeKalb County, GA, Douglas County, GA, Elbert County, GA, Fannin County, GA, Fayette County, GA, Floyd County, GA, Forsyth County, GA, Franklin County, GA, Fulton County, GA, Gilmer County, GA, Glascock County, GA, Gordon County, GA, Greene County, GA, Gwinnett County, GA, Habersham County, GA, Hall County, GA, Hancock County, GA, Haralson County, GA, Harris County, GA, Hart County, GA, Heard County, GA, Henry County, GA, Houston County, GA, Jackson County, GA, Jasper County, GA, Jefferson County, GA, Jones County, GA, Lamar County, GA, Lincoln County, GA, Lumpkin County, GA, Macon County, GA, Madison County, GA, Marion County, GA, McDuffie County, GA, Meriwether County, GA, Monroe County, GA, Morgan County, GA, Murray County, GA, Muscogee County, GA, Newton County, GA, Oconee County, GA, Oglethorpe County, GA, Paulding County, GA, Peach County, GA, Pickens County, GA, Pike County, GA, Polk County, GA, Putnam County, GA, Rabun County, GA, Richmond County, GA, Rockdale County, GA, Schley County, GA, Spalding County, GA, Stephens County, GA, Stewart County, GA, Talbot County, GA, Taliaferro County, GA, Taylor County, GA, Towns County, GA, Troup County, GA, Twiggs County, GA, Union County, GA, Upson County, GA, Walton County, GA, Warren County, GA, Washington County, GA, White County, GA, Wilkes County, GA, Wilkinson County, GA, Cherokee County, NC, Clay County, NC, Cleveland County, NC, Haywood County, NC, Henderson County, NC, Jackson County, NC, Macon County, NC, Polk County, NC, Rutherford County, NC, Transylvania County, NC, Abbeville County, SC, Aiken County, SC, Anderson County, SC, Cherokee County, SC, Chester County, SC, Edgefield County, SC, Fairfield County, SC, Greenville County, SC, Greenwood County, SC, Lancaster County, SC, Laurens County, SC, Lexington County, SC, McCormick County, SC, Newberry County, SC, Oconee County, SC, Pickens County, SC, Richland County, SC, Saluda County, SC, Spartanburg County, SC, Union County, SC, York County, SC

The radar

The Atlanta radar (KFFC), 13 km from the middle of the area, began a volume at 11:57 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

Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 11.9 hours before the alert went out and 9 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, Peachtre/Fal Fld, GA at 00:00Z on 2012-02-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 212 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, Peachtre/Fal Fld, GA at 00:00Z on 2012-02-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 313 square meters per square second.1939587897117136Sfc1 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
212 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
1189 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
313 m²/s²
0-3 km storm-relative helicity
583 m²/s²
Significant tornado parameter
0.3
Supercell composite
3.5

Open this sounding in Storm Lab

The text

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

277 
ACUS11 KWNS 241157
SWOMCD
SPC MCD 241156
SCZ000-NCZ000-GAZ000-TNZ000-ALZ000-241330-

MESOSCALE DISCUSSION 0151
NWS STORM PREDICTION CENTER NORMAN OK
0556 AM CST FRI FEB 24 2012

AREAS AFFECTED...CENTRAL/ERN AL...CENTRAL/NRN GA...AND UPSTATE SC

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 241156Z - 241330Z

A TORNADO WATCH IS BEING CONSIDERED FOR ISSUANCE FROM PARTS OF
CENTRAL AND ERN AL THROUGH CENTRAL/NRN GA INTO UPSTATE SC...AND
POTENTIALLY INTO WRN NC.  PROBABILITY OF WW ISSUANCE BY 13-14Z IS
60-70 PERCENT.

IN ADDITION TO A CONTINUATION OF TSTM DEVELOPMENT ALONG A COLD FRONT
ADVANCING THROUGH NRN AL...REGIONAL RADAR IMAGERY/LIGHTNING DATA
SHOWED AN INCREASE IN TSTM ACTIVITY ACROSS CENTRAL AL/WRN GA SINCE
1045Z.  COLD AIR ADVECTION ABOVE 850 MB HAS RESULTED IN A WEAKENING
OF THE CAP THAT WAS EVIDENT ON THE 24/00Z BHM/ATL SOUNDINGS AND NOW
ERODED PER 12Z BHM SOUNDING.  THUS...GIVEN A MOIST WARM SECTOR /PW
VALUES RANGING FROM 1-1.5 INCH/ AND LAPSE RATES NEAR 7 C/KM...THE
MUCAPE IS ALREADY NEAR 1000 J/KG.  DESPITE A LACK OF STRONGER HEIGHT
FALLS ACROSS THE DISCUSSION AREA TODAY...UPWARD VERTICAL MOTION
WITHIN THE RIGHT ENTRANCE REGION OF A 150+ KT UPPER JET IN THE TN/OH
VALLEYS IS EXPECTED TO SUPPORT FURTHER TSTM DEVELOPMENT ENEWD FROM
THE ONGOING ACTIVITY.  THIS SCENARIO IS SUPPORTED BY MOST SHORT TERM
MODELS WHICH SUGGEST A CONTINUED INCREASE IN TSTM DEVELOPMENT THIS
MORNING FROM AL THROUGH CENTRAL/NRN GA TO UPSTATE SC/NC.

STRENGTHENING WSWLY DEEP LAYER WIND FIELDS /60-70 KT AT 700 MB AND
80-100 KT AT 500 MB/ WILL MAINTAIN STRONG BULK SHEAR FOR ORGANIZED
STORM DEVELOPMENT.  STRAIGHT HODOGRAPHS SUGGEST SPLITTING SUPERCELLS
WILL BE POSSIBLE WITH LOW LEVEL SHEAR SUFFICIENT FOR TORNADO
DEVELOPMENT...IN ADDITION TO DAMAGING WINDS AND HAIL.

..PETERS.. 02/24/2012

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

ATTN...WFO...CAE...GSP...MRX...FFC...TAE...BMX...MOB...

LAT...LON   33428712 34318561 35618331 35568155 34818065 33658083
            32748291 32108446 31738584 31848690 32238741 33428712

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 24, 7:48 AM CSTTornado WatchSPCAutauga, Baldwin, Barbour, Bullock, Butler, Chambers and 25 more7 hr
Feb 24, 9:49 AM CSTMesoscale DiscussionSPCBarbour, Bullock, Butler, Chambers, Coffee, Conecuh and 13 more56 min
Feb 24, 11:04 AM CSTTornado WatchSPCCoffee, Dale, Geneva, Henry, Houston7 hr
Feb 24, 12:50 PM CSTMesoscale DiscussionSPCHenry, Houston85 min
Feb 24, 3:11 PM CSTMesoscale DiscussionSPCCoffee, Dale, Geneva, Henry, Houston64 min
Feb 24, 8:17 AM CSTTornado WatchSPCFranklin, Habersham, Hart, Rabun, Stephens7 hr
Feb 24, 11:00 AM CSTMesoscale DiscussionSPCFannin, Rabun, Towns, Union60 min
Feb 24, 2:24 PM CSTMesoscale DiscussionSPCFannin, Rabun, Towns, Union66 min
Feb 24, 8:05 AM CSTMesoscale DiscussionSPCAlexander, Alleghany, Ashe, Avery, Buncombe, Burke and 29 more25 min
Feb 24, 10:10 AM CSTMesoscale DiscussionSPCBladen, Brunswick, Columbus, New Hanover, Onslow, Pender and 1 more65 min
Feb 24, 11:43 AM CSTMesoscale DiscussionSPCAlamance, Anson, Beaufort, Bertie, Bladen, Brunswick and 51 more92 min
Feb 24, 12:19 PM CSTTornado WatchSPCAlamance, Anson, Beaufort, Bertie, Bladen, Brunswick and 55 more7 hr
Feb 24, 3:45 PM CSTMesoscale DiscussionSPCAlamance, Beaufort, Bertie, Bladen, Brunswick, Camden and 51 more90 min

Nearby

Mesoscale Discussions in Georgia, 2012Mesoscale Discussions in Alabama, 2012Mesoscale Discussions in South Carolina, 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.