Alert archive / Georgia / Mesoscale Discussions in 2012

Mesoscale Discussion 153

February 24, 201219 counties in Alabama; 63 counties in Georgia; Aiken County, South Carolina

The Storm Prediction Center issued this mesoscale discussion at Feb 24, 2012, 9:49 AM CST for 19 counties in Alabama; 63 counties in Georgia; Aiken County, South Carolina. It was in force for 56 min.

The area

The outline as issued.

The facts

Issued
Feb 24, 2012, 9:49 AM CST (15:49 UTC)
Expired
Feb 24, 2012, 10:45 AM CST
In force
56 min
Issued by
the Storm Prediction Center
All 83 counties

Barbour County, AL, Bullock County, AL, Butler County, AL, Chambers County, AL, Coffee County, AL, Conecuh County, AL, Covington County, AL, Crenshaw County, AL, Dale County, AL, Elmore County, AL, Henry County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Monroe County, AL, Montgomery County, AL, Pike County, AL, Russell County, AL, Tallapoosa County, AL, Baldwin County, GA, Bibb County, GA, Bleckley County, GA, Burke County, GA, Butts County, GA, Calhoun County, GA, Candler County, GA, Chattahoochee County, GA, Clay County, GA, Columbia County, GA, Crawford County, GA, Crisp County, GA, Dodge County, GA, Dooly County, GA, Dougherty County, GA, Early County, GA, Emanuel County, GA, Glascock County, GA, Hancock County, GA, Harris County, GA, Houston County, GA, Jasper County, GA, Jefferson County, GA, Jenkins County, GA, Johnson County, GA, Jones County, GA, Lamar County, GA, Laurens County, GA, Lee County, GA, Macon County, GA, Marion County, GA, McDuffie County, GA, Meriwether County, GA, Monroe County, GA, Montgomery County, GA, Muscogee County, GA, Peach County, GA, Pike County, GA, Pulaski County, GA, Putnam County, GA, Quitman County, GA, Randolph County, GA, Richmond County, GA, Schley County, GA, Screven County, GA, Spalding County, GA, Stewart County, GA, Sumter County, GA, Talbot County, GA, Taylor County, GA, Terrell County, GA, Treutlen County, GA, Troup County, GA, Turner County, GA, Twiggs County, GA, Upson County, GA, Warren County, GA, Washington County, GA, Webster County, GA, Wheeler County, GA, Wilcox County, GA, Wilkinson County, GA, Worth County, GA, Aiken County, SC

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 12:00Z, 3.8 hours before the alert went out and 146 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 12:00Z on 2012-02-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1231 joules per kilogram.LCLEL10008507005003002001001 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 12:00Z on 2012-02-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 163 square meters per square second.1939587897117Sfc1 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
1231 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
542 m above ground
0-6 km bulk shear
83 kt
0-1 km storm-relative helicity
163 m²/s²
0-3 km storm-relative helicity
306 m²/s²
Significant tornado parameter
1.3
Supercell composite
4.7

Open this sounding in Storm Lab

The text

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

213 
ACUS11 KWNS 241550
SWOMCD
SPC MCD 241549
SCZ000-GAZ000-ALZ000-241645-

MESOSCALE DISCUSSION 0153
NWS STORM PREDICTION CENTER NORMAN OK
0949 AM CST FRI FEB 24 2012

AREAS AFFECTED...SRN AL...GA...WCNTRL SC

CONCERNING...TORNADO WATCH 35...

VALID 241549Z - 241645Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 35 CONTINUES.

A NARROW ZONE OF STRONGER BOUNDARY LAYER HEATING...ROUGHLY 50-75MI
WIDE...HAS DEVELOPED FROM THE WRN FL PANHANDLE...NEWD INTO CNTRL GA
BENEATH BREAKS IN CLOUD COVER.  LOW LEVEL LAPSE RATES ARE STEEPENING
ALONG THIS CORRIDOR THOUGH LOWER TROPOSPHERIC FLOW HAS VEERED
SOMEWHAT.  THIS HEATING WILL LIKELY TRANSLATE INTO A MORE UNSTABLE
ENVIRONMENT FOR INTENSE UPDRAFTS.

LATEST TRENDS SUGGEST CONVECTION IS BEGINNING TO INCREASE IN
INTENSITY ALONG THE SURGING COLD FRONT AS IT CATCHES UP TO THE
PRE-FRONTAL CONVECTION OVER AL.  ENHANCED CONVERGENCE COULD EASILY
ENCOURAGE STRENGTHENING AND THERE IS INCREASING CONFIDENCE THAT
SEVERE THUNDERSTORMS WILL OVERSPREAD THE AFOREMENTIONED CORRIDOR OF
STRONGER HEATING.  IT/S NOT ENTIRELY CLEAR HOW THE BAND OF
SHOWERS/ISOLATED THUNDERSTORMS WELL AHEAD OF THE FRONT OVER THE FL
PANHANDLE WILL EVOLVE.  LATEST THINKING IS CONVECTION WILL LIKELY BE
MORE CONCENTRATED/INTENSE ALONG THE SURGING COLD FRONT.

..DARROW.. 02/24/2012

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

ATTN...WFO...CHS...CAE...FFC...TAE...BMX...MOB...

LAT...LON   31448775 33128550 33708162 32648132 31388418 31048644
            31448775

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 24, 5:56 AM CSTMesoscale DiscussionSPCAutauga, Barbour, Bibb, Bullock, Calhoun, Chambers and 20 more94 min
Feb 24, 7:48 AM CSTTornado WatchSPCAutauga, Baldwin, Barbour, Bullock, Butler, Chambers and 25 more7 hr
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 DiscussionSPCCherokee, York25 min
Feb 24, 10:10 AM CSTMesoscale DiscussionSPCBamberg, Barnwell, Calhoun, Clarendon, Darlington, Dillon and 11 more65 min
Feb 24, 11:43 AM CSTMesoscale DiscussionSPCDarlington, Dillon, Florence, Georgetown, Horry, Marion and 2 more92 min
Feb 24, 12:19 PM CSTTornado WatchSPCDarlington, Dillon, Florence, Georgetown, Horry, Marion and 2 more7 hr
Feb 24, 3:45 PM CSTMesoscale DiscussionSPCDarlington, Dillon, Florence, Georgetown, Horry, Marion and 2 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.