Alert archive / Georgia / Mesoscale Discussions in 2012

Mesoscale Discussion 2014

October 1, 201219 counties in Alabama; 11 counties in Florida; 74 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Oct 1, 2012, 12:52 PM CDT for 19 counties in Alabama; 11 counties in Florida; 74 counties in Georgia. It was in force for 53 min.

The area

The outline as issued.

The facts

Issued
Oct 1, 2012, 12:52 PM CDT (17:52 UTC)
Expired
Oct 1, 2012, 1:45 PM CDT
In force
53 min
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 104 counties

Barbour County, AL, Blount County, AL, Calhoun County, AL, Chambers County, AL, Cherokee County, AL, Clay County, AL, Cleburne County, AL, Etowah County, AL, Henry County, AL, Houston County, AL, Jefferson County, AL, Lee County, AL, Marshall County, AL, Randolph County, AL, Russell County, AL, Shelby County, AL, St. Clair County, AL, Talladega County, AL, Tallapoosa County, AL, Bay County, FL, Calhoun County, FL, Franklin County, FL, Gadsden County, FL, Gulf County, FL, Jackson County, FL, Jefferson County, FL, Leon County, FL, Liberty County, FL, Madison County, FL, Wakulla County, FL, Baker County, GA, Bartow County, GA, Bibb County, GA, Bleckley County, GA, Brooks County, GA, Butts County, GA, Calhoun County, GA, Carroll County, GA, Chattahoochee County, GA, Cherokee County, GA, Clay County, GA, Clayton County, GA, Cobb County, GA, Colquitt County, GA, Cook County, GA, Coweta County, GA, Crawford County, GA, Crisp County, GA, Decatur County, GA, DeKalb County, GA, Dooly County, GA, Dougherty County, GA, Douglas County, GA, Early County, GA, Fayette County, GA, Floyd County, GA, Fulton County, GA, Grady County, GA, Gwinnett County, GA, Haralson County, GA, Harris County, GA, Heard County, GA, Henry County, GA, Houston County, GA, Irwin County, GA, Jasper County, GA, Jones County, GA, Lamar County, GA, Lee County, GA, Macon County, GA, Marion County, GA, Meriwether County, GA, Miller County, GA, Mitchell County, GA, Monroe County, GA, Morgan County, GA, Muscogee County, GA, Newton County, GA, Paulding County, GA, Peach County, GA, Pike County, GA, Polk County, GA, Pulaski County, GA, Quitman County, GA, Randolph County, GA, Rockdale County, GA, Schley County, GA, Seminole County, GA, Spalding County, GA, Stewart County, GA, Sumter County, GA, Talbot County, GA, Taylor County, GA, Terrell County, GA, Thomas County, GA, Tift County, GA, Troup County, GA, Turner County, GA, Twiggs County, GA, Upson County, GA, Walton County, GA, Webster County, GA, Wilcox County, GA, Worth County, GA

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, 5.9 hours before the alert went out and 148 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 2012-10-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 512 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 12:00Z on 2012-10-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 240 square meters per square second.19395878Sfc1 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
512 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
479 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
240 m²/s²
0-3 km storm-relative helicity
301 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.5

Open this sounding in Storm Lab

The text

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

752 
ACUS11 KWNS 011753
SWOMCD
SPC MCD 011752
GAZ000-FLZ000-ALZ000-011845-

MESOSCALE DISCUSSION 2014
NWS STORM PREDICTION CENTER NORMAN OK
1252 PM CDT MON OCT 01 2012

AREAS AFFECTED...PORTIONS OF ERN AL...WRN GA...ERN FL PANHANDLE

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 011752Z - 011845Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...A LINE OF CONVECTION FROM W-CNTRL GA THROUGH EXTREME SE AL
INTO THE FL PANHANDLE HAS INCREASED IN STRENGTH OVER THE LAST HOUR.
FAVORABLE LOW LEVEL WINDS WILL LEAD TO AT LEAST A LOW THREAT OF A
FEW WEAK/BRIEF TORNADOES OR STRONG WIND GUSTS. FURTHER TO THE NORTH
AND WEST...THREAT MAY ALSO INCREASE SOON. BOTH AREAS ARE BEING
MONITORED FOR POTENTIAL TORNADO WATCH.

DISCUSSION...CONVECTION HAS INCREASED IN INTENSITY SLIGHTLY OVER THE
LAST HOUR OR SO. KEOX /FORT RUCKER/ AND KTLH RADARS HAVE SHOWN
SEVERAL TRANSIENT/WEAK CIRCULATIONS TRACKING TO THE NORTHEAST ACROSS
FAR SE AL/WRN FL PANHANDLE AND INTO FAR SW GA. BACKED SFC FLOW WITH
FAVORABLE VERTICALLY VEERING PROFILES WITH 0-1KM SRH NEAR 200 M2/S2
PER REGIONAL 88-D VWP/S WOULD INDICATE THAT AN INCREASE IN LOW LEVEL
CIRCULATIONS IS POSSIBLE GIVEN MODEST SFC HEATING/DESTABILIZATION
AHEAD OF LINE OF CURRENT CONVECTION. WHILE POOR LAPSE RATES AND
LIMITING FORCING FOR ASCENT WILL LIMIT WIDESPREAD STRONG/SEVERE
STORMS...AT LEAST LOW CHANCES FOR A FEW WEAK/BRIEF TORNADOES OR
LOCALLY STRONG WIND GUSTS WILL BE POSSIBLE.

THE THREAT MAY EXTEND TO THE NORTH AND WEST ACROSS PORTIONS OF NE
AL/NW GA CLOSER TO EWD PROGRESSING SFC LOW AND W-E ORIENTED WARM
FRONT. WHILE TEMPERATURES HERE REMAIN COOLER /LOW TO MID 70S/ DUE TO
EARLIER STORMS AND CLOUD COVER...BREAKS IN CLOUDINESS HAVE LEAD TO
WEAK DESTABILIZATION IN MOIST AIRMASS. BOTH OF THESE AREAS ARE BEING
MONITORED FOR TORNADO WATCH ISSUANCE.

..LEITMAN/GOSS.. 10/01/2012

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

ATTN...WFO...FFC...TAE...BMX...HUN...

LAT...LON   31098551 32278542 32688565 32978626 33288702 33808705
            34198683 34418609 34468519 34158413 33538342 32678332
            31958322 31248326 31058329 30238351 29818403 29488470
            29648529 30078569 31098551

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 30, 9:48 PM CDTMesoscale DiscussionSPCBaldwin, Choctaw, Clarke, Conecuh, Escambia, Mobile and 3 more87 min
Oct 1, 1:45 AM CDTMesoscale DiscussionSPCBaldwin, Coffee, Conecuh, Covington, Dale, Escambia and 5 more2 hr
Oct 1, 5:51 AM CDTMesoscale DiscussionSPCBarbour, Bullock, Calhoun, Chambers, Clay, Cleburne and 20 more114 min
Oct 1, 1:16 PM CDTTornado WatchSPCBlount, Bullock, Calhoun, Chambers, Cherokee, Clay and 19 more7 hr
Oct 1, 3:00 PM CDTMesoscale DiscussionSPCBlount, Calhoun, Chambers, Cherokee, Clay, Cleburne and 12 more2 hr
Oct 1, 5:40 PM CDTMesoscale DiscussionSPCChambers, Cherokee, Cleburne, Lee, Randolph95 min

Nearby

Mesoscale Discussions in Georgia, 2012Mesoscale Discussions in Alabama, 2012Mesoscale Discussions in Florida, 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.