Alert archive / Georgia / Mesoscale Discussions in 2012

Mesoscale Discussion 459

April 5, 201217 counties in Alabama; 9 counties in Florida; 36 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Apr 5, 2012, 1:12 PM CDT for 17 counties in Alabama; 9 counties in Florida; 36 counties in Georgia. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
Apr 5, 2012, 1:12 PM CDT (18:12 UTC)
Expired
Apr 5, 2012, 2:45 PM CDT
In force
93 min
Issued by
the Storm Prediction Center
All 62 counties

Barbour County, AL, Bullock County, AL, Chambers County, AL, Clay County, AL, Coffee County, AL, Covington County, AL, Crenshaw County, AL, Dale County, AL, Geneva County, AL, Henry County, AL, Houston County, AL, Lee County, AL, Macon County, AL, Pike County, AL, Randolph County, AL, Russell County, AL, Tallapoosa County, AL, Calhoun County, FL, Gadsden County, FL, Holmes County, FL, Jackson County, FL, Liberty County, FL, Okaloosa County, FL, Santa Rosa County, FL, Walton County, FL, Washington County, FL, Baker County, GA, Calhoun County, GA, Chattahoochee County, GA, Clay County, GA, Coweta County, GA, Crawford County, GA, Crisp County, GA, Decatur County, GA, Dooly County, GA, Dougherty County, GA, Early County, GA, Grady County, GA, Harris County, GA, Heard County, GA, Houston County, GA, Lee County, GA, Macon County, GA, Marion County, GA, Meriwether County, GA, Miller County, GA, Mitchell County, GA, Muscogee County, GA, Peach County, GA, Pike County, GA, Quitman County, GA, Randolph County, GA, Schley County, GA, Seminole County, GA, Stewart County, GA, Sumter County, GA, Talbot County, GA, Taylor County, GA, Terrell County, GA, Troup County, GA, Upson County, GA, Webster 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

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 6.2 hours before the alert went out and 190 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, Tallahassee Rgnl, FL at 12:00Z on 2012-04-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 71 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, Tallahassee Rgnl, FL at 12:00Z on 2012-04-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 59 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
71 J/kg
Mixed-layer CIN
-397 J/kg
Mixed-layer LCL
1087 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
59 m²/s²
0-3 km storm-relative helicity
61 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.

858 
ACUS11 KWNS 051813
SWOMCD
SPC MCD 051812
GAZ000-FLZ000-ALZ000-051945-

MESOSCALE DISCUSSION 0459
NWS STORM PREDICTION CENTER NORMAN OK
0112 PM CDT THU APR 05 2012

AREAS AFFECTED...E CNTRL/SRN AL...W CNTRL/SW GA AND THE FL PNHDL

CONCERNING...SEVERE THUNDERSTORM WATCH 143...

VALID 051812Z - 051945Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 143
CONTINUES.

A NEW WW MAY BE NEEDED EAST OF WW 143...ACROSS PARTS OF GEORGIA AND
NORTHERN FLORIDA...WITHIN THE NEXT HOUR OR TWO.

THE LOWER/MID TROPOSPHERIC CYCLONIC CIRCULATION...ASSOCIATED WITH
THE MESOSCALE CONVECTIVE SYSTEM NOW SPREADING ACROSS/EAST OF
BIRMINGHAM/MONTGOMERY AND ADJACENT AREAS OF CENTRAL/SOUTHERN
ALABAMA...IS MIGRATING EASTWARD AROUND 35 KTS.  THIS FEATURE APPEARS
LIKELY TO PROGRESS ACROSS EAST CENTRAL ALABAMA INTO WEST CENTRAL
GEORGIA...NORTH OF COLUMBUS...BETWEEN NOW AND 20-21Z... AND SHOULD
MAINTAIN VIGOROUS CONVECTIVE DEVELOPMENT IN THE PRESENCE OF WEAK TO
MODERATE CAPE AND STRONG DEEP LAYER SHEAR.  WITH THE WEAK AND
WESTERLY COMPONENT TO THE LOW-LEVEL WIND FIELDS ...IN ADDITION TO
TEMPERED BOUNDARY LAYER WARMING...REMAINING A LIMITING FACTOR TO A
MORE SUBSTANTIVE SEVERE WEATHER THREAT...IT IS NOT CERTAIN THAT
THERE WILL BE MUCH INTENSIFICATION IN THE NEAR TERM.
HOWEVER...PERIODIC STRONGER UPDRAFT PULSES PROBABLY WILL REMAIN
CAPABLE OF PRODUCING SEVERE HAIL...AND THE RISK FOR AT LEAST
LOCALIZED CONVECTIVELY ENHANCED SURFACE WIND GUSTS WILL CONTINUE.

..KERR.. 04/05/2012

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

ATTN...WFO...FFC...TAE...BMX...MOB...

LAT...LON   31308688 32078619 32728590 33428606 33428478 32488357
            30828408 30258471 30248521 30638728 31308688

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 5, 7:36 AM CDTMesoscale DiscussionSPCChoctaw, Greene, Hale, Marengo, Perry, Pickens and 2 more54 min
Apr 5, 9:14 AM CDTSevere Thunderstorm WatchSPCAutauga, Barbour, Bibb, Bullock, Butler, Chambers and 34 more8 hr
Apr 5, 10:41 AM CDTMesoscale DiscussionSPCAutauga, Bibb, Butler, Chilton, Choctaw, Clarke and 15 more94 min
Apr 5, 12:09 PM CDTMesoscale DiscussionSPCColbert, Cullman, Franklin, Lauderdale, Lawrence, Limestone and 4 more96 min
Apr 5, 1:21 PM CDTSevere Thunderstorm WatchSPCColbert, DeKalb, Franklin, Jackson, Lauderdale, Lawrence and 4 more8 hr
Apr 5, 1:58 PM CDTSevere Thunderstorm WatchSPCCoffee, Dale, Geneva, Henry, Houston6 hr
Apr 5, 3:06 PM CDTMesoscale DiscussionSPCColbert, DeKalb, Franklin, Jackson, Lauderdale, Lawrence and 4 more54 min
Apr 5, 3:46 PM CDTMesoscale DiscussionSPCBlount, Calhoun, Cullman, Etowah, Fayette, Jefferson and 7 more59 min
Apr 5, 3:49 PM CDTMesoscale DiscussionSPCGeneva, Henry, Houston86 min
Apr 5, 6:14 PM CDTSevere Thunderstorm WatchSPCAutauga, Bibb, Blount, Bullock, Calhoun, Chambers and 21 more3 hr
Apr 5, 6:15 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Blount, Bullock, Calhoun, Chambers and 23 more45 min
Apr 4, 9:03 PM CDTMesoscale DiscussionSPCCharlotte, Collier, DeSoto, Hillsborough, Lee, Manatee and 2 more57 min
Apr 5, 1:10 AM CDTMesoscale DiscussionSPCMiami-Dade, Monroe3 hr
Apr 5, 12:03 PM CDTMesoscale DiscussionSPCBanks, Burke, Clarke, Columbia, Effingham, Elbert and 24 more87 min
Apr 5, 12:47 PM CDTSevere Thunderstorm WatchSPCBryan, Bulloch, Burke, Candler, Chatham, Columbia and 17 more7 hr
Apr 5, 12:54 PM CDTMesoscale DiscussionSPCBartow, Catoosa, Chattooga, Cherokee, Dade, Dawson and 11 more96 min
Apr 5, 2:37 PM CDTMesoscale DiscussionSPCBurke, Chatham, Columbia, Effingham, Elbert, Franklin and 11 more53 min
Apr 5, 5:35 PM CDTMesoscale DiscussionSPCBryan, Bulloch, Burke, Candler, Chatham, Columbia and 12 more85 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.