Alert archive / Georgia / Mesoscale Discussions in 2021
Mesoscale Discussion 2082
The Storm Prediction Center issued this mesoscale discussion at Dec 29, 2021, 10:56 PM CST for 4 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Dec 29, 2021, 10:56 PM CST (04:56 UTC)
- Expired
- Dec 30, 2021, 1:00 AM CST
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 571
All 58 counties
Clay County, AL, Randolph County, AL, Banks County, GA, Barrow County, GA, Butts County, GA, Carroll County, GA, Clarke County, GA, Clayton County, GA, Coweta County, GA, DeKalb County, GA, Douglas County, GA, Elbert County, GA, Fayette County, GA, Franklin County, GA, Fulton County, GA, Greene County, GA, Gwinnett County, GA, Hall County, GA, Hart County, GA, Heard County, GA, Henry County, GA, Jackson County, GA, Jasper County, GA, Jones County, GA, Lamar County, GA, Madison County, GA, Meriwether County, GA, Monroe County, GA, Morgan County, GA, Newton County, GA, Oconee County, GA, Oglethorpe County, GA, Pike County, GA, Putnam County, GA, Rockdale County, GA, Spalding County, GA, Stephens County, GA, Taliaferro County, GA, Troup County, GA, Upson County, GA, Walton County, GA, Wilkes County, GA, Cleveland County, NC, Gaston County, NC, Henderson County, NC, Lincoln County, NC, Polk County, NC, Rutherford County, NC, Abbeville County, SC, Anderson County, SC, Cherokee County, SC, Greenville County, SC, Greenwood County, SC, Laurens County, SC, Oconee County, SC, Pickens County, SC, Spartanburg County, SC, Union County, SC
The radar
The Atlanta radar (KFFC), 102 km from the middle of the area, began a volume at 04:57 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 nearest sounding before it
Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 4.9 hours before the alert went out and 97 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.
- Mixed-layer CAPE
- 251 J/kg
- Mixed-layer CIN
- -52 J/kg
- Mixed-layer LCL
- 790 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 228 m²/s²
- 0-3 km storm-relative helicity
- 240 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 3.0
The text
As transmitted.
992
ACUS11 KWNS 300456
SWOMCD
SPC MCD 300456
NCZ000-SCZ000-GAZ000-ALZ000-300700-
Mesoscale Discussion 2082
NWS Storm Prediction Center Norman OK
1056 PM CST Wed Dec 29 2021
Areas affected...east-central Alabama into northern Georgia and the
far western Carolinas
Concerning...Tornado Watch 571...
Valid 300456Z - 300700Z
The severe weather threat for Tornado Watch 571 continues.
SUMMARY...Isolated reports of damaging gusts or a brief tornado
remain possible across the watch area as a line of storms pushes
east tonight.
DISCUSSION...A line of storms currently stretches from northwestern
SC across northern GA and into central AL, where a lone supercell
produced a tornado earlier. Northern portions of the outflow are
mainly producing rain showers into western NC, but an uptick in
intensity with this portion of the line cannot be ruled out as it
intercepts lower 60s F dewpoints.
To the southwest, the strongest portion of the line continues to
move across northern GA with relatively laminar outflow currently.
The orientation of this line is becoming more parallel with the
deep-layer shear, which is not particularly favorable for for
forward acceleration. However, shear remains favorable for
supercells, and a brief QLCS tornado remains possible along the
line. The greatest instability will remain farther west into AL,
with MLCAPE over 1000 J/kg, with around 250 m2/s2 effective SRH
still favoring supercells.
..Jewell.. 12/30/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...CAE...GSP...FFC...BMX...
LAT...LON 33078664 33508553 33958450 34478369 35088296 35508247
35608122 35348094 34908123 34248196 33458300 32948348
32888425 32938558 32958620 33078664SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 29, 7:27 PM CST | Mesoscale Discussion | SPC | Bibb, Blount, Calhoun, Cherokee, Chilton, Clay and 15 more | 2 hr |
| Dec 29, 8:44 PM CST | Mesoscale Discussion | SPC | Calhoun, Cherokee, Etowah | 2 hr |
| Dec 29, 9:16 PM CST | Tornado Watch | SPC | Calhoun, Chambers, Chilton, Clay, Cleburne, Coosa and 4 more | 7 hr |
| Dec 30, 1:15 AM CST | Mesoscale Discussion | SPC | Bibb, Chambers, Chilton, Clay, Coosa, Randolph and 3 more | 90 min |
| Dec 30, 4:02 AM CST | Mesoscale Discussion | SPC | Bibb, Chambers, Chilton, Clay, Coosa, Greene and 10 more | 2 hr |
| Dec 30, 10:34 AM CST | Mesoscale Discussion | SPC | Autauga, Bullock, Chambers, Chilton, Coosa, Dallas and 9 more | 116 min |
| Dec 30, 1:05 PM CST | Severe Thunderstorm Watch | SPC | Autauga, Barbour, Bullock, Butler, Chambers, Clarke and 13 more | 7 hr |
| Dec 30, 2:54 PM CST | Mesoscale Discussion | SPC | Barbour, Bullock, Crenshaw, Lee, Lowndes, Macon and 3 more | 2 hr |
| Dec 30, 1:00 PM CST | Mesoscale Discussion | SPC | Appling, Atkinson, Bacon, Baker, Ben Hill, Berrien and 29 more | 2 hr |
| Dec 30, 5:35 PM CST | Mesoscale Discussion | SPC | Appling, Atkinson, Bacon, Ben Hill, Berrien, Brantley and 32 more | 115 min |
Nearby
Mesoscale Discussions in Georgia, 2021Mesoscale Discussions in South Carolina, 2021Mesoscale Discussions in North Carolina, 2021Every mesoscale discussion in 2021
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.