Alert archive / Georgia / Mesoscale Discussions in 2012
Mesoscale Discussion 1867
The Storm Prediction Center issued this mesoscale discussion at Sep 2, 2012, 8:43 PM CDT for 4 states. It was in force for 62 min.
The area
The outline as issued.
The facts
- Issued
- Sep 2, 2012, 8:43 PM CDT (01:43 UTC)
- Expired
- Sep 2, 2012, 9:45 PM CDT
- In force
- 62 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 610
All 34 counties
Calhoun County, AL, Cherokee County, AL, Cleburne County, AL, DeKalb County, AL, Etowah County, AL, St. Clair County, AL, Bartow County, GA, Carroll County, GA, Catoosa County, GA, Chattooga County, GA, Dade County, GA, Fannin County, GA, Floyd County, GA, Gilmer County, GA, Gordon County, GA, Haralson County, GA, Murray County, GA, Paulding County, GA, Pickens County, GA, Polk County, GA, Walker County, GA, Whitfield County, GA, Cherokee County, NC, Graham County, NC, Bledsoe County, TN, Bradley County, TN, Hamilton County, TN, Marion County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Polk County, TN, Rhea County, TN, Sequatchie County, TN
The radar
The Northeast Alabama radar (KHTX), 83 km from the middle of the area, began a volume at 01:42 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, 1.7 hours before the alert went out and 144 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
- 1453 J/kg
- Mixed-layer CIN
- -16 J/kg
- Mixed-layer LCL
- 1105 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 50 m²/s²
- 0-3 km storm-relative helicity
- 76 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
800 ACUS11 KWNS 030143 SWOMCD SPC MCD 030143 NCZ000-TNZ000-GAZ000-ALZ000-030245- MESOSCALE DISCUSSION 1867 NWS STORM PREDICTION CENTER NORMAN OK 0843 PM CDT SUN SEP 02 2012 AREAS AFFECTED...NERN AL...NWRN GA...SERN TN CONCERNING...SEVERE THUNDERSTORM WATCH 610... VALID 030143Z - 030245Z THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 610 CONTINUES. SUMMARY...THE SEVERE THREAT ACROSS WW 610 IS EXPECTED TO PERSIST FOR THE NEXT HOUR OR TWO BEFORE GRADUALLY DIMINISHING AS INSTABILITY WANES AND THE CURRENT LINE OF STORMS MOVES THROUGH. DISCUSSION...THE OVERALL CHANCE FOR SEVERE GUSTS IS WANING AS THE LOSS OF DAYTIME HEATING CONTINUES TO COOL/DECOUPLE THE BOUNDARY LAYER. HOWEVER...LATEST RADAR TRENDS HAVE SHOWN SOME INTENSIFICATION/BOWING SEGMENTS IN A FEW OF THE CONVECTIVE CLUSTERS ACROSS NWRN GA AND SWRN TN. AS SUCH...THERE IS A SLIGHT CHANCE OF A FEW SEVERE GUSTS DURING THE NEXT HOUR OR TWO BEFORE THE ACTIVITY DIMINISHES. IN ADDITION TO THE SEVERE THREAT...A MOIST ATMOSPHERIC PROFILE /PWATS OVER 1.75 INCHES ON BOTH THE BMX AND FFC 00Z SOUNDINGS/ WILL SUPPORT A HEAVY RAIN THREAT AND POSSIBLE FLASH FLOODING WITH RAIN RATES OVER 2 INCHES PER HOUR POSSIBLE. THE HEAVY RAIN THREAT APPEARS GREATEST ACROSS NERN AL AND NWRN GA WHERE A STRATIFORM RAIN REGION IS CURRENTLY LOCATED AND MORE RAIN EXISTS UPSTREAM. ..MOSIER.. 09/03/2012 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC...BMX...HUN... LAT...LON 33578670 35638531 35638355 33588497 33578670
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 2, 7:13 PM CDT | Mesoscale Discussion | SPC | Colbert, Fayette, Franklin, Lamar, Lauderdale, Lawrence and 3 more | 62 min |
| Sep 2, 9:48 PM CDT | Mesoscale Discussion | SPC | Fayette, Lamar, Marion, Walker, Winston | 57 min |
| Sep 3, 12:29 PM CDT | Mesoscale Discussion | SPC | Barbour, Bullock, Butler, Clarke, Coffee, Conecuh and 11 more | 61 min |
| Sep 3, 3:25 PM CDT | Mesoscale Discussion | SPC | Autauga, Barbour, Bibb, Bullock, Butler, Chilton and 16 more | 65 min |
| Sep 3, 3:46 PM CDT | Tornado Watch | SPC | Autauga, Bibb, Butler, Chilton, Choctaw, Clarke and 19 more | 7 hr |
| Sep 3, 6:55 PM CDT | Mesoscale Discussion | SPC | Autauga, Bibb, Butler, Chilton, Choctaw, Clarke and 19 more | 65 min |
| Sep 3, 12:52 PM CDT | Mesoscale Discussion | SPC | Alamance, Anson, Cabarrus, Caswell, Chatham, Cumberland and 19 more | 53 min |
Nearby
Mesoscale Discussions in Georgia, 2012Mesoscale Discussions in Tennessee, 2012Mesoscale Discussions in Alabama, 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.