Alert archive / Georgia / Mesoscale Discussions in 2012
Mesoscale Discussion 1674
The Storm Prediction Center issued this mesoscale discussion at Aug 1, 2012, 4:51 PM EDT for 64 counties in Georgia. It was in force for 54 min.
The area
The outline as issued.
The facts
- Issued
- Aug 1, 2012, 4:51 PM EDT (20:51 UTC)
- Expired
- Aug 1, 2012, 5:45 PM EDT
- In force
- 54 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
All 64 counties
Baldwin County, GA, Banks County, GA, Barrow County, GA, Bartow County, GA, Bibb County, GA, Butts County, GA, Carroll County, GA, Chattooga County, GA, Cherokee County, GA, Clarke County, GA, Clayton County, GA, Cobb County, GA, Coweta County, GA, Crawford County, GA, Dawson County, GA, DeKalb County, GA, Douglas County, GA, Elbert County, GA, Fannin County, GA, Fayette County, GA, Floyd County, GA, Forsyth County, GA, Franklin County, GA, Fulton County, GA, Gilmer County, GA, Gordon County, GA, Greene County, GA, Gwinnett County, GA, Habersham County, GA, Hall County, GA, Hancock County, GA, Haralson County, GA, Henry County, GA, Jackson County, GA, Jasper County, GA, Jones County, GA, Lamar County, GA, Lumpkin County, GA, Madison County, GA, Meriwether County, GA, Monroe County, GA, Morgan County, GA, Murray County, GA, Newton County, GA, Oconee County, GA, Oglethorpe County, GA, Paulding County, GA, Peach County, GA, Pickens County, GA, Pike County, GA, Polk County, GA, Putnam County, GA, Rockdale County, GA, Spalding County, GA, Stephens County, GA, Talbot County, GA, Taliaferro County, GA, Twiggs County, GA, Union County, GA, Upson County, GA, Walton County, GA, White County, GA, Whitfield County, GA, Wilkinson County, GA
The radar
The Atlanta radar (KFFC), 77 km from the middle of the area, began a volume at 20:51 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 12:00Z, 8.9 hours before the alert went out and 73 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
- 1144 J/kg
- Mixed-layer CIN
- -68 J/kg
- Mixed-layer LCL
- 595 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 59 m²/s²
- 0-3 km storm-relative helicity
- 97 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 2.5
The text
As transmitted, in the capitals the NWS used until 2016.
860
ACUS11 KWNS 012052
SWOMCD
SPC MCD 012051
GAZ000-012145-
MESOSCALE DISCUSSION 1674
NWS STORM PREDICTION CENTER NORMAN OK
0351 PM CDT WED AUG 01 2012
AREAS AFFECTED...NRN GA
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 012051Z - 012145Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...AN ISOLATED DMGG WIND AND HAIL THREAT WILL EXIST THIS
AFTERNOON ACROSS NRN GA. IN THE SHORT TERM...COVERAGE APPEARS TO
REMAIN TOO ISOLATED TO WARRANT WW ISSUANCE ATTM...BUT CONVECTIVE
TRENDS WILL CONTINUE TO BE MONITORED.
DISCUSSION...ISOLATED TSTMS HAVE DEVELOPED WITHIN THE PAST COUPLE
HRS OVER THE HIGHER TERRAIN OF NRN GA...BUT COVERAGE APPEARS TO BE
SOMEWHAT LIMITED BY WEAK MIDLEVEL RIDGING AND LACK OF APPARENT
MESOSCALE BOUNDARIES. A HOT AND MOIST BOUNDARY LAYER EXISTS
DOWNSTREAM FROM ONGOING CONVECTION...YIELDING MLCAPE VALUES AOA 2000
J/KG. ADDITIONAL CONVECTIVE DEVELOPMENT THROUGH THE NEXT FEW HRS
SHOULD PRIMARILY BE DRIVEN BY STORM-SCALE BOUNDARY INTERACTIONS AND
CONVECTIVE MERGERS. A FAVORABLE ENVIRONMENT EXISTS FOR STRONG-SVR
WIND GUSTS...GIVEN THE PRESENCE OF STEEP LOW-LEVEL LAPSE RATES AND
DCAPE VALUES AOA 1200 J/KG. STORM ORGANIZATION MAY BE SOMEWHAT
LIMITED WITH MIDLEVEL FLOW SAMPLED NEAR 20 KTS PER REGIONAL VWP
DATA. ADDITIONALLY...A HAIL THREAT COULD ACCOMPANY THE STRONGEST
CONVECTIVE CORES.
IT IS UNCLEAR WHETHER UPSTREAM CONVECTION /I.E. OVER ERN TN AND FAR
WRN NC/ ACCOMPANYING A WEAK CNTRL APPALACHIANS UPPER IMPULSE WILL BE
MAINTAINED INTO PARTS OF NRN GA PRIOR TO DIURNAL COOLING
COMMENCEMENT...BUT AN ADDITIONAL /PERHAPS MORE ORGANIZED/ SVR THREAT
MAY EVENTUALLY DEVELOP LATER THIS AFTERNOON/EVENING.
..ROGERS/CARBIN.. 08/01/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...GSP...FFC...
LAT...LON 34238282 33328280 32558314 32498390 32718478 33618529
34138541 34518541 34808514 34968451 34938389 34748355
34238282Nearby
Mesoscale Discussions in Georgia, 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.