Alert archive / Georgia / Severe Thunderstorm Watches in 2004
Severe Thunderstorm Watch 770
The Storm Prediction Center issued this severe thunderstorm watch at Aug 20, 2004, 3:55 PM CDT for 4 states. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 20, 2004, 3:55 PM CDT (20:55 UTC)
- Expired
- Aug 20, 2004, 9:00 PM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
All 60 counties
Cherokee County, AL, Clay County, AL, Cleburne County, AL, Randolph County, AL, Bartow County, GA, Carroll County, GA, Catoosa County, GA, Chattooga County, GA, Cherokee County, GA, Clayton County, GA, Cobb County, GA, Coweta County, GA, Dawson County, GA, DeKalb County, GA, Douglas County, GA, Fannin County, GA, Fayette County, GA, Floyd County, GA, Forsyth County, GA, Fulton County, GA, Gilmer County, GA, Gordon County, GA, Gwinnett County, GA, Hall County, GA, Haralson County, GA, Heard County, GA, Henry County, GA, Lumpkin County, GA, Meriwether County, GA, Murray County, GA, Paulding County, GA, Pickens County, GA, Pike County, GA, Polk County, GA, Spalding County, GA, Towns County, GA, Troup County, GA, Union County, GA, Walker County, GA, White County, GA, Whitfield County, GA, Cherokee County, NC, Clay County, NC, Graham County, NC, Swain County, NC, Anderson County, TN, Blount County, TN, Bradley County, TN, Hamilton County, TN, Jefferson County, TN, Knox County, TN, Loudon County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Morgan County, TN, Polk County, TN, Rhea County, TN, Roane County, TN, Sevier County, TN
The radar
The Atlanta radar (KFFC), 106 km from the middle of the area, began a volume at 20:56 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.
Warnings issued inside it
11 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 20, 4:57 PM CDT | Severe Thunderstorm Warning | MRX | Hamilton | 48 min |
| Aug 20, 5:04 PM CDT | Severe Thunderstorm Warning | FFC | Whitfield | 26 min |
| Aug 20, 5:19 PM CDT | Severe Thunderstorm Warning | MRX | Bradley | 56 min |
| Aug 20, 5:27 PM CDT | Severe Thunderstorm Warning | FFC | Murray | 33 min |
| Aug 20, 5:36 PM CDT | Severe Thunderstorm Warning | FFC | Walker | 39 min |
| Aug 20, 6:01 PM CDT | Severe Thunderstorm Warning | FFC | Gordon, Murray | 44 min |
| Aug 20, 7:29 PM CDT | Severe Thunderstorm Warning | FFC | Hall | 31 min |
| Aug 20, 7:38 PM CDT | Severe Thunderstorm Warning | FFC | Lumpkin | 37 min |
| Aug 20, 7:41 PM CDT | Severe Thunderstorm Warning | FFC | White | 34 min |
| Aug 20, 7:44 PM CDT | Severe Thunderstorm Warning | FFC | Union | 31 min |
| Aug 20, 7:54 PM CDT | Severe Thunderstorm Warning | FFC | Towns | 36 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 8.9 hours before the alert went out and 107 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
- 12 J/kg
- Mixed-layer CIN
- -210 J/kg
- Mixed-layer LCL
- 1267 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- 34 m²/s²
- 0-3 km storm-relative helicity
- 51 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 20, 12:39 PM CDT | Mesoscale Discussion | SPC | Colbert, Cullman, Fayette, Franklin, Jackson, Lamar and 8 more | 2 hr |
| Aug 20, 1:35 PM CDT | Severe Thunderstorm Watch | SPC | Blount, Calhoun, Colbert, Cullman, DeKalb, Etowah and 16 more | 5 hr |
| Aug 20, 3:35 PM CDT | Mesoscale Discussion | SPC | Cherokee, Cleburne | 85 min |
| Aug 20, 5:48 PM CDT | Mesoscale Discussion | SPC | Calhoun, Cherokee, Cleburne, DeKalb, Etowah, Randolph and 2 more | 57 min |
Nearby
Severe Thunderstorm Watches in Georgia, 2004Severe Thunderstorm Watches in Tennessee, 2004Severe Thunderstorm Watches in Alabama, 2004Every severe thunderstorm watch in 2004
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.