Alert archive / Alabama / Severe Thunderstorm Watches in 2004
Severe Thunderstorm Watch 767
The Storm Prediction Center issued this severe thunderstorm watch at Aug 20, 2004, 1:35 PM CDT for 22 counties in Alabama; 17 counties in Tennessee. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 20, 2004, 1:35 PM CDT (18:35 UTC)
- Expired
- Aug 20, 2004, 7:00 PM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
All 39 counties
Blount County, AL, Calhoun County, AL, Colbert County, AL, Cullman County, AL, DeKalb County, AL, Etowah County, AL, Fayette County, AL, Franklin County, AL, Jackson County, AL, Jefferson County, AL, Lamar County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Marion County, AL, Marshall County, AL, Morgan County, AL, St. Clair County, AL, Talladega County, AL, Walker County, AL, Winston County, AL, Bedford County, TN, Cannon County, TN, Coffee County, TN, Franklin County, TN, Giles County, TN, Grundy County, TN, Hickman County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Marion County, TN, Marshall County, TN, Maury County, TN, Moore County, TN, Perry County, TN, Warren County, TN, Wayne County, TN
The radar
The Columbus AFB radar (KGWX), 115 km from the middle of the area, began a volume at 18:39 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
15 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 20, 1:50 PM CDT | Severe Thunderstorm Warning | BMX | Marion | 40 min |
| Aug 20, 1:56 PM CDT | Severe Thunderstorm Warning | HUN | Colbert, Franklin | 49 min |
| Aug 20, 1:57 PM CDT | Severe Thunderstorm Warning | BMX | Lamar | 48 min |
| Aug 20, 2:48 PM CDT | Severe Thunderstorm Warning | HUN | Colbert, Lauderdale | 42 min |
| Aug 20, 3:08 PM CDT | Tornado Warning | HUN | Jackson | 37 min |
| Aug 20, 3:13 PM CDT | Severe Thunderstorm Warning | HUN | Madison | 32 min |
| Aug 20, 3:23 PM CDT | Severe Thunderstorm Warning | HUN | Lincoln, Moore | 27 min |
| Aug 20, 3:28 PM CDT | Tornado Warning | HUN | Jackson | 32 min |
| Aug 20, 3:30 PM CDT | Severe Thunderstorm Warning | MRX | Marion | 45 min |
| Aug 20, 3:36 PM CDT | Tornado Warning | HUN | Moore | 44 min |
| Aug 20, 3:45 PM CDT | Severe Thunderstorm Warning | OHX | Coffee | 30 min |
| Aug 20, 4:03 PM CDT | Severe Thunderstorm Warning | HUN | Jackson | 42 min |
| Aug 20, 4:14 PM CDT | Tornado Warning | HUN | Jackson | 31 min |
| Aug 20, 4:30 PM CDT | Flash Flood Warning | MRX | Marion | 2 hr |
| Aug 20, 4:45 PM CDT | Severe Thunderstorm Warning | HUN | DeKalb, Jackson | 45 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
Birmingham, AL (KBMX), launched 12:00Z, 6.6 hours before the alert went out and 131 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
- 591 J/kg
- Mixed-layer CIN
- -67 J/kg
- Mixed-layer LCL
- 915 m above ground
- 0-6 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- 15 m²/s²
- 0-3 km storm-relative helicity
- 46 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, 3:35 PM CDT | Mesoscale Discussion | SPC | Cherokee, Cleburne | 85 min |
| Aug 20, 3:55 PM CDT | Severe Thunderstorm Watch | SPC | Cherokee, Clay, Cleburne, Randolph | 5 hr |
| 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 Alabama, 2004Severe Thunderstorm Watches in Tennessee, 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.