Alert archive / Alabama / Severe Thunderstorm Watches in 2003
Severe Thunderstorm Watch 793
The Storm Prediction Center issued this severe thunderstorm watch at Jul 21, 2003, 6:00 PM CDT for 24 counties in Alabama; Carroll County, Heard County, Georgia. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 21, 2003, 6:00 PM CDT (23:00 UTC)
- Expired
- Jul 21, 2003, 11:00 PM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
All 26 counties
Autauga County, AL, Bibb County, AL, Calhoun County, AL, Chambers County, AL, Chilton County, AL, Choctaw County, AL, Clay County, AL, Cleburne County, AL, Coosa County, AL, Dallas County, AL, Elmore County, AL, Hale County, AL, Jefferson County, AL, Lowndes County, AL, Macon County, AL, Marengo County, AL, Montgomery County, AL, Perry County, AL, Randolph County, AL, Shelby County, AL, St. Clair County, AL, Talladega County, AL, Tallapoosa County, AL, Wilcox County, AL, Carroll County, GA, Heard County, GA
The radar
The Birmingham radar (KBMX), 56 km from the middle of the area, began a volume at 23:00 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
6 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 6:00 PM CDT | Severe Thunderstorm Warning | BMX | Shelby | 30 min |
| Jul 21, 6:03 PM CDT | Severe Thunderstorm Warning | BMX | Chilton, Marengo | 57 min |
| Jul 21, 6:11 PM CDT | Severe Thunderstorm Warning | BMX | Perry | 64 min |
| Jul 21, 6:35 PM CDT | Severe Thunderstorm Warning | BMX | Cleburne | 25 min |
| Jul 21, 7:03 PM CDT | Severe Thunderstorm Warning | BMX | Dallas | 57 min |
| Jul 21, 7:14 PM CDT | Severe Thunderstorm Warning | BMX | Perry | 46 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, 11.0 hours before the alert went out and 57 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
- 2335 J/kg
- Mixed-layer CIN
- -14 J/kg
- Mixed-layer LCL
- 677 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- 2 m²/s²
- 0-3 km storm-relative helicity
- 28 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 |
|---|---|---|---|---|
| Jul 21, 1:10 PM CDT | Mesoscale Discussion | SPC | Blount, Colbert, Cullman, DeKalb, Etowah, Franklin and 9 more | 95 min |
| Jul 21, 1:45 PM CDT | Severe Thunderstorm Watch | SPC | Blount, Cherokee, Colbert, Cullman, DeKalb, Etowah and 13 more | 5 hr |
| Jul 21, 3:14 PM CDT | Mesoscale Discussion | SPC | Blount, Calhoun, Cherokee, Clay, Cleburne, Colbert and 23 more | 2 hr |
Nearby
Severe Thunderstorm Watches in Alabama, 2003Severe Thunderstorm Watches in Georgia, 2003Every severe thunderstorm watch in 2003
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.