Alert archive / Alabama / Severe Thunderstorm Watches in 2012
Severe Thunderstorm Watch 143
The Storm Prediction Center issued this severe thunderstorm watch at Apr 5, 2012, 9:14 AM CDT for 40 counties in Alabama. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 5, 2012, 9:14 AM CDT (14:14 UTC)
- Expired
- Apr 5, 2012, 5:00 PM CDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 40 counties
Autauga County, AL, Barbour County, AL, Bibb County, AL, Bullock County, AL, Butler County, AL, Chambers County, AL, Chilton County, AL, Choctaw County, AL, Clarke County, AL, Conecuh County, AL, Coosa County, AL, Covington County, AL, Crenshaw County, AL, Dallas County, AL, Elmore County, AL, Escambia County, AL, Fayette County, AL, Greene County, AL, Hale County, AL, Jefferson County, AL, Lamar County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Marengo County, AL, Monroe County, AL, Montgomery County, AL, Perry County, AL, Pickens County, AL, Pike County, AL, Russell County, AL, Shelby County, AL, St. Clair County, AL, Sumter County, AL, Talladega County, AL, Tallapoosa County, AL, Tuscaloosa County, AL, Walker County, AL, Washington County, AL, Wilcox County, AL
The radar
The Birmingham radar (KBMX), 78 km from the middle of the area, began a volume at 14:18 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 50%
- One or more gusts of 65 knots or more
- 40%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
9 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 5, 9:41 AM CDT | Severe Thunderstorm Warning | BMX | Greene, Pickens, Sumter | 64 min |
| Apr 5, 10:24 AM CDT | Severe Thunderstorm Warning | MOB | Choctaw | 66 min |
| Apr 5, 10:26 AM CDT | Severe Thunderstorm Warning | BMX | Greene, Hale, Tuscaloosa | 64 min |
| Apr 5, 11:07 AM CDT | Severe Thunderstorm Warning | BMX | Bibb, Perry | 53 min |
| Apr 5, 11:24 AM CDT | Severe Thunderstorm Warning | MOB | Choctaw, Clarke, Washington, Wilcox | 66 min |
| Apr 5, 11:44 AM CDT | Severe Thunderstorm Warning | BMX | Dallas, Marengo | 46 min |
| Apr 5, 1:01 PM CDT | Severe Thunderstorm Warning | MOB | Conecuh, Escambia, Monroe | 59 min |
| Apr 5, 4:17 PM CDT | Severe Thunderstorm Warning | BMX | Lamar | 28 min |
| Apr 5, 4:41 PM CDT | Severe Thunderstorm Warning | BMX | Fayette, Lamar, Marion | 49 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, 2.2 hours before the alert went out and 78 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
- 315 J/kg
- Mixed-layer CIN
- -31 J/kg
- Mixed-layer LCL
- 754 m above ground
- 0-6 km bulk shear
- 40 kt
- 0-1 km storm-relative helicity
- -91 m²/s²
- 0-3 km storm-relative helicity
- -43 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -1.5
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 5, 7:36 AM CDT | Mesoscale Discussion | SPC | Choctaw, Greene, Hale, Marengo, Perry, Pickens and 2 more | 54 min |
| Apr 5, 10:41 AM CDT | Mesoscale Discussion | SPC | Autauga, Bibb, Butler, Chilton, Choctaw, Clarke and 15 more | 94 min |
| Apr 5, 12:09 PM CDT | Mesoscale Discussion | SPC | Colbert, Cullman, Franklin, Lauderdale, Lawrence, Limestone and 4 more | 96 min |
| Apr 5, 1:12 PM CDT | Mesoscale Discussion | SPC | Barbour, Bullock, Chambers, Clay, Coffee, Covington and 11 more | 93 min |
| Apr 5, 1:21 PM CDT | Severe Thunderstorm Watch | SPC | Colbert, DeKalb, Franklin, Jackson, Lauderdale, Lawrence and 4 more | 8 hr |
| Apr 5, 1:58 PM CDT | Severe Thunderstorm Watch | SPC | Coffee, Dale, Geneva, Henry, Houston | 6 hr |
| Apr 5, 3:06 PM CDT | Mesoscale Discussion | SPC | Colbert, DeKalb, Franklin, Jackson, Lauderdale, Lawrence and 4 more | 54 min |
| Apr 5, 3:46 PM CDT | Mesoscale Discussion | SPC | Blount, Calhoun, Cullman, Etowah, Fayette, Jefferson and 7 more | 59 min |
| Apr 5, 3:49 PM CDT | Mesoscale Discussion | SPC | Geneva, Henry, Houston | 86 min |
| Apr 5, 6:14 PM CDT | Severe Thunderstorm Watch | SPC | Autauga, Bibb, Blount, Bullock, Calhoun, Chambers and 21 more | 3 hr |
| Apr 5, 6:15 PM CDT | Mesoscale Discussion | SPC | Autauga, Bibb, Blount, Bullock, Calhoun, Chambers and 23 more | 45 min |
Nearby
Severe Thunderstorm Watches in Alabama, 2012Every severe thunderstorm watch 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.