Alert archive / Alabama / Severe Thunderstorm Watches in 2020
Severe Thunderstorm Watch 362
The Storm Prediction Center issued this severe thunderstorm watch at Jul 12, 2020, 12:09 PM CDT for 35 counties in Alabama; 5 counties in Mississippi. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 12, 2020, 12:09 PM CDT (17:09 UTC)
- Expired
- Jul 12, 2020, 6:29 PM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 60 kt
All 40 counties
Autauga County, AL, Barbour County, AL, Bibb County, AL, Blount County, AL, Bullock County, AL, Calhoun County, AL, Chambers County, AL, Chilton County, AL, Clay County, AL, Cleburne County, AL, Coosa County, AL, Dallas County, AL, Elmore 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, Montgomery County, AL, Perry County, AL, Pickens County, AL, Pike County, AL, Randolph 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, Clay County, MS, Kemper County, MS, Lowndes County, MS, Noxubee County, MS, Oktibbeha County, MS
The radar
The Birmingham radar (KBMX), 6 km from the middle of the area, began a volume at 17:09 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
- 2%
- Ten or more severe wind reports
- 70%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 20%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
12 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 12, 12:09 PM CDT | Severe Thunderstorm Warning | BMX | Walker | 66 min |
| Jul 12, 12:25 PM CDT | Severe Thunderstorm Warning | BMX | Etowah, St. Clair | 65 min |
| Jul 12, 12:29 PM CDT | Severe Thunderstorm Warning | BMX | Fayette, Lamar | 61 min |
| Jul 12, 12:42 PM CDT | Severe Thunderstorm Warning | JAN | Clay, Lowndes | 63 min |
| Jul 12, 12:49 PM CDT | Severe Thunderstorm Warning | BMX | Jefferson, Walker | 56 min |
| Jul 12, 1:06 PM CDT | Severe Thunderstorm Warning | BMX | Calhoun, Talladega | 54 min |
| Jul 12, 1:25 PM CDT | Severe Thunderstorm Warning | BMX | Shelby | 65 min |
| Jul 12, 2:00 PM CDT | Severe Thunderstorm Warning | BMX | St. Clair, Talladega | 46 min |
| Jul 12, 2:23 PM CDT | Severe Thunderstorm Warning | BMX | Bibb, Chilton, Perry | 55 min |
| Jul 12, 2:25 PM CDT | Severe Thunderstorm Warning | BMX | Clay, Coosa, Talladega, Tallapoosa | 66 min |
| Jul 12, 3:17 PM CDT | Severe Thunderstorm Warning | BMX | Chambers, Elmore, Lee, Macon, Tallapoosa | 58 min |
| Jul 12, 3:49 PM CDT | Severe Thunderstorm Warning | BMX | Autauga, Bullock, Elmore, Lowndes, Macon, Montgomery and 1 more | 60 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, 5.2 hours before the alert went out and 5 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
- 43 J/kg
- Mixed-layer CIN
- -299 J/kg
- Mixed-layer LCL
- 1793 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 37 m²/s²
- 0-3 km storm-relative helicity
- 68 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 12, 10:46 AM CDT | Mesoscale Discussion | SPC | Autauga, Bibb, Blount, Chilton, Clay, Coosa and 17 more | 119 min |
| Jul 12, 1:40 PM CDT | Mesoscale Discussion | SPC | Autauga, Bibb, Chambers, Chilton, Clay, Coosa and 5 more | 95 min |
| Jul 12, 2:51 PM CDT | Mesoscale Discussion | SPC | Baldwin, Barbour, Bullock, Butler, Clarke, Coffee and 18 more | 84 min |
| Jul 12, 3:40 PM CDT | Severe Thunderstorm Watch | SPC | Baldwin, Butler, Choctaw, Clarke, Coffee, Conecuh and 11 more | 6 hr |
| Jul 12, 6:28 PM CDT | Mesoscale Discussion | SPC | Baldwin, Clarke, Coffee, Conecuh, Covington, Escambia and 3 more | 92 min |
Nearby
Severe Thunderstorm Watches in Alabama, 2020Severe Thunderstorm Watches in Mississippi, 2020Every severe thunderstorm watch in 2020
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.