Alert archive / Alabama / Tornado Watches in 2009
Tornado Watch 786
The Storm Prediction Center issued this tornado watch at Oct 30, 2009, 5:20 PM CDT for 35 counties in Alabama; Greene County, Perry County, Wayne County, Mississippi. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Oct 30, 2009, 5:20 PM CDT (22:20 UTC)
- Expired
- Oct 30, 2009, 8:27 PM CDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 0.5 in
- Strongest gust expected
- 50 kt
All 38 counties
Autauga County, AL, Bibb County, AL, Blount County, AL, Butler County, AL, Calhoun County, AL, Chilton County, AL, Choctaw County, AL, Clarke County, AL, Clay County, AL, Conecuh County, AL, Coosa County, AL, Dallas County, AL, Elmore County, AL, Etowah County, AL, Fayette County, AL, Greene County, AL, Hale County, AL, Jefferson County, AL, Lamar County, AL, Lowndes County, AL, Marengo County, AL, Marion County, AL, Monroe County, AL, Montgomery County, AL, Perry County, AL, Pickens County, AL, Shelby County, AL, St. Clair County, AL, Sumter County, AL, Talladega County, AL, Tuscaloosa County, AL, Walker County, AL, Washington County, AL, Wilcox County, AL, Winston County, AL, Greene County, MS, Perry County, MS, Wayne County, MS
The radar
The Birmingham radar (KBMX), 45 km from the middle of the area, began a volume at 22:20 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
- 30%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 10%
- One or more gusts of 65 knots or more
- 5%
- Ten or more severe hail reports
- 5%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 40%
Warnings issued inside it
5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 30, 5:34 PM CDT | Tornado Warning | BMX | Marion, Walker, Winston | 41 min |
| Oct 30, 5:37 PM CDT | Tornado Warning | BMX | Fayette, Marion, Walker | 23 min |
| Oct 30, 5:55 PM CDT | Tornado Warning | BMX | Fayette, Walker, Winston | 50 min |
| Oct 30, 6:07 PM CDT | Tornado Warning | BMX | Winston | 19 min |
| Oct 30, 6:52 PM CDT | Severe Thunderstorm Warning | BMX | Winston | 23 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, 10.3 hours before the alert went out and 44 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
- 86 J/kg
- Mixed-layer CIN
- -31 J/kg
- Mixed-layer LCL
- 498 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 258 m²/s²
- 0-3 km storm-relative helicity
- 269 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 |
|---|---|---|---|---|
| Oct 30, 10:22 AM CDT | Mesoscale Discussion | SPC | Pickens | 83 min |
| Oct 30, 12:22 PM CDT | Tornado Watch | SPC | Choctaw, Clarke, Colbert, Cullman, Fayette, Franklin and 15 more | 8 hr |
| Oct 30, 2:11 PM CDT | Mesoscale Discussion | SPC | Choctaw, Clarke, Colbert, Fayette, Franklin, Greene and 14 more | 94 min |
| Oct 30, 4:57 PM CDT | Mesoscale Discussion | SPC | Choctaw, Clarke, Colbert, Fayette, Franklin, Greene and 12 more | 93 min |
| Oct 30, 2:03 AM CDT | Mesoscale Discussion | SPC | Adams, Benton, Bolivar, Carroll, Claiborne, Coahoma and 21 more | 57 min |
Nearby
Tornado Watches in Alabama, 2009Tornado Watches in Mississippi, 2009Every tornado watch in 2009
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.