Alert archive / Alabama / Tornado Watches in 2010

Tornado Watch 99

April 24, 201033 counties in Alabama; 30 counties in Georgia; 6 counties in Mississippi

The Storm Prediction Center issued this tornado watch at Apr 24, 2010, 7:11 PM CDT for 33 counties in Alabama; 30 counties in Georgia; 6 counties in Mississippi. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Apr 24, 2010, 7:11 PM CDT (00:11 UTC)
Expired
Apr 25, 2010, 2:00 AM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 69 counties

Autauga County, AL, Bibb County, AL, Blount County, AL, Calhoun County, AL, Cherokee County, AL, Chilton County, AL, Choctaw County, AL, Clay County, AL, Cleburne County, AL, Coosa County, AL, Cullman County, AL, Dallas County, AL, DeKalb County, AL, Elmore County, AL, Etowah County, AL, Fayette County, AL, Greene County, AL, Hale County, AL, Jackson County, AL, Jefferson County, AL, Marengo County, AL, Marshall County, AL, Perry County, AL, Pickens County, AL, Randolph County, AL, Shelby County, AL, St. Clair County, AL, Sumter County, AL, Talladega County, AL, Tallapoosa County, AL, Tuscaloosa County, AL, Walker County, AL, Wilcox County, AL, Bartow County, GA, Carroll County, GA, Catoosa County, GA, Chattooga County, GA, Cherokee County, GA, Cobb County, GA, Dade County, GA, Dawson County, GA, DeKalb County, GA, Douglas County, GA, Fannin County, GA, Floyd County, GA, Forsyth County, GA, Fulton County, GA, Gilmer County, GA, Gordon County, GA, Gwinnett County, GA, Hall County, GA, Haralson County, GA, Heard County, GA, Lumpkin County, GA, Murray County, GA, Paulding County, GA, Pickens County, GA, Polk County, GA, Towns County, GA, Union County, GA, Walker County, GA, White County, GA, Whitfield County, GA, Clarke County, MS, Jasper County, MS, Kemper County, MS, Lauderdale County, MS, Newton County, MS, Noxubee County, MS

The radar

The Birmingham radar (KBMX), 81 km from the middle of the area, began a volume at 00:14 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
50%
One or more EF2 to EF5 tornadoes
40%
Ten or more severe wind reports
60%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
50%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
95%

Warnings issued inside it

38 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 24, 7:12 PM CDTTornado WarningHUNCullman, Marshall, Morgan33 min
Apr 24, 7:13 PM CDTTornado WarningBMXFayette, Lamar, Pickens47 min
Apr 24, 7:24 PM CDTSevere Thunderstorm WarningBMXFayette, Lamar36 min
Apr 24, 7:35 PM CDTTornado WarningJANKemper55 min
Apr 24, 7:41 PM CDTTornado WarningHUNMadison, Marshall34 min
Apr 24, 7:44 PM CDTTornado WarningBMXFayette, Pickens, Tuscaloosa46 min
Apr 24, 7:48 PM CDTSevere Thunderstorm WarningBMXPickens27 min
Apr 24, 7:58 PM CDTFlash Flood WarningBMXFayette, Lamar, Pickens3 hr
Apr 24, 8:09 PM CDTTornado WarningBMXFayette, Pickens, Tuscaloosa25 min
Apr 24, 8:11 PM CDTTornado WarningHUNDeKalb, Jackson, Marshall34 min
Apr 24, 8:15 PM CDTTornado WarningBMXFayette, Walker45 min
Apr 24, 8:36 PM CDTFlash Flood WarningHUNCullman4 hr
Apr 24, 8:53 PM CDTTornado WarningHUNCullman37 min
Apr 24, 9:11 PM CDTTornado WarningBMXBlount49 min
Apr 24, 9:15 PM CDTSevere Thunderstorm WarningJANKemper, Lauderdale45 min
Apr 24, 9:37 PM CDTTornado WarningBMXGreene, Sumter20 min
Apr 24, 10:01 PM CDTTornado Warning EmergencyBMXWalker29 min
Apr 24, 10:15 PM CDTTornado WarningHUNDeKalb, Marshall30 min
Apr 24, 10:22 PM CDTTornado Warning EmergencyBMXBlount, Jefferson, Walker38 min
Apr 24, 10:40 PM CDTTornado WarningHUNDeKalb35 min
Apr 24, 10:56 PM CDTTornado WarningFFCChattooga, Dade, Walker64 min
Apr 24, 11:12 PM CDTTornado WarningHUNDeKalb27 min
Apr 24, 11:21 PM CDTTornado WarningHUNDeKalb17 min
Apr 24, 11:33 PM CDTTornado WarningBMXEtowah, St. Clair42 min
Apr 24, 11:40 PM CDTSevere Thunderstorm WarningBMXBibb, Chilton, Hale, Shelby, Tuscaloosa26 min
Apr 24, 11:41 PM CDTSevere Thunderstorm WarningBMXBlount, Jefferson38 min
Apr 24, 11:42 PM CDTTornado WarningHUNDeKalb33 min
Apr 24, 11:44 PM CDTFlash Flood WarningHUNDeKalb3 hr
Apr 24, 11:48 PM CDTTornado WarningFFCWalker, Whitfield42 min
Apr 25, 12:07 AM CDTTornado WarningBMXCherokee9 min
Apr 25, 12:07 AM CDTSevere Thunderstorm WarningFFCFannin, Gilmer, Murray38 min
Apr 25, 12:09 AM CDTTornado WarningHUNDeKalb36 min
Apr 25, 12:18 AM CDTTornado WarningBMXCherokee27 min
Apr 25, 12:18 AM CDTTornado WarningFFCChattooga49 min
Apr 25, 12:40 AM CDTSevere Thunderstorm WarningBMXCherokee, Etowah33 min
Apr 25, 12:40 AM CDTFlash Flood WarningFFCWalker, Whitfield113 min
Apr 25, 12:40 AM CDTTornado WarningFFCFannin, Gilmer, Murray30 min
Apr 25, 12:49 AM CDTSevere Thunderstorm WarningFFCChattooga, Floyd41 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 00:00Z, 0.2 hours before the alert went out and 81 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.

Skew-T log-pSkew-T log-p diagram, Birmingham, AL at 00:00Z on 2010-04-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1231 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Birmingham, AL at 00:00Z on 2010-04-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 415 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1231 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
483 m above ground
0-6 km bulk shear
69 kt
0-1 km storm-relative helicity
415 m²/s²
0-3 km storm-relative helicity
438 m²/s²
Significant tornado parameter
3.6
Supercell composite
15.1

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 24, 7:19 PM CDTMesoscale DiscussionSPCBaldwin, Butler, Clarke, Coffee, Conecuh, Covington and 11 more56 min
Apr 24, 9:58 PM CDTMesoscale DiscussionSPCBaldwin, Barbour, Bullock, Butler, Chambers, Coffee and 13 more32 min
Apr 24, 10:46 PM CDTTornado WatchSPCBarbour, Bullock, Butler, Chambers, Coffee, Covington and 12 more7 hr
Apr 24, 11:27 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Blount, Calhoun, Cherokee, Chilton and 25 more63 min
Apr 25, 3:01 AM CDTMesoscale DiscussionSPCHenry, Houston89 min
Apr 24, 11:55 PM CDTMesoscale DiscussionSPCBanks, Barrow, Butts, Clarke, Columbia, Elbert and 25 more35 min
Apr 25, 12:17 AM CDTTornado WatchSPCBaldwin, Banks, Barrow, Bartow, Bibb, Bleckley and 101 more8 hr
Apr 25, 5:38 AM CDTMesoscale DiscussionSPCAppling, Atkinson, Baker, Ben Hill, Berrien, Brooks and 32 more67 min

Nearby

Tornado Watches in Alabama, 2010Tornado Watches in Georgia, 2010Tornado Watches in Mississippi, 2010Every tornado watch in 2010

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.