Alert archive / Alabama / Tornado Watches in 2010

Tornado Watch 756

November 29, 201029 counties in Alabama

The Storm Prediction Center issued this tornado watch at Nov 29, 2010, 11:41 PM CST for 29 counties in Alabama. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Nov 29, 2010, 11:41 PM CST (05:41 UTC)
Expired
Nov 30, 2010, 3:50 AM CST
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
60 kt
All 29 counties

Bibb County, AL, Blount County, AL, Colbert County, AL, Cullman County, AL, DeKalb County, AL, Etowah County, AL, Fayette County, AL, Franklin County, AL, Greene County, AL, Hale County, AL, Jackson County, AL, Jefferson County, AL, Lamar County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Marengo County, AL, Marion County, AL, Marshall County, AL, Morgan County, AL, Perry County, AL, Pickens County, AL, Shelby County, AL, St. Clair County, AL, Sumter County, AL, Tuscaloosa County, AL, Walker County, AL, Winston County, AL

The radar

The Columbus AFB radar (KGWX), 81 km from the middle of the area, began a volume at 05:41 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
40%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
20%
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
60%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Nov 29, 11:44 PM CSTTornado WarningBMXLamar, Pickens26 min
Nov 30, 12:06 AM CSTSevere Thunderstorm WarningBMXFayette, Lamar, Marion39 min
Nov 30, 12:43 AM CSTSevere Thunderstorm WarningBMXFayette, Lamar, Marion, Walker, Winston47 min
Nov 30, 12:43 AM CSTSevere Thunderstorm WarningHUNColbert, Franklin, Lawrence47 min
Nov 30, 12:56 AM CSTFlash Flood WarningBMXLamar3 hr
Nov 30, 12:59 AM CSTSevere Thunderstorm WarningHUNColbert, Lauderdale25 min
Nov 30, 1:20 AM CSTSevere Thunderstorm WarningHUNLauderdale, Lawrence, Limestone28 min
Nov 30, 1:24 AM CSTTornado WarningBMXLamar, Pickens36 min
Nov 30, 1:46 AM CSTSevere Thunderstorm WarningHUNLawrence, Limestone, Madison44 min
Nov 30, 2:28 AM CSTTornado WarningBMXPickens32 min
Nov 30, 2:33 AM CSTTornado WarningBMXPickens42 min
Nov 30, 2:37 AM CSTSevere Thunderstorm WarningHUNLimestone, Madison, Morgan38 min
Nov 30, 2:53 AM CSTTornado WarningBMXFayette, Pickens, Tuscaloosa52 min
Nov 30, 3:06 AM CSTTornado WarningBMXFayette, Pickens, Tuscaloosa39 min
Nov 30, 3:19 AM CSTFlash Flood WarningHUNMadison5 hr
Nov 30, 3:29 AM CSTTornado WarningBMXWalker, Winston46 min
Nov 30, 3:38 AM CSTTornado WarningBMXFayette, Tuscaloosa, Walker52 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, 5.7 hours before the alert went out and 105 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 2010-11-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2010-11-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 540 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
517 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
540 m²/s²
0-3 km storm-relative helicity
634 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 29, 10:57 PM CSTMesoscale DiscussionSPCBlount, Cullman, DeKalb, Fayette, Franklin, Jackson and 11 more93 min
Nov 30, 1:44 AM CSTMesoscale DiscussionSPCCullman, Fayette, Greene, Hale, Pickens, Sumter and 3 more91 min
Nov 30, 3:17 AM CSTMesoscale DiscussionSPCAutauga, Bibb, Blount, Butler, Calhoun, Chambers and 36 more58 min
Nov 30, 3:39 AM CSTMesoscale DiscussionSPCBlount, Cullman, Jefferson, Tuscaloosa, Walker96 min
Nov 30, 3:49 AM CSTTornado WatchSPCAutauga, Bibb, Blount, Calhoun, Cherokee, Chilton and 34 more8 hr
Nov 30, 6:30 AM CSTMesoscale DiscussionSPCBibb, Blount, Calhoun, Chilton, Choctaw, Clarke and 14 more90 min
Nov 30, 7:00 AM CSTMesoscale DiscussionSPCBaldwin, Barbour, Bullock, Butler, Chambers, Coffee and 18 more60 min
Nov 30, 7:43 AM CSTTornado WatchSPCBaldwin, Barbour, Bullock, Butler, Chambers, Coffee and 14 more8 hr
Nov 30, 9:38 AM CSTMesoscale DiscussionSPCAutauga, Bullock, Butler, Calhoun, Chambers, Cherokee and 20 more97 min
Nov 29, 8:24 PM CSTMesoscale DiscussionSPCAmite, Attala, Chickasaw, Choctaw, Clay, Copiah and 20 more96 min
Nov 29, 8:49 PM CSTTornado WatchSPCAdams, Amite, Attala, Calhoun, Carroll, Chickasaw and 46 more7 hr

Nearby

Tornado Watches in Alabama, 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.