Alert archive / Alabama / Tornado Watches in 2011

Tornado Watch 2

January 1, 201140 counties in Alabama; 17 parishes in Louisiana; 28 counties in Mississippi

The Storm Prediction Center issued this tornado watch at Jan 1, 2011, 3:10 AM CST for 40 counties in Alabama; 17 parishes in Louisiana; 28 counties in Mississippi. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Jan 1, 2011, 3:10 AM CST (09:10 UTC)
Expired
Jan 1, 2011, 10:00 AM CST
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
0.5 in
Strongest gust expected
60 kt
All 85 counties

Autauga County, AL, Baldwin County, AL, Bibb County, AL, Blount County, AL, Butler County, AL, Calhoun County, AL, Chilton County, AL, Choctaw County, AL, Clarke County, AL, Conecuh County, AL, Coosa County, AL, Covington County, AL, Crenshaw County, AL, Cullman County, AL, Dallas County, AL, Elmore County, AL, Escambia 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, Mobile 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, Ascension Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberville Parish, LA, Jefferson Parish, LA, Livingston Parish, LA, Orleans Parish, LA, Pointe Coupee Parish, LA, Saint Bernard Parish, LA, Saint Charles Parish, LA, Saint Helena Parish, LA, Saint John the Baptist Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Amite County, MS, Clarke County, MS, Covington County, MS, Forrest County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Kemper County, MS, Lamar County, MS, Lauderdale County, MS, Lawrence County, MS, Lincoln County, MS, Marion County, MS, Newton County, MS, Noxubee County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Smith County, MS, Stone County, MS, Walthall County, MS, Wayne County, MS, Wilkinson County, MS

The radar

The Birmingham radar (KBMX), 132 km from the middle of the area, began a volume at 09:10 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
10%
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
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jan 1, 3:10 AM CSTTornado WarningBMXPickens, Tuscaloosa35 min
Jan 1, 3:24 AM CSTTornado WarningJANNoxubee34 min
Jan 1, 3:37 AM CSTFlash Flood WarningBMXFayette, Pickens, Tuscaloosa, Walker, Winston3 hr
Jan 1, 3:37 AM CSTSevere Thunderstorm WarningBMXGreene, Pickens, Sumter38 min
Jan 1, 3:41 AM CSTSevere Thunderstorm WarningJANKemper, Lauderdale79 min
Jan 1, 3:45 AM CSTFlash Flood WarningHUNCullman, Jackson, Marshall3 hr
Jan 1, 4:13 AM CSTSevere Thunderstorm WarningBMXFayette, Greene, Pickens, Sumter, Tuscaloosa47 min
Jan 1, 4:21 AM CSTSevere Thunderstorm WarningJANCovington, Jasper, Jefferson Davis, Jones, Smith50 min
Jan 1, 4:34 AM CSTTornado WarningJANCovington, Jasper, Jones, Smith34 min
Jan 1, 4:36 AM CSTSevere Thunderstorm WarningBMXBibb, Blount, Greene, Hale, Jefferson, Marengo and 3 more39 min
Jan 1, 4:47 AM CSTFlash Flood WarningJANClarke, Jasper, Jones3 hr
Jan 1, 4:50 AM CSTTornado WarningLIXEast Feliciana, Saint Helena70 min
Jan 1, 5:19 AM CSTTornado WarningLIXPike, Walthall63 days
Jan 1, 5:27 AM CSTSevere Thunderstorm WarningBMXBibb, Greene, Hale, Perry, Sumter, Tuscaloosa48 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, 9.2 hours before the alert went out and 132 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 2011-01-01Temperature 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 2011-01-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 270 square meters per square second.19395878Sfc1 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
1020 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
270 m²/s²
0-3 km storm-relative helicity
398 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

252 
WWUS20 KWNS 010916
SEL2
SPC WW 010916
ALZ000-LAZ000-MSZ000-CWZ000-011600-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 2
NWS STORM PREDICTION CENTER NORMAN OK
310 AM CST SAT JAN 1 2011

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

       WESTERN AND NORTHERN ALABAMA
       SOUTHEASTERN LOUISIANA
       SOUTHERN AND EASTERN MISSISSIPPI
       COASTAL WATERS

EFFECTIVE THIS SATURDAY MORNING FROM 310 AM UNTIL 1000 AM CST.

TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE
MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH OF GADSDEN
ALABAMA TO 5 MILES WEST SOUTHWEST OF NEW ORLEANS LOUISIANA.  FOR
A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU2).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

OTHER WATCH INFORMATION...CONTINUE...WW 1...

DISCUSSION...BROKEN BAND OF TSTMS EXPECTED TO PERSIST ALONG
SLOWLY-MOVING COLD FRONT OVER THE LWR MS VLY.  ADDITIONAL STORMS MAY
FORM LATER THIS MORNING ALONG PRE-FRONTAL CONFLUENCE AXIS IN SE
LA/SRN MS/WRN AL.
WHILE HEIGHT FALLS OVER WW WILL BE MINIMAL...UPR DIVERGENCE WILL
EXIST IN RIGHT ENTRANCE REGION OF STRONG UPR JET.  COUPLED WITH VERY
MOIST ENVIRONMENT AND PRESENCE OF AMPLE LOW LVL SHEAR/LOW LVL
CONFLUENCE...SETUP MAY CONTINUE TO POSE A RISK FOR ISOLD TORNADOES
IN SRN TWO THIRDS OF WATCH.  FARTHER N...STRONGER DEEP SHEAR AND THE
NEWD MOVEMENT OF EXISTING ROTATING STORMS MAY POSE A THREAT FOR
ISOLD TORNADOES AS FAR NE AS NE AL...DESPITE MORE LIMITED SFC-BASED
INSTABILITY.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
450. MEAN STORM MOTION VECTOR 22040.


...CORFIDI

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 31, 10:46 PM CSTTornado WatchSPCFayette, Greene, Lamar, Marion, Pickens, Sumter and 3 more5 hr
Jan 1, 1:14 AM CSTMesoscale DiscussionSPCCullman, DeKalb, Jackson, Lawrence, Limestone, Madison and 2 more61 min
Jan 1, 6:06 AM CSTMesoscale DiscussionSPCBibb, Calhoun, Cherokee, Chilton, Choctaw, Clarke and 13 more114 min
Jan 1, 9:04 AM CSTMesoscale DiscussionSPCBaldwin, Butler, Clarke, Coffee, Conecuh, Covington and 9 more56 min
Jan 1, 9:51 AM CSTTornado WatchSPCBaldwin, Barbour, Bullock, Butler, Coffee, Conecuh and 10 more4 hr
Jan 1, 12:32 PM CSTMesoscale DiscussionSPCBaldwin, Bullock, Butler, Coffee, Conecuh, Covington and 7 more88 min

Nearby

Tornado Watches in Alabama, 2011Tornado Watches in Mississippi, 2011Tornado Watches in Louisiana, 2011Every tornado watch in 2011

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.