Alert archive / Mississippi / Tornado Watches in 2011

Tornado Watch 140

April 15, 201126 counties in Alabama; 14 parishes in Louisiana; 51 counties in Mississippi

The Storm Prediction Center issued this tornado watch at Apr 15, 2011, 7:32 AM CDT for 26 counties in Alabama; 14 parishes in Louisiana; 51 counties in Mississippi. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Apr 15, 2011, 7:32 AM CDT (12:32 UTC)
Expired
Apr 15, 2011, 3:00 PM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 91 counties

Blount County, AL, Choctaw County, AL, Clarke County, AL, Colbert County, AL, Cullman County, AL, Fayette County, AL, Franklin County, AL, Greene County, AL, Hale 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, Mobile County, AL, Morgan County, AL, Pickens County, AL, Sumter County, AL, Tuscaloosa County, AL, Walker County, AL, Washington County, AL, Winston County, AL, Avoyelles Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Grant Parish, LA, LaSalle Parish, LA, Madison Parish, LA, Rapides Parish, LA, Richland Parish, LA, Tensas Parish, LA, Vernon Parish, LA, Winn Parish, LA, Adams County, MS, Amite County, MS, Attala County, MS, Carroll County, MS, Choctaw County, MS, Claiborne County, MS, Clarke County, MS, Clay County, MS, Copiah County, MS, Covington County, MS, Forrest County, MS, Franklin County, MS, George County, MS, Greene County, MS, Grenada County, MS, Hinds County, MS, Holmes County, MS, Issaquena County, MS, Jasper County, MS, Jefferson County, MS, Jefferson Davis County, MS, Jones County, MS, Kemper County, MS, Lamar County, MS, Lauderdale County, MS, Lawrence County, MS, Leake County, MS, Lincoln County, MS, Lowndes County, MS, Madison County, MS, Marion County, MS, Montgomery County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Perry County, MS, Pike County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Smith County, MS, Stone County, MS, Walthall County, MS, Warren County, MS, Wayne County, MS, Webster County, MS, Wilkinson County, MS, Winston County, MS, Yazoo County, MS

The radar

The Columbus AFB radar (KGWX), 101 km from the middle of the area, began a volume at 12:31 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
80%
One or more EF2 to EF5 tornadoes
50%
Ten or more severe wind reports
95%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
95%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 15, 7:42 AM CDTSevere Thunderstorm WarningJANEast Carroll, Madison, West Carroll63 min
Apr 15, 7:50 AM CDTSevere Thunderstorm WarningJANAttala, Choctaw, Winston40 min
Apr 15, 8:00 AM CDTFlash Flood WarningJANHolmes, Humphreys, Sharkey, Yazoo5 hr
Apr 15, 8:06 AM CDTSevere Thunderstorm WarningJANCatahoula, Franklin54 min
Apr 15, 8:09 AM CDTTornado WarningJANAttala, Carroll, Holmes, Yazoo66 min
Apr 15, 8:15 AM CDTSevere Thunderstorm WarningJANChoctaw, Clay, Lowndes, Montgomery, Oktibbeha, Webster60 min
Apr 15, 8:18 AM CDTSevere Thunderstorm WarningJANHolmes, Yazoo27 min
Apr 15, 8:23 AM CDTSevere Thunderstorm WarningLCHRapides, Vernon67 min
Apr 15, 8:27 AM CDTTornado WarningJANCatahoula, Franklin16 min
Apr 15, 8:33 AM CDTSevere Thunderstorm WarningJANAttala, Carroll, Choctaw57 min
Apr 15, 8:36 AM CDTTornado WarningJANAttala, Holmes54 min
Apr 15, 8:50 AM CDTTornado WarningJANAttala, Carroll, Holmes40 min
Apr 15, 8:54 AM CDTFlash Flood WarningJANAttala, Carroll, Choctaw, Clay, Montgomery, Oktibbeha and 1 more3 hr
Apr 15, 9:08 AM CDTSevere Thunderstorm WarningJANFranklin, Madison, Tensas67 min
Apr 15, 9:11 AM CDTSevere Thunderstorm WarningLCHAvoyelles, Rapides42 min
Apr 15, 9:18 AM CDTSevere Thunderstorm WarningJANChoctaw, Lowndes, Noxubee, Oktibbeha, Winston42 min
Apr 15, 9:24 AM CDTSevere Thunderstorm WarningJANHolmes, Humphreys, Yazoo66 min
Apr 15, 9:32 AM CDTSevere Thunderstorm WarningJANCatahoula, Concordia58 min
Apr 15, 9:34 AM CDTSevere Thunderstorm WarningJANClaiborne, Hinds, Warren56 min
Apr 15, 9:45 AM CDTTornado WarningJANAttala, Holmes60 min
Apr 15, 10:01 AM CDTFlash Flood WarningJANChoctaw, Clay, Lowndes, Noxubee, Oktibbeha, Winston5 hr
Apr 15, 10:03 AM CDTTornado WarningJANHolmes, Humphreys, Yazoo57 min
Apr 15, 10:11 AM CDTFlash Flood WarningBMXLamar6 hr
Apr 15, 10:12 AM CDTSevere Thunderstorm WarningJANHinds, Madison63 min
Apr 15, 10:15 AM CDTTornado WarningMOBWayne45 min
Apr 15, 10:20 AM CDTTornado WarningMOBWashington40 min
Apr 15, 10:21 AM CDTSevere Thunderstorm WarningJANAdams, Franklin, Jefferson15 min
Apr 15, 10:26 AM CDTTornado Warning EmergencyJANClaiborne, Hinds, Madison64 min
Apr 15, 10:28 AM CDTSevere Thunderstorm WarningJANClarke47 min
Apr 15, 10:33 AM CDTTornado WarningJANClarke57 min
Apr 15, 10:34 AM CDTTornado WarningMOBGreene, Perry41 min
Apr 15, 10:41 AM CDTTornado WarningJANAttala, Choctaw, Montgomery64 min
Apr 15, 10:42 AM CDTFlash Flood WarningJANHinds, Madison, Rankin2 hr
Apr 15, 10:50 AM CDTTornado WarningMOBClarke, Washington40 min
Apr 15, 10:50 AM CDTTornado WarningJANCarroll, Choctaw, Montgomery31 min
Apr 15, 10:56 AM CDTTornado WarningMOBChoctaw49 min
Apr 15, 10:59 AM CDTSevere Thunderstorm WarningBMXBlount, Jefferson, St. Clair46 min
Apr 15, 11:09 AM CDTTornado WarningMOBWashington51 min
Apr 15, 11:14 AM CDTTornado WarningJANClarke18 min
Apr 15, 11:18 AM CDTTornado WarningJANNoxubee, Oktibbeha, Winston41 min
Apr 15, 11:20 AM CDTTornado Warning EmergencyJANMadison, Rankin39 min
Apr 15, 11:26 AM CDTTornado WarningMOBClarke, Monroe49 min
Apr 15, 11:28 AM CDTSevere Thunderstorm WarningJANAttala, Choctaw47 min
Apr 15, 11:35 AM CDTTornado WarningMOBWayne40 min
Apr 15, 11:39 AM CDTSevere Thunderstorm WarningHUNCullman21 min
Apr 15, 11:41 AM CDTTornado WarningMOBChoctaw64 min
Apr 15, 11:42 AM CDTTornado WarningJANClay, Lowndes47 min
Apr 15, 11:43 AM CDTSevere Thunderstorm WarningHUNMarshall17 min
Apr 15, 11:46 AM CDTTornado WarningJANAttala, Choctaw33 min
Apr 15, 11:49 AM CDTTornado WarningJANLeake, Scott43 min
Apr 15, 11:52 AM CDTTornado WarningBMXMarengo38 min
Apr 15, 11:52 AM CDTTornado WarningMOBChoctaw, Clarke, Washington38 min
Apr 15, 11:55 AM CDTFlash Flood WarningJANAttala, Carroll, Choctaw, Clay, Holmes, Lowndes and 4 more3 hr
Apr 15, 12:09 PM CDTTornado WarningJANOktibbeha51 min
Apr 15, 12:14 PM CDTTornado WarningJANLeake, Neshoba61 min
Apr 15, 12:15 PM CDTSevere Thunderstorm WarningBMXLamar, Pickens34 min
Apr 15, 12:20 PM CDTTornado WarningMOBChoctaw, Clarke, Washington40 min
Apr 15, 12:22 PM CDTFlash Flood WarningHUNColbert, Lauderdale, Lawrence, Limestone3 hr
Apr 15, 12:24 PM CDTTornado WarningBMXMarengo51 min
Apr 15, 12:26 PM CDTSevere Thunderstorm WarningHUNCullman, Marshall23 min
Apr 15, 12:27 PM CDTTornado WarningJANClaiborne, Copiah, Hinds, Rankin, Simpson63 min
Apr 15, 12:36 PM CDTSevere Thunderstorm WarningBMXBlount, Jefferson, St. Clair27 min
Apr 15, 12:44 PM CDTTornado WarningMOBWashington46 min
Apr 15, 12:49 PM CDTTornado WarningJANKemper56 min
Apr 15, 12:51 PM CDTTornado WarningMOBClarke, Wilcox33 min
Apr 15, 12:56 PM CDTTornado WarningJANClay, Lowndes, Oktibbeha43 min
Apr 15, 12:59 PM CDTTornado WarningBMXDallas, Marengo, Perry46 min
Apr 15, 1:06 PM CDTTornado WarningJANCopiah, Lincoln54 min
Apr 15, 1:09 PM CDTTornado WarningMOBWashington51 min
Apr 15, 1:10 PM CDTFlash Flood WarningBMXFayette, Lamar, Marion, Walker, Winston3 hr
Apr 15, 1:12 PM CDTTornado WarningJANRankin, Simpson48 min
Apr 15, 1:14 PM CDTFlash Flood WarningHUNCullman6 hr
Apr 15, 1:22 PM CDTTornado WarningMOBClarke, Washington21 min
Apr 15, 1:25 PM CDTTornado Warning EmergencyBMXGreene, Sumter65 min
Apr 15, 1:26 PM CDTSevere Thunderstorm WarningJANConcordia64 min
Apr 15, 1:42 PM CDTTornado WarningJANScott, Smith48 min
Apr 15, 1:46 PM CDTTornado WarningMOBClarke, Washington44 min
Apr 15, 1:46 PM CDTTornado WarningJANKemper, Neshoba59 min
Apr 15, 1:46 PM CDTTornado WarningJANCopiah, Simpson59 min
Apr 15, 1:48 PM CDTTornado WarningJANAttala, Holmes57 min
Apr 15, 1:49 PM CDTSevere Thunderstorm WarningHUNLauderdale26 min
Apr 15, 2:06 PM CDTSevere Thunderstorm WarningMOBChoctaw27 min
Apr 15, 2:06 PM CDTSevere Thunderstorm WarningMOBGeorge, Greene39 min
Apr 15, 2:12 PM CDTTornado WarningJANJasper, Newton63 min
Apr 15, 2:17 PM CDTSevere Thunderstorm WarningJANConcordia58 min
Apr 15, 2:22 PM CDTTornado WarningMOBClarke, Monroe, Wilcox38 min
Apr 15, 2:23 PM CDTTornado WarningJANJasper, Smith67 min
Apr 15, 2:24 PM CDTTornado Warning EmergencyBMXGreene, Hale, Tuscaloosa51 min
Apr 15, 2:25 PM CDTSevere Thunderstorm WarningLCHAvoyelles, Saint Landry50 min
Apr 15, 2:31 PM CDTTornado WarningBMXMarengo, Sumter29 min
Apr 15, 2:35 PM CDTTornado WarningLCHAvoyelles, Saint Landry25 min
Apr 15, 2:39 PM CDTFlash Flood WarningBMXGreene, Pickens, Sumter3 hr
Apr 15, 2:41 PM CDTTornado WarningBMXGreene, Tuscaloosa64 min
Apr 15, 2:41 PM CDTTornado Warning EmergencyJANAttala, Choctaw49 min
Apr 15, 2:42 PM CDTTornado WarningJANKemper18 min
Apr 15, 2:48 PM CDTTornado WarningJANLauderdale57 min
Apr 15, 2:49 PM CDTTornado WarningBMXGreene, Hale, Sumter41 min
Apr 15, 2:56 PM CDTTornado WarningBMXGreene, Hale, Marengo, Perry, Sumter49 min
Apr 15, 2:56 PM CDTSevere Thunderstorm WarningLIXAmite, Wilkinson64 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

Jackson, MS (KJAN), launched 12:00Z, 0.5 hours before the alert went out and 143 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, Jackson, MS at 12:00Z on 2011-04-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1458 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Jackson, MS at 12:00Z on 2011-04-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 382 square meters per square second.1939587897Sfc1 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
1458 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
523 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
382 m²/s²
0-3 km storm-relative helicity
565 m²/s²
Significant tornado parameter
4.0
Supercell composite
14.6

Open this sounding in Storm Lab

The text

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

493 
WWUS20 KWNS 151242
SEL0
SPC WW 151242
ALZ000-LAZ000-MSZ000-152000-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 140
NWS STORM PREDICTION CENTER NORMAN OK
735 AM CDT FRI APR 15 2011

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

       WESTERN AND NORTHERN ALABAMA
       CENTRAL AND EASTERN LOUISIANA
       CENTRAL AND SOUTHERN MISSISSIPPI

EFFECTIVE THIS FRIDAY MORNING AND AFTERNOON FROM 735 AM UNTIL 300
PM CDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 95 STATUTE
MILES EAST AND WEST OF A LINE FROM 25 MILES NORTHEAST OF MUSCLE
SHOALS ALABAMA TO 45 MILES SOUTH OF NATCHEZ MISSISSIPPI.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU0).

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 139...

DISCUSSION...NE-SW MS/LA SQLN EXPECTED TO CONTINUE GENERALLY EWD
THROUGH EARLY AFTERNOON.  SYSTEM MAY BREAK INTO MORE SEMI-DISCRETE
STORMS/LINE SEGMENTS...AND ADDITIONAL STORMS MAY FORM IN
CONFLUENT/MOISTENING LOW-LVL FLOW AHEAD OF LINE...AS SFC HEATING
FURTHER DESTABILIZES REGION.  12Z KJAN SOUNDING AND UPSTREAM WIND
PROFILES SUGGEST WW AREA WILL HAVE THERMODYNAMIC AND WIND
ENVIRONMENT SUPPORTIVE OF SUSTAINED SUPERCELLS AND LEWPS.  THESE MAY
YIELD A COUPLE STRONG TORNADOES...IN ADDITION TO DMGG WIND AND HAIL.
STORMS IN NRN AL MAY REMAIN SLIGHTLY ELEVATED...BUT WILL STILL HAVE
THE POTENTIAL TO PRODUCE LOCALLY DMGG WIND AND PERHAPS ISOLD
TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
550. MEAN STORM MOTION VECTOR 25040.


...CORFIDI

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 15, 4:21 AM CDTMesoscale DiscussionSPCColbert, Franklin, Lamar, Lauderdale, Marion, Pickens84 min
Apr 15, 10:28 AM CDTMesoscale DiscussionSPCAutauga, Baldwin, Bibb, Blount, Butler, Chilton and 34 more2 hr
Apr 15, 11:21 AM CDTTornado WatchSPCAutauga, Baldwin, Barbour, Bibb, Blount, Bullock and 44 more9 hr
Apr 15, 1:30 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Blount, Bullock, Butler, Calhoun and 46 more2 hr
Apr 15, 3:35 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Blount, Bullock, Butler, Chambers and 39 more85 min
Apr 15, 5:57 PM CDTMesoscale DiscussionSPCColbert, Franklin, Lamar, Lauderdale, Lawrence, Marion2 hr
Apr 14, 11:24 PM CDTSevere Thunderstorm WatchSPCBossier, Caddo, Claiborne, De Soto, Webster3 hr
Apr 14, 11:56 PM CDTMesoscale DiscussionSPCBossier, Caddo, De Soto, Webster94 min
Apr 15, 1:27 AM CDTMesoscale DiscussionSPCBienville, Bossier, Claiborne, East Carroll, Jackson, Lincoln and 5 more93 min
Apr 15, 2:19 AM CDTTornado WatchSPCBienville, Bossier, Caddo, Caldwell, Catahoula, Claiborne and 20 more8 hr
Apr 15, 2:41 PM CDTTornado WatchSPCAcadia, Ascension, Assumption, Avoyelles, Concordia, East Baton Rouge and 19 more7 hr
Apr 15, 6:09 PM CDTMesoscale DiscussionSPCAscension, Assumption, East Baton Rouge, East Feliciana, Iberia, Iberville and 12 more96 min
Apr 15, 12:29 PM CDTMesoscale DiscussionSPCAlcorn, Benton, DeSoto, Lafayette, Marshall, Panola and 4 more61 min
Apr 15, 2:09 PM CDTTornado WatchSPCAlcorn, Benton, Calhoun, Chickasaw, DeSoto, Itawamba and 13 more7 hr

Nearby

Tornado Watches in Mississippi, 2011Tornado Watches in Alabama, 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.