Alert archive / Louisiana / Tornado Watches in 2006

Tornado Watch 889

December 29, 200629 parishes in Louisiana

The Storm Prediction Center issued this tornado watch at Dec 29, 2006, 8:19 PM CST for 29 parishes in Louisiana. It was in force for 10 hr.

The area

The outline as issued.

The facts

Issued
Dec 29, 2006, 8:19 PM CST (02:19 UTC)
Expired
Dec 30, 2006, 6:00 AM CST
In force
10 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 29 counties

Acadia Parish, LA, Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Cameron Parish, LA, De Soto Parish, LA, Evangeline Parish, LA, Grant Parish, LA, Iberia Parish, LA, Jackson Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Natchitoches Parish, LA, Rapides Parish, LA, Red River Parish, LA, Sabine Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, St. Mary Parish, LA, Vermilion Parish, LA, Vernon Parish, LA, Webster Parish, LA, Winn Parish, LA

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
30%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Dec 30, 12:03 AM CSTFlash Flood WarningSHVSabine4 hr
Dec 30, 1:44 AM CSTTornado WarningSHVNatchitoches, Red River28 min
Dec 30, 5:15 AM CSTTornado WarningLCHAllen15 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

Lake Charles Mun, LA (KLCH), launched 00:00Z, 2.3 hours before the alert went out and 140 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, Lake Charles Mun, LA at 00:00Z on 2006-12-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1234 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, Lake Charles Mun, LA at 00:00Z on 2006-12-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 312 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
1234 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
528 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
312 m²/s²
0-3 km storm-relative helicity
410 m²/s²
Significant tornado parameter
2.5
Supercell composite
17.2

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 29, 7:52 PM CSTMesoscale DiscussionSPCAcadia, Allen, Avoyelles, Beauregard, Bienville, Calcasieu and 18 more53 min
Dec 29, 11:41 PM CSTMesoscale DiscussionSPCAcadia, Allen, Avoyelles, Beauregard, Bienville, Bossier and 24 more94 min
Dec 30, 3:14 AM CSTMesoscale DiscussionSPCAcadia, Allen, Assumption, Avoyelles, Beauregard, Bienville and 30 more91 min
Dec 30, 5:43 AM CSTTornado WatchSPCAcadia, Allen, Ascension, Assumption, Avoyelles, Cameron and 19 more6 hr
Dec 30, 7:49 AM CSTMesoscale DiscussionSPCJefferson, Orleans, Plaquemines, Saint Bernard, Saint Charles, Saint John the Baptist and 3 more86 min
Dec 30, 8:43 AM CSTTornado WatchSPCJefferson, Lafourche, Orleans, Plaquemines, Saint Bernard, Saint Charles and 5 more5 hr
Dec 30, 10:22 AM CSTMesoscale DiscussionSPCAscension, Assumption, Jefferson, Lafourche, Livingston, Orleans and 9 more83 min
Dec 30, 1:13 PM CSTMesoscale DiscussionSPCJefferson, Lafourche, Orleans, Saint Bernard, Saint Charles, Saint Tammany62 min
Dec 30, 1:30 PM CSTTornado WatchSPCJefferson, Lafourche, Livingston, Orleans, Plaquemines, Saint Bernard and 6 more7 hr
Dec 30, 5:45 PM CSTMesoscale DiscussionSPCJefferson, Lafourche, Orleans, Plaquemines, Saint Bernard, Saint Charles and 4 more60 min
Dec 29, 7:02 PM CSTMesoscale DiscussionSPCClay, Collin, Cooke, Dallas, Delta, Denton and 8 more58 min
Dec 29, 7:27 PM CSTMesoscale DiscussionSPCHansford5 hr
Dec 30, 12:26 AM CSTMesoscale DiscussionSPCCarson, Dallam, Deaf Smith, Hansford, Hartley, Hutchinson and 6 more5 hr
Dec 30, 1:23 AM CSTMesoscale DiscussionSPCJasper, Jefferson, Newton, Orange67 min
Dec 30, 6:46 AM CSTMesoscale DiscussionSPCDallam, Deaf Smith, Hansford, Hartley, Moore, Oldham and 3 more5 hr

Nearby

Tornado Watches in Louisiana, 2006Every tornado watch in 2006

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.