THE NOVEMBER 23, 2004 TORNADO OUTBREAK

Sam Shamburger &  Roger Erickson*

National Weather Service Forecast Office
Lake Charles, Louisiana

INTRODUCTION

A significant tornado outbreak affected much of the southern United States on November 23^rd and early November 24^th.  Numerous tornadoes tore through portions of central and eastern Texas, Louisiana, Mississippi, Alabama, Florida, Georgia, South Carolina, and Indiana, causing 4 deaths and numerous injuries.  In total, this tornado outbreak produced over 50 confirmed tornadoes.

The portions of the NWS Lake Charles County Warning Area that were most affected by this outbreak were eastern Texas and central Louisiana.  During the afternoon and evening of the 23rd, Several intense rotating thunderstorms called supercells caused the majority of the severe weather across our area.  The first supercell of the outbreak moved northeastward across Tyler, Jasper, and far northern Newton counties.  While this storm did not spawn any tornadoes in our region, it did cause large hail up to golf ball size, and damaging winds in excess of 60 mph.  A second supercell (tracks shown in red) developed near Baytown, Texas, and produced 7 tornadoes along its extensive 150 mile trek across the Lake Charles county warning area.  This supercell continued into northern Louisiana, and later spawned the deadly tornado in Olla, Louisiana.  A third supercell (tracks shown in blue) was responsible for 4 tornadoes across eastern Texas and central Louisiana. 

In addition to the tornadoes, an extensive squall line moved eastward out of central Texas late on November 23^rd into the 24^th.  This line of severe thunderstorms swept across the entire Lake Charles County Warning area.  By sunrise on November 24th, severe thunderstorm and tornado warnings had been issued for every county and parish in the Lake Charles county warning area.  This was the most intense severe weather outbreak across the region since Hurricane Lili produced 12 tornadoes across central and southern Louisiana on October 3rd, 2002.

Below is a map of the tornado damage tracks across the Lake Charles warning area. Click on each track to see a detailed description of the tornado and view a high resolution map of the areas impacted.

What was the cause of all these tornadoes?  By the afternoon of November 23^rd, a powerful storm system was moving out of the southwestern United States into the southern Plains.  At the surface, a very warm, moist air mass was in place across the area, with temperatures in the 70�s and 80�s and dewpoints in the upper 60�s and lower 70�s.  This warm, humid air created a very unstable atmosphere, leading to the explosive thunderstorm development.  Very strong wind speeds were found at all levels of the atmosphere, (up to 120 knots at 200 mb!) and these winds had significant turning with height.  This wind profile created a favorable environment for rotation in the thunderstorms that developed.

* Corresponding authors email addresses: Sam.Shamburger@noaa.gov and Roger.Erickson@noaa.gov.