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THE MAJOR TORNADO OUTBREAK ACROSS SOUTHEAST TEXAS AND SOUTHERN LOUISIANA - STORM ASSESSMENT

Robert B. Darby & Raymond J. Sondag *

Weather Forecast Office
Lake Charles, Louisiana

INTRODUCTION

On the night of January 1-2, 1999, Southeast Texas and Southern Louisiana experienced one of its biggest tornado outbreaks in recent history. Fourteen tornadoes occurred across the area, one reaching F3 intensity on the Fujita scale. Five F2 tornadoes also occurred during the event. The last time an outbreak of this magnitude occurred in Southeast Texas and Southern Louisiana was on November 7, 1957, where eight tornadoes struck, five of which were F3 intensity or higher.

During the evening hours on January 1, 1999 a strong upper level disturbance moved into Southeast Texas. In conjunction with this feature, a surface low developed over North-central Texas with a strong cold front extending southward. Ahead of the surface low, a low level jet developed with strong veering winds in the lowest levels of the atmosphere. Warm, moist air from the Gulf of Mexico moved onshore causing the atmosphere to become increasingly unstable. The strong low level winds and increasing instabilities set the stage for a series of strong rotating thunderstorms.

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. (The star symbols on the high resolution maps indicate where damage occurred from the tornado.)

Map of tornado damage tracks across the Lake Charles warning area

NATIONAL WEATHER SERVICE MODERNIZATION PROGRAM

The National Weather Service (NWS) is fast approaching the completion of its multi-billion dollar modernization program. This has led to the first nationwide network of Doppler weather radars (WSR-88D) and a new state-of-the-art computer system (AWIPS). This network is used by the NWS to protect life and property by issuing timely and accurate tornado and severe thunderstorm warnings. Unlike the old radar, the WSR-88D has the ability to remotely measure wind speeds inside a thunderstorm. This gives the forecaster an indication of whether the storm may become tornadic or produce strong damaging winds. The tornado outbreak sited below is an excellent example of the radar's ability to detect the potential for tornadic storms and thus provide advanced warning to the public.

PRODUCTS ISSUED BY THE NATIONAL WEATHER SERVICE IN LAKE CHARLES

The following are the products issued on January 1, 1999, advising the public of the potential for severe weather.

0455 AM CST - Special weather statement
0458 AM CST - Flash flood statement
0223 PM CST - Special weather statement
0455 PM CST - Special weather statement
0737 PM CST - Special weather statement

Listed below are tornado warnings and statements issued on January 1-2, 1999 during the outbreak. The tornadic thunderstorms began during the late evening hours on the 1st. and continued through the early morning hours of the 2nd.

Of the 18 warnings issued, all verified with either a tornado touchdown or damaging downburst winds. There was only one missed warning, where straight line winds caused damage to a few homes and sheds in the communities of Anacoco and Hornbeck in Vernon Parish. All of the tornadoes were radar indicated by the WSR-88D radars in Lake Charles and Fort Polk, Louisiana. Average lead time on the tornado warnings was an impressive 24 minutes. (Note: lead time is defined as: the time between the issuance of the warning and actual tornado touchdown.) However, because the majority of the tornadoes occurred in the middle of the night, many residents were sleeping, without any knowledge of the imminent danger. Persons who owned a NOAA Weather Radio, with an alert feature, would have received the tornado warnings as soon as they were issued by the NWS. This would have alerted them to seek shelter from the storms before they hit. Unfortunately, one fatality occurred in a mobile home near the community of Buna, Texas. Given the severity of the tornadoes and the time of occurrence, it is fortunate that more people were not seriously injured or killed.

SUMMARY

Storm data from this event will continue to be compiled and is subject to change. Additions / revisions may be needed as more information is received. Persons with additional information concerning the tornado event can contact the NWS at the address listed below or call (318) 477-5285. An updated storm assessment will be posted once the official survey has been completed.

Acknowledgments: The authors would like to thank Roger Erickson (Warning Coordination Meteorologist) and Tim Erickson (Meteorologist Intern) for the tornado damage pictures and their extensive post-storm surveys after the event.

* Corresponding authors address: Robert B. Darby and Raymond J. Sondag, NWSO 500 Airport Blvd. #115, Lake Charles, LA 70607; e-mail: Robert.Darby@noaa.gov or Raymond.Sondag@noaa.gov.

*Authors' current affiliation: National Weather Service, Tulsa OK

Page last modified: June 4, 2003