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How rare was Wednesday’s Onalaska twister? You might be surprised.

Sky 2 flies over tornado damage in Onalaska in Polk County.
Sky 2 flies over tornado damage in Onalaska in Polk County. (KPRC 2)

HOUSTON – We’re no strangers to tornadoes in southeast Texas. Wednesday’s twister in Polk County was a grim reminder of that fact. It was rated as high as an EF-3 tornado, with winds at 140 miles per hour, at one point during its track through Onalaska.

It was a strong tornado -- stronger than we normally experience in this region. But just how rare was it? The statistics may surprise you.

According to the National Weather Service Office for Houston/Galveston, southeast Texas has only recorded six EF-3 tornadoes since 1992. That’s less than once every five years!

Most of the tornadoes that develop in this part of the state are relatively weak EF-0 or EF-1 tornadoes. Since 1992, more than 500 of these smaller tornadoes have touched down here.

Winds from these tornadoes reach as high as 135 miles per hour. While they’re relatively “weak” on the Enhanced Fujita Tornado Intensity Scale (see below), they can do major damage and cost lives. The higher up the scale you go, the more deadly and destructive the twisters become.

Southeast Texas tornadoes are most often small on the Enhanced Fujita Scale.  Chart courtesy of the National Weather Service Office, Houston/Galveston
Southeast Texas tornadoes are most often small on the Enhanced Fujita Scale. Chart courtesy of the National Weather Service Office, Houston/Galveston

On a percentage basis, EF-3 tornadoes make up less than one percent of the overall total.

EF-3 tornadoes make up only one percent of the overall tornadoes that touch down in southeast Texas.  Chart courtesy of the National Weather Service Office, Houston/Galveston.
EF-3 tornadoes make up only one percent of the overall tornadoes that touch down in southeast Texas. Chart courtesy of the National Weather Service Office, Houston/Galveston.

EF-4 and EF-5 tornadoes are even rarer in southeast Texas. According to the National Weather Service, only two F-4/EF-4 tornadoes have touched down in the area since 1950.

  • Channelview Tornado, November 21, 1992.
  • Galveston Tornado, September 12, 1961 (Hurricane Carla).

No EF-5 tornadoes have ever been recorded in southeast Texas. Monster tornadoes in the EF-4 and EF-5 categories are more prevalent in “Tornado Alley." That region includes North and West Texas, Oklahoma, Kansas, Nebraska and parts of other Midwestern states. The deep south, including Arkansas, Louisiana, Mississippi, Alabama and Georgia, a region known as “Dixie Alley,” gets more of these large tornadoes than coastal Texas, too. EF-4 and EF-5 tornadoes pack winds in excess of 166 miles per hour!

The Enhanced Fujita Scale for tornado intensity.  Courtesy of the National Weather Service.
The Enhanced Fujita Scale for tornado intensity. Courtesy of the National Weather Service.

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