VORTEK LLC

OKLAHOMA CITY, OKLAHOMA REMAINS

THE MOST TORNADO-PRONE CITY DURING MAY

April 29, 2009

As part of an ongoing company-funded research study of tornadic risk assessment, by means of the Site Assessment of Tornado Threat (SATT) software*, VorTek has determined the rankings of the top twenty tornado-prone cities for the month of May. The rankings, based on National Weather Service data from 1950 through 2007, are as follows:
 

 

 

 

DISTURBED LAND

RANK

CITY

ACF (%)

AREA (ACRES)

  1

Oklahoma City, OK

0.0539

434

  2

Huntsville, AL

0.0382

307

  3

Lincoln, NE

0.0369

296

  4

Topeka, KS

0.0362

291

  5

Wichita, KS

0.0293

236

  6

Overland Park, KS

0.0291

234

  7

Kansas City, KS

0.0259

208

  8

Independence, MO

0.0234

188

  9

Lubbock, TX

0.0233

188

10

Minneapolis, MN

0.0216

174

11

St. Paul, MN

0.0205

165

12

Kansas City, MO

0.0193

155

13

St. Louis, MO

0.0164

132

14

Tulsa, OK

0.0155

124

15

Springfield, IL

0.0140

113

16

Perioa, IL

0.0140

113

17

Houston, TX

0.0139

 112

18

Birmingham, AL

0.0125

100

19

Pasadena, TX

0.0118

 95

20

Sioux Falls, SD

0.0112

90

 

The ACF "Annual Coverage Fraction" represents the average fraction of land area within a 20-mile radius of the city disturbed by tornadoes during May for the 58-year period from 1950 through 2007. The "disturbed land area" represents the average number of acres of land within a 20-mile radius of the city disturbed by tornadoes during May for the same 58-year period.