Tornado Activity in the U.S. 1950-2007

This Demonstration maps and plots frequencies of all U.S. tornadoes and tornado-related fatalities and injuries from 1950 to 2007.


  • [Snapshot]
  • [Snapshot]
  • [Snapshot]


In "map" view, the relative number of events (tornadoes, fatalities, or injuries) for any specific state determines the intensity of its color. For example, the states with a higher number of tornadoes in the given time period will be more intensely red, while states with a lower number of tornadoes will be less intense or white. Note that the intensity of color for any state is based on a relative comparison to other states for that map selection only. In other words, a deep red for Mississippi when viewing fatalities in January does not necessarily indicate a higher number of fatalities than Illinois in April, which is a less intense red. Instead, it only indicates that Mississippi has a high number of fatalities in January compared to every other state in January.
In "plot" view, note that the general increase in overall tornado frequency since 1950 may be due in part to greater numbers of local spotter networks and radar.
All data was gathered from the Tornado History Project.
    • Share:

Embed Interactive Demonstration New!

Just copy and paste this snippet of JavaScript code into your website or blog to put the live Demonstration on your site. More details »

Files require Wolfram CDF Player or Mathematica.

Mathematica »
The #1 tool for creating Demonstrations
and anything technical.
Wolfram|Alpha »
Explore anything with the first
computational knowledge engine.
MathWorld »
The web's most extensive
mathematics resource.
Course Assistant Apps »
An app for every course—
right in the palm of your hand.
Wolfram Blog »
Read our views on math,
science, and technology.
Computable Document Format »
The format that makes Demonstrations
(and any information) easy to share and
interact with.
STEM Initiative »
Programs & resources for
educators, schools & students.
Computerbasedmath.org »
Join the initiative for modernizing
math education.
Step-by-Step Solutions »
Walk through homework problems one step at a time, with hints to help along the way.
Wolfram Problem Generator »
Unlimited random practice problems and answers with built-in step-by-step solutions. Practice online or make a printable study sheet.
Wolfram Language »
Knowledge-based programming for everyone.
Powered by Wolfram Mathematica © 2018 Wolfram Demonstrations Project & Contributors  |  Terms of Use  |  Privacy Policy  |  RSS Give us your feedback
Note: To run this Demonstration you need Mathematica 7+ or the free Mathematica Player 7EX
Download or upgrade to Mathematica Player 7EX
I already have Mathematica Player or Mathematica 7+