Esri has made an interactive map that lets you explore all the tornados that have struck the country from 1980 to 2012. Even Western Pa.’s small storms are plotted.
The Enhanced Fujita Scale uses wind speeds and damage indicators to calculate the severity of the storm. Since 1980, the country has suffered through 21 Category 5 tornadoes. Despite how much better forecasters have become at pinpointing paths of storms with the help of technology, the single deadliest tornado since modern-record keeping began in 1950 occurred only a few years ago. On May 22, 2011, 158 people were killed in Joplin, Missouri.
The worst that swept into our region appears to be the Great Pennsylvania Tornado of 1985, which solidified May 31 as the commonwealth’s deadliest day: As many as 21 storms tore through Western and Central Pa., killing 89, including 9 in Beaver and Butler counties.
You can play with Esri’s tornado map here.