4 mins
The Tuscaloosa-Birmingham tornado of 2011 was on the ground for about 90 minutes.
As of May 16, 2012 the last tornado was two days ago.
There is no given duration for a tornado of any intensity, but a tornado as violent as an EF5 will generally last fairly long. Most will likely last for at least 20 minutes. Some may last for well over an hour.
It varies. A tornado warning may last for just a few minutes or over an hour.
3.5 hours
The average tornado lasts about 15 minutes, but they can last anywhere from just a few seconds to several hours.
3.5 hours
3.5 hours
The Joplin, Missouri tornado of May 22, 2011 lasted 38 minutes.
The Tri-State tornado lasted for 3 hours and 29 minutes.
It was on the ground for about 30 minutes.
The Moore, Oklahoma tornado of 2013 lasted approximately 40 minutes.