several hours
The Tuscaloosa-Birmingham tornado of 2011 was on the ground for about 90 minutes.
The average time for a tornado to stay on the ground is around 10-15 minutes, but they can last anywhere from a few seconds to over an hour, with some particularly long-lasting tornadoes staying on the ground for hours.
The duration of a tornado can vary greatly, from just a few seconds to several hours. The length of time a tornado stays on the ground depends on various factors such as the speed at which it is moving, the strength of the tornado, and the terrain it encounters.
One tornado is reported to have had a damage path only seven feet long. It was likely on the ground for less than a second.
several minutes or hours
It was on the ground for about 30 minutes.
The worst tornado in U.S. history, the Tri-State tornado of 1925, was on the ground for 3 hours and 29 minutes. The worst in world history, the Daulatput-Saturia tornado of 1989, had a path length of 50 miles but it is not known how long it was on the ground. However, given the path length it was probably on the ground for an hour to two hours.
The Hallam tornado was on the ground for 1 hour and 35 minutes.
A tornado that does not touch the ground is a funnel cloud.
There is no set size for a wedge tornado. Generally a wedge tornado is one that appears to be wider than the distance from the clouds to the ground and the height of the clouds can vary.
The average tornado lasts about 10 minutes. However, duration can vary greatly. Some tornadoes last only a few seconds. In rare cases a tornado can be on the ground for an hour of more. The infamous Tri-State tornado of 1925 is believed to have been on the ground for over three and a half hours.
A space tornado can cause serious damage, usually 2-4 miles wide if it touches ground. But most of the time, it doesn't touches ground