The Fujita scale is a scale for rating Tornado intensity.
It is determined by meteorologists and engineers and takes into account a number of factors including radar tracking, eyewitness testimonies, damage imagery etc.
An F2 scale occurs 20% of the time and results in significant damage to houses and the environment. It is also seen as a life threatening event and Goverments all over the world spend millions of dollars on preventing loss of life and early warning systems.
The average speed of an F2 event is 180 - 250 kmh.
In New Zealand we call that a significant weather event, in Wellington they call it a storm.