This was a question on a re-blog, but I figured I would answer it.
I’ve read that a tornado is usually at its largest size upon touchdown. When is the Fujita scale used?
So, first things first. Tornadoes are not particularly larger/stronger when they initially touch down. They can change greatly over their life cycle in strength, size, and even go as far as to touch down multiple times.
The Fujita Scale that was first created was a 13 level scale that was based strictly on wind speed. This scale has since been retired in favor of the Enhanced Fujita Scale. The new scale examines damage and determines the EF value (of 1 through 5) of a tornado after proper assessment.
At this point I’m sure you’ve heard about the Tornado in Oklahoma yesterday. Here’s the hook echo from that storm.
Finally have internet and a comfortably sized queue lined up for you guys. Party on, Wayne.