An interesting piece on hurricane velocity

Note that a category 5 at minimum is twice the force of a category 3 at minimum. A category 3 at minimum is 2.2 times a category 1 at minimum. Since Irma’s velocity squared at its 185 mph maximum of 3.42 is twice the category 4 value of 1.69, it would have achieved Category 6, if their was one.

http://www.ec.gc.ca/ouragans-hurricanes/default.asp?lang=En&n=C95F66EC-1