Skaters, Bull Whips, Tornados, Hurricanes, and the Mother of Cyclones

We all have seen how an ice skater enters a slow twirl and accelerates the rotation by bringing her arms in close. That's basically conservation of angular momentum. When her arms are outstretched, the mass is farther from the center of rotation. As the arms move in, the mass is more centralized and has to spin faster to maintain the same momentum. 

That phenomenon is part of what makes a whip "crack". A loop of decreasing radius travels down the whip, and at the end it is rotating very fast, resulting in a pop or cracking sound (and a painful touch if you are there at the end).

A tornado is formed when a column of air begins to rotate. The column begins to have negative pressure compared to outside, which shrinks the column, which makes the rotation speed up, which creates more negative pressure, and pretty soon it can suck up an entire house with a young girl and a dog inside and deposit the whole caboodle in Oz. The negative pressure is caused by air squirting out of the top of the column.

Tornados are often spun up in the "arms" of tropical storms. These arms are acting like big bullwhips and spinning off vortices as they crack.

There is a well documented thing called the Central American Gyre, a huge low pressure system that hovers over central America and the western Caribbean in late summer. This system slowly rotates, hence "gyre". This relatively slow rotation has "arms" too, and these generate large spin-off vortices. Most of these just spin away, but some begin to consolidate (shrink and hence speed up, like the skater). These consolidated vortices can become tropical storms and leave the Gyre as independent entities. We even make up names for these children. The Gyre is the mother of (many, but not all) tropical storms in the western Caribbean. She spawned Helene, and maybe another one soon.