Note the difference between Pathlines and Streamlines and keep in mind that what you see is not an animation of the actual air movement:

https://www.youtube.com/watch?v=OLSmNZm1e0k&feature=youtu.be...

Harvey has dissipated more-or-less, the one near Mexico is Hurricane Kattia

Compare https://www.ventusky.com/?p=19.6;-77.9;4&l=wind&w=0xIAb9A9A

That’s my new favorite.

It’s interesting how the wind appears to spiral into the eye near ground level, and out from the eye at 12k meters.

It’s like there is a toroidal shape where on the bottom, wind spirals in towards the eye, transitions to the top in the eyewall and spirals out at the top.

"rising air in the eyewall follows isolines of equal angular momentum, which [also] slope outward with height" (Wikipedia)

partial to windy.com myself

https://www.windy.com/?20.633,-75.498,5,a:q3iI3

Whatever that last parameter is on the url, it causes mass rendering artifacts in Firefox/Linux. It works for me w/o.

https://www.windy.com/?20.633,-75.498,5

Is this derived from http://hint.fm/wind/ ?

Also, does anyone know how that elbow in the path forecast comes about? Is there something magical about the waist of Cuba that suddenly makes it turn north?

"Because of the passage of an upper-level trough to the north, with Irma starting to feel the steering effects of the westerly flow of the midlatitudes." Described in detail with figures here: http://cliffmass.blogspot.com/2017/09/american-versus-europe...

High pressure areas to the west.

*Katia

A fun aspect of this site is that you can change the map projection used.

Not sure if this is some display artifact, but the most striking thing to me is how strange the wind patterns are in many parts of North America if you zoom out.