How (at what rate), does wind speed increase with altitude?

Question

Let's start at 10,000 feet, then 20,000, and stop at 40,000.

Answer 1

Near the surface, it increases logaritmically with height. This goes on as high as the surface effects can be "felt", which can be roughly untill 1000 m, or 3000 ft. Above that, many other factors matter, such as the horizontal temperature gradient.

Typical values (planet averages) would be:

5 m/s at 10000 ft,

10 m/s at 20000 ft,

15 to 20 m/s at 40000 ft.

Off course, it is all highly variable. In a jet stream, for instance, it can reach 40 m/s, easily.