Malcolm M
Enthusiast
The word "veering" on its own means the wind is changing in a clockwise direction, and "backing" means it is changing in a counterclockwise direction. The actual definitions of the words are simple and contain nothing about easterly vs westerly or height or time.
Context is what sometimes makes it ambiguous what someone is trying to say when they use those words. When people are talking about hodographs - which show change in the wind with respect to height - and they say "veer" or "back", they mean clockwise or counterclockwise change in wind with respect to height. In the northern hemisphere, veering with height is favorable for tornadoes.
Another situation in which these words are mentioned often is when looking at surface wind maps over time. In the northern hemisphere, when you're in an open warm sector and the surface wind backs with respect to time, the environment is probably becoming more favorable for tornadoes - shear, SRH, and convergence are all increasing. This usually happens with a deepening low pressure system. And because of the way tornadoes usually happen here in the US, "surface wind backing with time" often means that the wind is changing from southwesterly to southeasterly. That's why people sometimes say that southeasterly or easterly winds are "backed".
