I live in Madrid where I have an Abies nordmanniana since last Christmas. It is doing well this summer, although it is on a container and needs lots of water. I have read that firs can't live many years on a container, so I am thinking about planting it on a countryside in Extremadura, Spain. I know firs are adapted to colder climates than southwest Spain, but maybe it is the best thing I could do to the tree. My question is if it will grow in good conditions there or if I should not even try. The good point is that (like I said) the tree looks fine after the hottest summer days are gone, though Extremadura climate is a little warmer in the summer, also less cold in the winter and something wetter than Madrid climate.
The higher the altitude you can plant it at, the better. Try to find somewhere above 1000m altitude if at all possible (best, about 1500-1800m). Can you find somewhere in the Sierra de Guadarrama? That would be a very good climate for it.