Stiff Collar has a post on wool suitable for summer business clothes. He describes the characteristics of different wool fibers and how they are woven. Google Translate will help to a degree.* "La Laine Froide" literally means "Cold Wool". I assume that it would be translated as "summer-weight wool." Please correct me if that's wrong.
I find articles like this useful because, in addition to the information, it can be extremely hard to find sewing and tailoring terms in other languages.
*If you use Google Chrome, right click anywhere in the article and you will be offered the option to have the page translated. BTW, for "son" read "thread." The word "fils" in French is used for both and many articles for which I've used Google Translate have this problem.