Fat Asian Baby

Ok. It's hot. Really, really hot. I think the French collectively have very strange internal thermostats. I'm not exactly sure how warm it is today, but the Fat Asian Baby is sporting a small tank top and skirt for maximum breathability and comfort and still sweating her ass off. However, on my way to the internet cafe, I observed many Parisians sporting, not only jeans but jackets and some of the stifling leather variety. What need, pray you, has any reasonable person for a jacket on a day that is reasonably sweltering in the sun. In New York, I can understand the need to port a jacket around with oneself due to the refridgeratorlike qualities of the subway, large stores, offices, etc. But aside from wearing jackets in the summer, Parisians do not seem to have caught onto the whole air conditioning craze. Have we learned nothing from last year's deadly heat wave?
The upshot of this heat is that it has encouraged the Fat Asian Baby to visit more museums because they, unlike almost everywhere else, seem to be at least feebly air conditioned.