Did it last year on a windless sunny day. Still bloomin' cold at the top and on the way down. It's not steep like steep is here in the uk, what it is, is long.
Don't cycle head down all the way up and down, take it a bit slower and enjoy the views, the views over Provence are superb. There are so many cyclist riding up (and down) there that seem to be head down all the way, battering themselves. OK if you live nearby and can do it again, but if you aren't likely to be doing it again any time soon, take it all in and enjoy it. I rode it with two others who where a good half an hour quicker than me, I don't think they stopped at Simpsons memorial or looked up from the road all the way up.