Was just at Crystal LakeWas there last weekend, Temps should be comparable.
Daytimes a very comfortable 60's with no wind. I walked around in a T-shirt, but needed my jacket on the bicycle. Night time and shade a bit chillier 45.
At 7'000+ it was quite a bit chillier and in the 40's(felt 50's)- but perfect for jacket as long as you kept moving. We definitely got cold sitting for very long.
Trails were clear of snow on all South Facing Slopes (which is most of Crystal Lake anyway) all the way to the top. On the back side of Windy Gap towards Little Jimmy, I encountered 5-6" of snow occasionally and also along the ridge towards Mt Hawkins and South Mt Hawkins above and around 8,000 feet. But the snow felt safe for the most part. If it got Icy, there could be some spots where you'd wish you had micro-spikes. Still those sections were few and far between and only along the ridge to South Mt Hawkins.
The road going up to Mt South Hawkins was treacherously washed out in three spots. Had I not been returning on that road, I might have turned back.
The cafe was open (I think they're only closed on Tuesdays- they have a FB page that you can check and by their regular updates you can get an idea of the weather conditions.)
There was NO ONE Camping when I was there- so PLENTY of room to stretch out. Especially if you hike into the loops where the gates are closed (totally allowable) and I found most of the spigots to be "ON" even if that section was closed- even in Deer Flats. Didn't try all the restroom doors though. They're often locked in sections that are closed.
The main camping section by the Cafe is all open and the bathrooms unlocked of course.