varies, you should ask the host. i think where i take it is 85-95 depending on the instructor... one is far more challenging, and even puts the fans on much very low so you feel it more. with another instructor, it is just cozy-warm, with the heat not very challenging in itself. with her class, i will sweat constantly, but not as profusely as with the other, where i cannot take the class without an added "yoga towel" on top of the mat because my dripping sweat makes a grip on the mat impossible. attractive...
but "bikram" style yoga is *very* hot, more like a sauna... some contend dangerously so, while others are rabidly devoted to the style. i have never tried it. it would be too much for me at this level of my ability...and perhaps at any level.
Actually... Yes I do like it. The only thing that keeps me from doing it more is that they are hell bent on every pose being a pole straight leg and locked knee. There is no such thing as a straight but soft knee. They actually say "Lock it. Pull it in tight. Straight like a lamp post." And to me that is the absolutely the worst thing for my knees and my chondra malacia. Other than that I love it and if I had a studio (with a shower) close to work I would do it several times a week. As it is now I simply go on a day off once in awhile.
well, that is actually very encouraging to hear... aside from the straight leg business. i shall bear that in mind. but at the moment, i'm so not ready to try it out. i think i would collapse from that degree at heat.
i really enjoyed pilates and felt it helped but must admit i never tried yoga. I only stopped pilates because of difficulty finding affordable classes on during convenient times (i have a long commute daily, which takes a lot of time out of my day).