Even in July/August? We'll be up there just for the day and don't plan on any other high altitude mountaintop stuff (other than hiking in Slovenia for several days, but it's lower altitude where we'll be I think).
How cold is the Dachstein ice cave? Literally freezing?
I think it is barely above 32 degrees during the summer, which is what keeps the ice formations from melting during the summer. Surfaces like handrails are very cold to the touch, so you need good hand protection. No wind though!
We've been in several caves, but never an ice cave, so for us it was a very neat experience.
You're inside less than an hour.
Mountain altitudes - temp drops 3 degrees for every 1000 feet. The higher you go, the more exposed you are to the elements, so wind can also be a huge factor. The peaks have perpetual snow. High mountain weather is highly variable.
We were there in mid September. I remember being happy to be wearing my parka up on the peaks even though it wasn't that windy. Maybe if you put on enough layers, have a decent windbreaker, have something to cover your ears, hands, and a scarf (neck) you'll be fine.
There are a ton of discussions on hiking difficulty, clothing, the experience overall, etc. on trip advisor and other forums. So you can get a good idea by reading a bunch of these. We went in 2014, so it's already been several years. Boy - the cable car rides were just awesome!!!!
We arrived in Munich on Sept 1, and the trees were already starting to turn, and it was coolish, so even though we didn't need our Polartec mittens and head coverings, the parka came in handy.
Salzburg in early September, however, was quite warm. It would have been nice to have an air conditioned room. Hot days, cool nights (but the rooms take all night to cool off without AC).
