Light jacket/wind cheater, if it drizzle the one with hood or a hat is useful so you can snap photo. Check china weather forecast to be sure. Cable car up half way,toilet at stations ok, squat mainly.
It rained when I was there last week, did not see the snow capped mountain, nevetheless i did not allow that to affect me, there are many things to enjoy, nature provides many choices. One only has to set the right mind to accept any that avails. Have a good trip.