Was just there a couple days ago, sounds like you get the last one of the year. Bring layers, especially a cap and gloves. it was only high 30’s up there despite being 55-60 on the strip. You’ll spend quite a bit of time out of the vehicle talking and learning, I think 75% of my group bought a knit cap in the morning.
I was there Dec 10th...it was coooold!! I had enough layers but there were others who were feeling it. Especially up top where they spend quite a bit of time talking about the bronco in the pavilion. Awesome team though!
Definitely dress in a lot of layers, gloves and warm hat! The overlook at the top of the camp was pretty chilly late in the afternoon after the sun went behind the mountain. Put the coffee at the base camp in your free Yeti and take a couple of the box waters from the fridge in the gift shop.
I was there the week of Thanksgiving. Great staff and a great time!