vegas in december

When I have been in LV in December, I have found the highs anywhere from about the 30's with the winds blowing as well to as high as about 70 or so. So I would encourage you also to go to https://www.weather.com and type in 89101 (which is the Zip Code actually for Downtown LV) for the zip code and you can get the current, 5 day and 10 day forecast so you can have some kind of idea on what to expect.

RecVPPlayer

I've replied in the past on my first Dec. trip in 1995, 10 years after my first visit in 1985, that it was so
hot out one day that I seen Santa Claus getting out of his car, 6'2" 135# skinny as a rail, as he was walking into the Fashion Show Mall, I was sweating just walking down the sidewalk, so it can be hot there as well. Also I also remember catching a cold out there on other Dec. visit.

I have gone to Vegas In Mid Dec numerous times and each time is different. Rain, snow, cold, hot. Good deals after the Rodeo. My husband wears short sleeved shirts with a light jacket or zip sweatshirt, I always wear long sleeves and a sweatshirt. Some times it is breezy or cool outside but heat on inside.... dress in layers if possible.
There are shuttlesfrom Gold Coast to Bill's and Orleans, and Rio to Harrahs, they run until fairly late, but not early before 9 or 10 AM.
Check out Shuttles tab at the top of the page. The only one I found long was the one to the Red Rock, limited time before shuttle back.

You may also inquire on an all city pass for the CAT (bus) they have a 24 pass and multiday pass.
You can get it near the Rio and get the crosstown bus back on the side street at Caesars,(Flamingo Blvd)
Ask on the transportation forum page.
MO