The low, at this point, is predicted to be 51F/10C on race day, 13C supposedly at 10pm (1). Montreal has the record at 5C. There are a lot of reasons to roll your eyes at the LV GP, this just seems to be the latest click bait trend. At least its not going to be 50C in the cockpit.
(1)https://www.wunderground.com/hourly/us/nv/las-vegas/date/202...
Edit: Here is an article from February saying the temp could be a concern, and listing all the ranges, https://www.meteomotorsport.com/2023/02/f1-2023-climatology....