Hello Sharon, considering the time of year, as well as the many places that will be visited on the tour, you can expect temperatures to range between 10 and 15 degrees celcius. In Wyoming it may fall just below 10 degrees, in Las Vegas, it may be close to 20 degrees. As for clothes, I would avise you to prepare for both sunshine and a bit of rain. I do not think you will encounter any snow or serious weather conditions. Be sure to pack long trousers, short and long sleeved tops, and of course a water proof jacket.
I hope this information has been helpful and if you have any further queries then feel free to email me.
Kind regards
James, your editor