According to the forecast, daytime highs near 50 degrees F, night-time lows just below freezing (about 28 degrees F). As far as precipitation, it looks like (at this time) you have a very good chance of running into rain and/or snow during your trip.
Of course, given the rapidly-changing weather in mountainous regions, I would be prepared for colder weather than that. I would rather carry extra clothing and food 100 times and not need it than to not have it the one time I do need it.
I always like to check out www.weather.com before going to a new place. You can get the forecast plus historical highs and lows for a particular time of year. I hope this helps.
bernard