Glenn, below is a link to U.S. Weather Service data that I found to be very helpful during our fulltime RV'ing life. Using this information makes it pretty easy to answer your question about Denver, as well as most any other city/area area of the U.S. It was really helpful for us when trying to decide where to go for the winter, and for other times of the year. I found that on the basis of this data, the Texas Rio Grande Valley is pretty hard to beat, for warmer weather, during the winter!!! lol
Just pick your state, and then pick a city, and you get the info you need. Of course, weather wise, what has happened in the past may or may not be similar to now and future weather events!!!!
http://countrystudies.us/united-states/weather/
Hope this helps you, and maybe helps others who don't have this site as a "desk top" shortcut!!
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