Had our first frost last Thursday, the 17th of September, and again on Friday... don't know about Saturday or Sunday as I didn't get up early enough to find out.
But yesterday, the 21st we got about four inches of snow.
Today, as I drove home from work it started snowing and is snowing still... Winter Weather Advisory up from the NWS and the forecast is for 4-10.
Gotta love the Rockies.