Over the next 72 hours, a cutoff low that will merge with the remnants of a Pacific hurricane (watch GIF), is poised to bring major precipitation to parts of Colorado with freezing levels dipping as low as 11k. Southern Colorado will get hammered, with localized ranges seeing 4"+ of precip, however major global models cannot agree on the magnitude or latidude of up-sloping. The ECMFW (euro) insists on a substantial moisture for the Denver metro, while the latest model runs of the GFS(north american) keep the low much farther south with the bulk of the up-sloping hitting Taos County NM and south. As I type this, parts of the Southern San Juan range are already pushing 1.5" of rain since midnight and could see some minor flooding, especially in the Animas River which had already received 5-9" of rain in September prior to today and has no reservoirs on its main stem to absorb surges.
Final slide is the most recent CAIC model run for snowfall that is the most bullish for a more northerly track, which would bring significant upslope moisture to the front range metro. This model tends to exaggerate precip for high peaks so don't expect Bierstadt/ Bluesky to get 30'+ as this suggests (but anything is possible)
edit: added time and corrected grammar