Colorado in early October

That early in Oct you're 99% likely to have great weather. The early winter storms that come through in Oct are usually short & light, and the little bit of snow dropped is all gone as soon as the sun re-appears the next morning. I live at 8500 ft and spend all summer & fall hiking & ATV'ing above 10,000 ft. I never head south to my winter home until the end of Oct. October is a transition month and is different each year, some years its clear, sunny & warm all month; some years winter makes an early arrival.
as noted, Monarch Pass is the only potential problem spot. Check the forecast when you get to Salida and overnight there if a winter storm is coming.