Cold air will be pushing through Montana early Saturday morning and reach Wyoming by noon.  Bands of heavy or moderate snow will be impacting the Wind River Range of Wyoming Saturday and perhaps Red Lodge Mountain ski area in southern Montana (Wyoming border) by late AM.  Most snow will be falling east of the Tetons (Light snow possible).   Some snow is likely over the mountains near Big Sky, but amounts will likely be in the 2-5 inch range on Saturday. Heavier snow is going to be impacting interior Wyoming and will eventually be impacting Colorado Saturday night and Sunday.  If resorts were open, I would consider a chase to Red Lodge Mountain Saturday afternoon. Otherwise, most snow will fall east of most ski areas. 

Below: Cold air spreads into Colorado by early Sunday morning (New Mexico is still on the warm side). 

Colorado is in the spotlight for areas along and east of the Continental Divide for late Saturday and Sunday.  Models show the highest amounts in in the Pikes Peak region and the mountains south to the New Mexico border (10-14 inches).  Light snow (2-4 inches) is likely for resorts in eastern Summit County including A Basin and perhaps Loveland.  Winds initially from the north can be good for Winter Park and Eldora. Winds shift to the NE early Sunday which will decrease amounts along or west of the Divide (That will shut down snowfall for many ski areas).  I am not very bullish on this storm for areas west of Georgetown. The Front range foothills are likely going to see the highest amounts closest to Denver. Its possible a front range ski area will report 2-5 inches by Sunday mid morning but my confidence is highest along or east of the Divide. Rocky Mountain National Park may show higher odds.  Wolf Creek is open this weekend.  Some light snow is possible on Sunday with heavier snow falling south and east of the Ski area. 

New Mexico is a strong contender for heavy snowfall near the Colorado border favoring eastern ski areas. Taos is sitting on the fringe of heavy snowfall where Red River may benefit from being slightly east.  Its a tough call with winds from the N and NE.  Models show a decent chance of of 5-10 inches for these areas late Sunday through Monday morning. Ski Santa Fe sometimes does well with Easterly winds. If I were chasing look for the best odds on Monday morning with Taos on the wildcard list (Areas east of Taos might do better). 

Below: Cold air is well entrenched into New Mexico by late Sunday night. 

Below: Total snowfall through Monday night with 12-15 inches for Southern Colorado (Eastern side of the mountains) extending into northern New Mexico).  3-6 inches for Summit County. The Euro is less bullish for Summit County (2-5). 

Light Moisture may linger somewhat over New Mexico early next week.  Most of the Rockies will dry out with high pressure in control for the remainder of the week. Long term models don't look too exciting at this point.  There is a chance of a system impacting the west coast of California somewhere around October 23rd? These ensembles can change so lets hope it happens. 

Below: High pressure over the west (mid week map). 

Powderchaser Steve