12:10 PM MST, Wednesday, February 5, 2020
Heavy snow is likely Thursday and Friday in the mountains (and especially west-facing slopes). Amounts of 1-2 feet should be common. The heavy snow is likely to extend a few miles east of the continental divide with gusty northwest winds causing blowing snow in exposed areas and at high passes.
Front Range foothills and plains
This is not a classic upslope storm coming Thursday night and Friday. Instead we may see narrow bands of snow develop that are aligned from northwest to southeast (the direction of the strong upper level jet stream). The bands may be several hundred miles long but only about 20-30 miles wide. So while many areas might get 2 inches or less, there is the potential for 6-10 inches in a short time under one of those bands.
The best chance for snow bands appears to be in Larimer and Weld counties, and into the Cheyenne area. In those areas almost everyone should get at least 1-3″, with about a 30% chance for a period of heavy snow producing more than 6″.
The Denver-Boulder area also has a chance for heavy snow bands, but a lower chance. As you go south from Denver the chance for little or no snow increases.
This is a forecast with larger than usual uncertainty.
A look ahead: cold
After a dry day Saturday, there is another chance for snow Sunday or Sunday night. In fact, over the week that begins Sunday most or all days will probably have below-average temperatures with at least a couple chances for snow. It appears that nature is making up for a dry and mild December-January!