Winter Storm in San Juan River Basin, Colorado

Generally 5 to 12 inches of snow fell across the area with 12.7 inches of snow reported at Pagosa Springs 1.6 SSW. More than half of the area received over 8 inches of snow. Winds gusted in the 25 to 50 mph range with a peak wind gust of 58 mph at Stevens Field located 3 miles northwest of Pagosa Springs with visibility less than a quarter mile at times in snow.

A low pressure trough digging southward down the west coast along with a 180 kt jet stream allowed a significant surge of Atmospheric River moisture along with strong southwest winds to advect into eastern Utah and western Colorado. This allowed for significant mountain snowfall across most mountains in eastern Utah and western Colorado where one to two feet of snow fell. Snowfall transitioned from a heavy wet snow with lower snow ratios in the early stages to an efficient power like snow with higher snowfall ratios due to the drastically changing temperatures. Some favored southwest slopes received up to three or more feet of snow as well. The strong jet allowed for strong winds and blowing snow in addition to the heavy snow falling with gusts in the 45 to 60 mph range on average across the mountains with some localized higher gusts above 70 mph. Due to the warm airmass, most lower valleys received rain or a mix limiting accumulations except the southwest Colorado valleys that saw a combination of heavy snow and blowing snow due to the wind once they received the colder air with a second shortwave and strong cold front towards the latter half of this three day storm event. There were also some snow squalls in some areas due to the combination of heavy snow, wind and low visibility at times with the passage of the strong cold front toward the latter half of the event.