Published Saturday 2/13/21 at 11:30 am
Moisture has already started streaming into the forecast area resulting in light snow and flurries, to a mist in the lower elevations and light rain around Cortez.
The high-resolution NAM 3km model has been steadily increasing its event totals for the last 18 hours. This morning, the trend continued. If this high-resolution model is correct, my totals will be too low in the mid-elevations and the mountains.
Based on the latest model runs here are my forecasts. I am trying to be cautious with these totals, these are very conservative. I weighted the Euro very high, with its lower totals, when I put together these forecasts together.
These are grouped by snowfall totals, not geographically.
Montrose, Cortez, Marvel, Aztec: 2 to 4 inches after the rain changes over to snow this evening.
Durango, Bayfield, Ignacio, Mancos, Dolores, Breen, Ridgway, Ouray: 4 to 8 inches after the rain-snow mix changes over to snow late this afternoon or early evening. Higher accumulations are possible in areas at or just above 7,000 feet.
Pagosa Springs, and elevated areas along the HWY 160 corridor in Western Archuleta County: 7 to 10 inches.
Telluride, Rico and Silverton in town: 8 to 12 inches.
Mid-elevation areas including Durango West 1&2, Lake Durango, Rafter J, Long Hollow, Edgemont, Forest Lakes, Durango Ridge Ranch, Durango Hills below 7,700 feet: 8 to 14 inches with slightly lower amounts for Shenandoah and Trappers Crossing below 7,400 feet.
Mayday, Purgatory, Durango Hills at or above 7,700, Tween Lakes, Trew Creek, Los Ranchitos, Lemon, Vallecito above 7,700 feet: 10 to 16 inches. Higher amounts are possible in Mayday, Lemon, and Vallecito.
Wolf Creek: 12 to 20.
Here is the latest high-resolution 3km model run for total precipitation. I enlarged it as much as I could without distorting the image.
As you see this model is sniffing out some higher totals in the mid and high-elevation areas.
The medium-term models are slightly less reliable the day that the storm arrives because they are lower resolution. This just means they spread higher totals over the lower elevations. One of the best examples of this is Cortez. These models always struggle with Cortez because of the terrain around the area south and southwest of town.
The Canadian is the lowest resolution, next is the GFS, then the Euro with what would I refer to as medium resolution.
Canadian
GFS
Euro
The models are indicating the possibility of a lull very late tonight or in the middle of the night, then snow will continue throughout the day on Sunday.
Next Update Sunday morning, unless something comes up before then. Thanks for following and supporting the site!