The Four Corners area will see two waves of storms this week bringing strong and potentially hazardous winds, with the worst travel conditions expected in mountain areas Tuesday and Wednesday.
The National Weather Service has declared a winter storm warning for the Southwest San Juan Mountains from 11 p.m. Monday to 5 a.m. Thursday. The Colorado Avalanche Information Center has issued an avalanche watch for areas above timberline.
After a day of warmth, the National Weather Service projects a potent cold front and showers mainly in the mountains starting Monday evening. After the cold front moves in, the mountains will get a burst of snow, with conditions increasing from light snowfall to moderate and heavy snow combined with strong wind.
The storm warning includes the Southwest San Juan Mountains, Hesperus, Rico, Telluride, Lizard Head Pass and Red Mountain Pass until Thursday morning, with snow totals projected at 10 to 20 inches. With heavy snow and high winds, parts of the San Juans and Park Range are expected to fall into a high category of avalanche risk from Wednesday through Friday. Travel in backcountry avalanche territory is not advised.
The valleys are forecast for scattered showers and rain turning to slush and snow during the cold morning hours Tuesday. During the daytime Tuesday, the valleys will remain windy, with temperatures cooler but not cold, with highs in the low 40s.
Forecasters say during the first round of weather, valley snow totals remain uncertain but will be lighter than the mountains.
“Generally, we're looking at like a trace or a dusting up to like maybe three inches in the higher elevations. Mountains are looking at generally more during that time frame,” said Kris Sanders, a National Weather Service meteorologist.
Sanders said winds will accompany the system with gusts up to 45 mph in the valleys and much stronger in the mountains.
During a second wave Tuesday into Wednesday, snow levels will hover around 6,500 feet, meaning lower elevations are more likely to see slush or a light dusting. Areas above that could receive roughly 3 to 6 inches of snow through Wednesday morning, tapering off later in the day. In the latest forecast, NWS excepts Cortez to get 1-6 inches of snow.
The mountains will continue to accumulate additional snow.
“The mountains through the southern San Juans will generally see 1 to 2 feet of snow and gusts of 50 to 70 miles an hour. So any travel Tuesday and Wednesday through the mountain corridors will be harsh conditions,” Sanders said.
The valleys may still approach winter weather advisory level, he said, because high winds mixed with snow could reduce visibility and make travel harder. The chance of precipitation for Cortez on Wednesday is 90%.
“Even if it's not snowing, the wind is going to continue through that whole period,” he said. He said strong winds could lead to drifting snow and make it difficult for crews to keep roads clear, creating hazardous travel conditions especially on U.S. 550 and at Wolf Creek Pass.
While forecasters are watching trends for the early week’s systems, there is a chance of a third round of snow Friday. Sanders said current forecasts show those amounts aren't terribly high, but conditions could change.
The weather service is calling for dry weather this weekend.
awatson@the-journal.com
