Winter storms on Tuesday blanketed Southwest Colorado, dropping 6 inches of snow in Dolores and Mancos, and more than a foot on mountain passes.

A winter storm that began Monday afternoon and evening stretched into Tuesday largely followed predictions from the National Weather Service. A second storm Tuesday evening is expected to more than double snow totals and leave travelers facing blizzard conditions in places.

“I think it’s pretty much on track,” said Kris Sanders, a meteorologist with the National Weather Service based in Grand Junction. “The Durango-Cortez area saw anywhere between 2 to 6 inches, so not too far off track.”

According to Jim Andrus, a weather watcher in Cortez for the National Weather Service, said snow began falling about 7:30 p.m. Monday, and by 8 a.m. Tuesday, central Cortez had received 4.6 inches.

The weather service predicted that the storm would bring 5 to 12 additional inches of snow to the area by Wednesday evening, and issued a winter storm warning in effect until 5 a.m. Thursday. Winds are expected to reach 45 mph.

Dolores received about 6 inches of snow, and Mancos, 5 to 7 inches, depending on elevation. Durango received 2 to 4 inches of snow, and Pagosa Springs, 1 to 3 inches.

“This sounds like this could be our biggest storm in many years,” Andrus said Tuesday morning, “and a chance to build up our spring snowpack.”

Andrus reported that snowfall for Cortez was 67% of normal, with 16.7 inches by Feb. 22. Cortez received 10.6 inches in January.

Andrus measured Tuesday morning’s snow water equivalent to be 0.27 inch of precipitation, and predicted that it would rise to 0.5 to 0.6 inch of precipitation by the end of the storm.

He described the storm as a strong jet stream parked over the Four Corners.

“It’s good, strong jet stream, and that’s why the weather service has issued a storm warning, with 4 to 8 inches of snow Tuesday and Wednesday night,” he said.

Because the storm will bring strong winds and low visibility, he advised people to sit it out at home.

Empire Electric Association had a quiet night, said Mike Wofford, chief system operator at the utility. An outage was reported late Monday night along the Dolores River north of Dolores but was resolved in the “wee hours of the morning,” he said.

Roads in Southwest Colorado were snowpacked north and east from the New Mexico and Utah state lines.

Snowy road conditions stranded five semitrailers on U.S. Highway 491 Tuesday morning, said Montezuma County Sheriff Steve Nowlin. A portion of the highway through Dolores County was temporarily closed.

“It has all been cleared and the highway has reopened,” Nowlin said.

He said there were numerous slide-offs around the county, including on U.S. Highway 160 at Mancos Hill and mile marker 7 on Colorado Highway 184. There were no reports of injury crashes.

Road conditions were snowpacked and slushy in the Dolores area, and wet farther south, Nowlin said. Snowfall is expected to continue Tuesday, and roads were expected to become icy Tuesday evening.

Montezuma-Cortez, Dolores and Mancos schools delayed classes by two hours.

Commercial chain laws were in effect from U.S. Highway 491 at the Utah border across parts of Southwest Colorado. Chain laws also were in effect on Colorado Highway 145 from roughly Telluride south to Lizard Head Pass north of Rico.

Mancos Hill and Hesperus Hill along U.S. Highway 160 east of Cortez were snowpacked, and icy in spots.

The storm hit a wide swath of Colorado, slowing traffic on U.S. Highway 550 north of Durango, as well as on I-25, I-70 and U.S. Highway 285, according to the Colorado Department of Transportation.

in the U.S. 550 corridor, CDOT planned avalanche mitigation on Coal Bank and Molas passes, south of Silverton, beginning at 10 a.m. Wednesday. Crews will attempt to allow traffic through periodically. CDOT also planned mitigation work at Red Mountain Pass and expects operations to last through much of the day.

The Colorado Avalanche Information Center reported that the risk of avalanches was “considerable,” or Level 3 of five levels. Monday, the risk level was at “moderate,” or Level 2.

According to CAIC, Coal Bank Pass, along the U.S. 550 corridor, had received 12.4 inches of snow by morning.

Telluride received 11 inches of new snow from the storm, and Purgatory received 14 inches.

As of Tuesday, combined totals for five SNOTELS that measure snowpack in the Dolores River Basin showed 90% of normal, up from 89% on Monday. The Animas River Basin snowpack is at 87% of normal.

The SNOTEL stations for the Dolores Basin are located at El Diente Peak, Lizard Head Pass, Lone Cone, Scotch Creek, and Sharkstooth.

Winter season snowpack statewide was 90% of normal as of Feb. 22, according to the Natural Resources Conservation Service.