A winter storm dumped 3 to 6 inches of snow across much of the Four Corners early Thursday, resulting in difficult driving conditions for commuters and closing schools in northwest New Mexico.

For the most part, roads remained open and the highway system was functioning as normal, said Lisa Schwantes, a spokeswoman with the Colorado Department of Transportation in Southwest Colorado.

However, U.S. Highway 160 was closed about 5 miles south of Cortez Thursday morning from about 5:30 a.m. to about 8:20 a.m. after a semitractor-trailer jackknifed near mile marker 31, Schwantes said. The front hill leading to Fort Lewis College in Durango was also closed.

Law enforcement responded to several minor traffic crashes.

Snow also impacted Farmington and Northwest New Mexico. This would be the first major snowfall in winter season.

Several inches of snow accumulated on U.S. Highway 491 between Shiprock and the Colorado state line, slowing car and truck traffic to 25 mph in places.

According to Devin Neeley, public information manager for San Juan County, the winter storm brought 4 or 5 inches of snow to the area.

Snowplows from the New Mexico Department of Transportation were on call since midnight, plowing and treating roads, said public information officer Jim Murray.

All the snowplows were out Thursday morning, according to Murray. He estimated between 10 to 20 snowplows were out in San Juan County. Shiprock has six plows. Farmington and Bloomfield have at least six plows.

“Those two are pretty big patrols because they cover a wide area,” he said.

When Murray spoke with Michael Mayo, City of Farmington patrol supervisor, he said the roads were pretty bad at 7 a.m.

“It’s a lot of roadway to cover up that way,” Murray said when it came to the snowplow activity that morning.

U.S. Highway 64 is the main focus of snowplow efforts. Other main highways are U.S. 550 and 491, Murray said.

Murray emphasized the activity of the snowplows and if they were not seen on one road, they would be working to clear others.

“The more lanes the better,” he said.

Farmington Assistant City Manager Shana Reeves said the city of Farmington began maintaining roads at 5 a.m. Thursday and shifted its focus to “small routes” at 1 p.m. Thursday.

“Local streets will be addressed over the next few days and weeks,” Reeves said, adding that another winter storm is expected to hit the region Sunday. “If that occurs, it may reset our cycle.”

Harper Hill, on U.S. 64 on the city’s western edge, was closed until 8:30 a.m. Thursday. “People were not able to get up the hill,” said Farmington Police spokeswoman Shanice Gonzales.

Several roads in Farmington were closed while Farmington Police Officers responded to crashes. The intersection of Piñon Hills Boulevard and North Butler Avenue was closed because of an crash with minor injuries, Gonzales said.

There also were crashes on Apache Street and at Apache Street and West Main Street. “It was super-busy this morning,” Gonzales said.

New Mexico State Police also were busy.

“There have been at least a dozen motor vehicle accidents in San Juan County, Rio Arriba County and Taos County since 6 a.m.,” said State Police officer Kyle Lee, who works in the northern region of the state.

The San Juan County Sheriff’s Office responded to 16 motorist assists and three accidents.

“There were no major injuries,” said Mathew Chavez, spokesman for the Sheriff’s Office.

Schools in San Juan County are closed

Farmington Municipal Schools, Central Consolidated, and San Juan College canceled classes on Thursday, and Aztec Municipal Schools switched to remote learning.

Bloomfield was on winter break and was scheduled to return Jan 5.

Aztec’s decision to move to remote learning comes after 2023 legislature, House Bill 130, required an increase in hours of 990 in elementary and 1,080 in secondary to 1,140 for all students, Kevin Summers, Aztec Superintendent said.

“That being said, cancellations for snow are no longer a possibility; otherwise students would have to make up missed instructional time, which would require students and staff to return after Memorial Day,” he said. “Hence, we opted to preserve instructional time during inclement weather by opting for either a two-hour day or a remote/virtual day.”

According to the FMS website, the district does not hold remote learning with school closures because of inclement weather. FMS will make announcements the night before or by 5 a.m the day of.

San Juan College closely follows FMS weather delay and closure procedures, according to Boomer Appleman, vice president of student services.

“At San Juan College, or top priority is the safety and well-being of our students and dedicated employees,” Appleman said in an email.

According to Central’s inclement weather procedure, the district starts with a road check at 4 a.m. The superintendent will receive a recommendation from the transportation coordinator by 5:30 a.m., and by 6 a.m., an announcement to parents is made.

Jerrod Noble, public relations supervisor, said a transportation team of four made went out to make a report at 4 a.m., and at 4:55 a.m., a recommendation from the transportation coordinator was made to Superintendent Steve Carlson.

Central schools will make up for the snow day in March, Noble said. In the past, Central had moved learning to remote during inclement weather.

“Snow days are awesome,” he said “We don’t do remote days anymore, we want to do snow days.”

Senior centers in Aztec and Blanco closed, along with the Riverview Golf Course.

“We get about better than 300 days of golf out there a year, and I was out there last week and it was about 17 degrees. And they had, I think, four or five foursomes on the course. So the only time we close it river view is if there's snow on the course,” said Neeley.

Neeley said six county plows worked on major roads beginning about 5 a.m. “They will continue until the weather improves,” Neeley wrote in a text.

Purgatory Resort and Wolf Creek Ski Area both reported 3 inches from overnight snowfall as of 10 a.m.

Schwantes described road conditions as slushy or mushy in Durango and more hard-packed north of town as the elevation increased.

She said crews were “out in force.”

CDOT crews were reporting 3 to 6 inches on the mountain passes as of 6:30 a.m., “and it’s obviously still snowing out there,” she said.

All schools in La Plata County School District were open. In Montezuma County, schools remain on winter break until Dec. 9 in Montezuma-Cortez School District RE-1, Dolores School District RE-4A and Mancos School District RE-6.

U.S. highways 550 and 160 over Wolf Creek Pass remained open as of 10:30 a.m. Thursday.

Shane Benjamin and Tyler Brown of the Durango Herald and David Edward Albright of the Tri-City Record contributed to this article.