Nikki Hjorth turned Monday into “a Marvel movie day” with her kids. Julie Sobchack did chores and cheerfully planned some baking. Alyssa Smith celebrated her “first snow day as an adult” by relaxing and shoveling — as each was among the thousands of Utahns who unexpectedly found themselves spending the day at home amid a major snowstorm.

Not everyone was happy to add an extra day to their kids’ weekend — or their own. Jaime Cross Carroll was “attempting to get some continuing education units done with interruptions every five seconds.” And Bill Lines was “freaking out about not being able to get to the job site. It’s how I get paid. And pajama bottoms and Netflix won’t pay the Netflix bill!”

The storm’s hazardous driving conditions shut schools and had many workers opting to telecommute, as the Utah Highway Patrol responded to 313 crashes as of 3:45 p.m. And in the Salt Lake Valley, the snow just kept on falling.

More than 18 inches of snow had piled up in Cottonwood Heights, 17 inches in parts of Sandy, 16 inches in areas of Midvale, 15 inches in Holladay, 14 inches in parts of Salt Lake City’s Sugar House, and 12 inches in Murray, Taylorsville, Millcreek and West Valley City, as of 1 p.m., according to the National Weather Service. Also as of 6 p.m., Salt Lake City International Airport had received 9 inches of snow. As of 4:53 p.m., 8.6 inches were on the ground there, breaking a 24-hour snowfall total from 1936 by 1.6 inches.

Tuesday morning’s commute is expected to be better — but that doesn’t necessarily mean it will be good. According to the weather service, a winter storm warning remains in effect for the Salt Lake City area until 4 a.m. Tuesday, with winds gusting to 35 mph and additional “heavy snow.” The precipitation is expected to end and the sun will reappear, but after an overnight low of 11 degrees. Tuesday’s forecast high is 25.

And there’s a 20% chance of snow on Wednesday; that goes up to 70% on Wednesday night.

On Monday, the Salt Lake City School District took the rare step of canceling classes — one of just two snow days in the district in at least 19 years — and the Canyons, Alpine, Juab and Nebo school districts also shut down for the day. The University of Utah and Salt Lake Community College scrapped morning classes and planned to open midday, then decided to remain closed as the snow continued. (Utah State University stayed open in Logan and so did Utah Valley University in Orem, drawing some complaints from aggrieved Aggies and Wolverines.)

Quinn Rollins, a teacher at Cyprus High School in the Granite School District, tweeted a photo Monday morning of the Magna school’s student parking lot, which was empty of cars but full of snow at the time classes were supposed to start.

The district, noting that many students would arrive at school no matter the conditions, scheduled a late start and said it would “be providing a safe warm environment for any and all that come.”

“No day off for me,” wrote kindergarten teacher Kelli Wendlandt, one of The Salt Lake Tribune readers who shared their day’s plans in response to a query on Facebook. “I enjoyed shoveling myself out and going to work” at Gearld L. Wright Elementary in West Valley City. (“Enjoyed” may have been a little sarcastic. At least about the shoveling.)

It took Taylorsville High teacher Lisa Shafer “an hour and 15 minutes of white-knuckle driving to get to school, and so far I’ve had a total of four kids show up,” she posted at midday.

In the hilly Avenues area of Salt Lake City, Utah Transit Authority buses were unable to reach routes above 3rd Avenue early Monday. TRAX and FrontRunner trains were experiencing delays, UTA officials warned. Anne Rudd Shaw spent “2½ hours on a TRAX train” before she “finally” made it to work, she posted, one of many who couldn’t telecommute and had to travel.

All state offices delayed operations until noon, Gov. Gary Herbert announced. Other places that chose late starts included state courts, offices of The Church of Jesus Christ of Latter-day Saints in the Salt Lake City area and City Creek Center in downtown Salt Lake City.

Salt Lake County Mayor Jenny Wilson, via a tweet, announced that all nonessential county offices would be closed Monday. The Salt Lake County-run Clark Planetarium at The Gateway was closed, as were all Salt Lake City Public Library locations.

Utah Media Group, the company that prints and delivers The Salt Lake Tribune and the Deseret News, sent an email to subscribers, warning of possible delayed delivery of Monday’s print editions. “Looking for my paper buried in the morning snow,” subscriber James Wood wrote on Facebook. “Oh well, the coffee was good.”

The extra time off allowed some Utahns to catch up on current events — whether they liked it or not. After “watching my husband shovel snow,” Rebecca Richard said, she turned on the TV and started “wishing coverage of the impeachment wasn’t still dominating broadcast television. It’s so heartbreakingly depressing it’s causing me to forget yesterday’s Super Bowl fun.”

For Alex Gallegos Ruybal, the timing of the storm was good. And bad. “Cleaning my house after a huge Super Bowl party mess,” she wrote. Great! “While my children are home,” she added. OK. Not so great, according to her not-so-happy face emoji.

The Utah Department of Transportation issued a driving advisory for much of the state’s central corridor until Tuesday. UDOT officials anticipated dangerous driving conditions on Interstate 15 from the Idaho border to Cedar City; all of Interstates 84, 80 and 70; all of U.S. Highways 40, 89, and 191; and all of State Road 20. Chains or four-wheel drive were required in Big and Little Cottonwood canyons.

Meanwhile, the Utah Avalanche Center warned of elevated likelihood of avalanches in the mountains, foothills, benches and steep terrain statewide from the Idaho border through Utah County.

So if retirees were a little smug about not having to travel in Monday’s conditions, well, who could blame them? “I’m retired from the Army,” posted Scherome Harris. “Enjoying my coffee and my dog."

“I paid my dues commuting. No more!” wrote Mary Jane Jones. She did, however, start posting that she’s “ready for summer” on her Facebook page … back in early December.

Salt Lake Tribune reporter Sean P. Means contributed to this story.