The first major snowstorm of 2018 brought the Twin Cities to a halt Monday, stranding students at school and littering streets, alleys and highways with stuck cars.

Commuters on public buses got out and walked because it was faster. Hundreds of flights were canceled, keeping some Vikings fans in Philadelphia for an extra day.

In southern Minnesota, the National Guard was on standby to help and house travelers in need.

And Minneapolis and St. Paul both declared a snow emergency.

The storm walloped the southern half of the state, dropping up to 11 inches of snow in the Twin Cities.

It was the biggest snowfall since Dec. 12, 2012, when 10.5 inches fell in one day.

At Minneapolis-St. Paul International Airport, two runways opened shortly after 7 p.m. after being open only briefly earlier in the day, according to the flight tracking website FlightAware. The site said more than 560 flights into and out of MSP had been scrubbed and another 114 delayed as of about 9 p.m.

A Delta flight full of Vikings fans was stranded in Philadelphia. After already boarding once, pulling away from the gate and being told the airport had closed in Minneapolis-St. Paul, the plane returned to the terminal. Many fans ended up at a bar in terminal D, where sports were on TV, showing replays of Sunday's games. Fans commiserated about the sad loss and the ugly conduct of the Eagles fans.

"What are you going to do about it? It's snow in Minnesota," said Brent Groen, one of the stranded fans.

Panicked parents

Using a robocall, St. Paul Public Schools contacted parents just after 7 p.m. saying some students were still at school waiting for their buses to pick them up because of the weather.

Marsha Stoll waited for her sons, Joshua and Michael, to get home from Adams Spanish Immersion School for more than three hours. They should have been home by 4:40 p.m.

"I'm wondering if they are stuck on the bus in the ditch," Stoll said Monday night. The school told her the kids got on the bus at 5:30 p.m. but they didn't walk through the door until just before 8 p.m.

Toya Stewart Downey, a spokeswoman for St. Paul schools, said she was not sure how many students were stuck at their schools or affected by the delay.

She said the district did not close because officials did not expect so much snow.

"I'm hoping everyone is on a bus by now, but I'm not sure," she said just before 8:30 p.m. "I cannot say with certainty that every student is on a bus or home right now."

Both St. Paul and Minneapolis school districts canceled all classes and non-sports activities for Tuesday.

Downtown gridlock

In southern Minnesota, Interstate 35 was closed between Owatonna and Faribault, and Gov. Mark Dayton called out the National Guard on Monday afternoon to assist stranded motorists.

Guard spokesperson Blair Heusdens said they opened the Owatonna Armory to help travelers in the area. A team from Red Cross was also on site.

In the metro area, it took an hour to make the 24-mile drive from Stillwater to Minneapolis.

Traffic on Hwy. 36 was slow, with top speeds of about 35 miles per hour at 2:30 p.m. and whiteout conditions. It was much worse during rush hour.

The roads were choked with accumulated snow as much as 6 inches deep in spots in downtown Minneapolis. Making it through a stoplight took patience. Sometimes, no more than a car or two could make it before the light turned red because cars were spinning out in the snow and fishtailing through intersections.

In true Minnesota spirit, everyone pitched in, using shovels, trucks and their bodies to push stuck cars out of the deep snow.

Metro Transit buses had fallen behind schedule with 79 percent experiencing delays as of Monday evening, the agency said. Buses were jammed with riders but bogged down in traffic. Some buses on Hennepin Avenue moved only three blocks in 30 minutes, prompting some riders to get off and walk.

The storm dumped up to 11 inches of snow across the heart of the Twin Cities metro area with heavier amounts expected in the southern and eastern suburbs, the National Weather Service said.

Totals ranged from 4 to 7 inches in places such as Maple Grove and Rogers on the northwest side of the cities to a foot or more in places such as Cottage Grove, Cannon Falls and Red Wing.

The State Patrol responded to hundreds of crashes and spinouts. At least 30 semitrailer trucks had jackknifed, the patrol said.

The snow was especially hard-hitting because it fell in such a short period of time, often leading to whiteout conditions.

"This has been an interesting winter. We've been so dry," said meteorologist Alexandra Keclik with the National Weather Service's Chanhassen office. "Up until now we've been low on snowfall this winter and now we got this snow."

And while it caused havoc across the southern part of the state, she said it doesn't rate as the worst. "This storm is definitely significant, but I wouldn't call it 'snowmageddon.' "

Things are looking up. Temperatures should return to the low to mid-20s by Tuesday. Friday brings temperatures up to the 40s.

Frustrated Minnesota fans trying to get out of Philly got on the plane twice only to have to get off twice because of delays and ultimately, cancellation.

For one couple, the wait added insult to injury. Brent and Crystal Groen of Okabena, Minn., went sightseeing in Philly on Sunday and had to view the Liberty Bell through a window because of the federal government shutdown. After this weekend's fiasco of a game and antics of Philly fans, they say they don't imagine they'll be returning to town anytime soon.

As for the storm in Minnesota?

"I just hope they have it in about a week and a half," Brent Groen said, referring to the Super Bowl.

Staff writers Pam Louwagie, Pat Pheifer, John Reinan and Jeff Meitrodt contributed to this report.