Major storm blanketing roads in snow, ice as travelers head home after holidays originally appeared on abcnews.go.com

A major storm is moving from west to east Saturday, leaving roads especially dangerous as travelers head home after the holidays.

The main impacts over the next 24 hours will be in the Plains and the upper Midwest. Winter weather advisories are in effect for cities including Denver and Minneapolis.

Freezing rain hit the Twin Cities Saturday, and police in Minnesota are warning drivers to stay home as dangerous ice covers roadways.

Statewide, there were 357 crashes between 5 a.m. and 10 a.m. Saturday, according to the Minnesota State Patrol.

Highway 36 westbound at Edgerton St in Little Canada currently blocked by a Bus Crash. Multiple Crashes due to Icy Roads are causing major traffic jams all over the Twin Cities at this time. Road conditions improve by Noon as air temperatures will be in mid 30s. @KSTP pic.twitter.com/PtJ34PeFxb — Jonathan Yuhas (@JYuhasKSTP) December 28, 2019

Move over (if you can) & slow down when you see flashing lights. Troopers and local law enforcement are out at crashes and vehicle spin outs. No travel advised in the metro. #mnwx pic.twitter.com/3KXWbDE129 — MN State Patrol (@MnDPS_MSP) December 28, 2019

Unless you want to be stuck at a standstill like this one on the Mendota Bridge, stay home! Roads in the metro and surrounding areas are covered in ice and travel is dangerous. Stay in your vehicle and keep your seat belt on if you are in this situation. #mnwx pic.twitter.com/LcuBZu54UH — MN State Patrol (@MnDPS_MSP) December 28, 2019

We’ve seen plenty of vehicles in ditches today. This one is on Highway 36 in Little Canada.@KSTP pic.twitter.com/jN6Z0guWr4 — Callan Gray (@CallanGrayNews) December 28, 2019

Temperatures were starting to warm up in the Twin Cities by Saturday afternoon.

Cleanup ongoing of just one of MANY accidents around the metro area this morning. Don't travel for a few hours unless you have no choice. pic.twitter.com/qlnrahz4yJ — NWS Twin Cities (@NWSTwinCities) December 28, 2019

In Denver, the blowing and drifting snow continues to cause limited visibility for drivers, which could wreak havoc on roadways.

FAA has a Traffic Management Program for @DENAirport. Delays averaging 50 minutes. 73 cancelled flights so far this morning. #cowx pic.twitter.com/aP5ANhNuuX — April Schildmeyer (@Aschildmeyer) December 28, 2019

TRAFFIC ALERT: new crash NB I-25 approaching Hampden Ave. Two left lanes blocked pic.twitter.com/d0nmAboOi1 — April Schildmeyer (@Aschildmeyer) December 28, 2019

(MORE: What every motorist needs to know about driving in snow)

By Sunday morning, heavy snow and strong winds will be hitting much of North Dakota, South Dakota, Nebraska and northern Minnesota. Some areas could get more than a foot of snow.

Now we look at US 12 near Ipswich. Conditions aren’t getting better. Consider taking a snow day! #keepSDsafe https://t.co/73oT5qhPLS pic.twitter.com/2it2TRGwvl — SD Highway Patrol (@SDHighwayPatrol) December 28, 2019

Conditions will be rainy and milder in Minneapolis, the Great Lakes and Chicago.

Airlines have issued weather waivers for passengers traveling through the Midwest and upper Midwest airports Saturday and Sunday.

By Sunday night, snow and icy conditions will persist in the upper Midwest with areas of heavy rain, thunderstorms and possible flash flooding in the South.

By that point the storm will be taking aim on the Northeast, bringing rain and a wintry mix.

By the Monday morning commute, rain will be falling across much of the Northeast with heavy downpours possible in some spots.

Freezing rain will be a concern from upstate New York into parts of New England.

But this storm is forecast to clear out Tuesday morning in time for New Year's Eve.

ABC News' Mina Kaji contributed to this report.