
Blizzards are battering the U.S. from coast to coast, triggering devastating flight cancellations and delays on the biggest travel holiday of the year - as 50 million people across the country are placed under a winter weather alert.

Two winter storms swirling over the country have already claimed three lives. Two children were found dead and another was missing in Arizona on Saturday after a car they were in got stuck while crossing a storm-swollen creek outside Phoenix.

A 37-year-old man was killed in a car accident near Cavour, South Dakota early Friday morning after the pickup truck he was in lost control on the icy road, fell into a ditch and rolled over.

This week snow, icy, freezing rain and gust winds are forecast to blow the West Coast and the Northeast, hitting Chicago, Philadelphia, Boston and New York hard.

The National Weather Service warned that Sunday's forecast will bring heavy mountain snow and rain in California, and heavy snow and blizzard conditions from the Upper Midwest to the Northeast. In the Midwest the powerful storm will bring damaging winds and large hail. A tornado watch is in affect for parts of Texas, Louisiana, and Arkansas.

So far the storms have cancelled over 600 flights within, into, or out of the U.S. and over 4,000 were delayed as of Sunday afternoon, during the busiest travel holiday of the year.

Playing in a winter wonderland! Flurries came down in East Rutherford, New Jersey for Sunday's football game between the New York Giants and the Green Bay Packers

Workers pictured clearing the line markers in the snow during Sunday's NFL game at the MetLife Stadium in New Jersey

Three people have died in dangerous winter storms battering the U.S. during the post-Thanksgiving weekend, as 50 million people across the country are under winter weather alert. Massive snowfall pictured about in Fort Tejon, California

The South Dakota Highway Patrol shared this picture showing Highway 14A between Sturgis and Deadwood completely covered in Snow in the Black Hills area, urging locals to 'Please stay home, don't risk it'

Blizzard conditions were reported at Lake Superior in Minnesota as an inch of snow fell per hour on Saturday evening

A tractor truck carrying cattle rolled over onto its side while driving in the dangerously icy roads In Buffalo County, South Dakota on Saturday. The driver was unharmed in the incident. 45 of the 47 cows on board survived

The National Weather Service shared this snowfall forecast map revealing heavy snowfall will impact Western states, the Upper Midwest and the Northeast, with some areas seeing between four to six inches of snow, through Wednesday

This map shows the snow forecast in the Northeast, hitting New York through Maine hard with five to 12 inches of snow

This year AAA estimated nearly 55million people traveled via roads, rails, and plane for holiday travel from Wednesday to Sunday, meaning the wintry weather will abrupt the travel plans for millions of people.

The storm hitting the Northeast has been named Winter Storm Ezekiel by the Weather Channel and is forecast to bring up to a foot of snow, according to NWS.

New York is expected to see two inches of snowfall each hour on Sunday and Monday. Freezing rain, sleet and snow drizzled over Pennsylvania, New Jersey and New York on Sunday.

A whopping 48 inches of snowfall was recorded Sunday evening in California and Utah at the Big Bear Resort and Snowbasin Resort up in the mountains, respectively.

On Sunday 20 inches of snowfall was recorded in Gary New Duluth, Minnesota

To brace for the storm New York Gov. Andrew Cuomo placed the National Guard on standby and the state's emergency operations center on 'enhanced monitoring mode'.

Massachusetts also issued an 'awareness statement' warning 8 to 12 inches of snow over the state interior and up to a whopping 17 inches near the Berkshires.

The heaviest snow is forecast to hit the western Catskills reaching about two feet. New York City and Long Island are forecast to receive one to four inches. The area around Albany could see 12 to 18 inches.

'The amount of the population under a warning, advisory or watch is extensive — it’s in the millions,' Meteorologist Brian Hurley at the National Weather Service’s Weather Prediction Center said to the Washington Post.

The children who died in devastating floods in Arizona were first reported missing late Friday after a vehicle got stuck in Tonto Creek near Tonto Basin, northeast of Phoenix, the Gila County Sheriff's Office said in a statement.

Rescue workers in helicopters successfully reached four other children and an adult who were stranded on an island in the creek and a second adult who was on the shore. A search was launched for the three missing children.

Two of those children, a boy and a girl, both about five-years-old, were found dead on Saturday about three miles downstream from where the vehicle became submerged, said Virgil Dodd, a sheriff spokesman.

About 30 first responders were still searching for the missing girl. 'We hope we find the last one and bring her to safety,' Dodd said.

The two adults were parents of four of the seven children involved in the incident. Dodd said the group was believed to be from out of town, but no details were known.

The group was in the area for a family reunion during the Thanksgiving holiday, the KPNX news channel reported.

Airlines for America, the airline industry's trade group, expects 31.6 million passengers during what could be the busiest day ever recorded for American air travel on Sunday. The map above shows the impact to travel across the US

This map shows Sunday evening's forecast for freezing rain and snowfall which extends from the Midwest to the Northeast

This weather map shows the impact of a major winter storm moving east on Sunday bringing heavy snowfall through Tuesday night. In the West, heavy snow, gusty winds and rain will hit California, Washington, Oregon, and Idaho

Top snow totals as of Sunday California: 48 inches - Big Bear Resort Utah: 48 inches - Snowbasin Resort Arizona: 30 inches - Arizona Snowbowl South Dakota: 30 inches - Lead Wyoming: 30 inches - Muddy Gap Wisconsin: 26 inches near Cornucopia Idaho: 20 inches - Sun Valley Resort Source: Weather.com Advertisement

The city of Tusayan in Arizona declared a state of emergency due to nearly two feet of snow and lack of electricity on Friday. Tusayan is located near the Grand Canyon National Park where over a foot of powdery snow was measured as of Sunday.

More than 1,000 people were left with no heat of power since early Friday, leading a shelter to be set up in the Grand Canyon National Park in Arizona.

'We are working to arrange emergency shelter at the National Park, in buses, and at other locations,' Mayor Craig Sanderson said in a written statement. 'We are working with the County Emergency Management team, Arizona Department of Transportation, (Arizona Public Service) and the National Park Service with a priority on clearing roads.'

California saw similar outages amid intense wind and rain. In parts of Southern California were left in the dark, according to Southern California Edison due to storm related issues such as strong winds and snow topped trees downing wires. The company said it would pass out firewood to affected residents.

The bodies of two children were found Saturday after a truck they were in was swept away while attempting to cross a runoff-swollen creek in the Tonto National Forest in Arizona. About 30 first responders were still searching for a missing girl

The Gila County Sheriff's Office said helicopters on Friday rescued two adults and two children who also were in the military-style truck swept downstream in Tonto Creek near the small community of Tonto Basin

A cross at the site where three children were swept away in flooding on Tonto Creek at Tonto Basin in Arizona

Blizzard conditions created a white out in North Lake Tahoe in California, leading authorities to warn locals to stay indoors

Arizona also saw extreme snow and rain, leading to the death of two young children on Satuday

The map above shows the forecast nationwide from Sunday morning 7am EST through Monday morning 7am EST

The map above shows the forecast nationwide from Monday morning 7am EST through Tuesday morning 7am EST

While blizzards and deep snowfalls are anticipated for much of the Midwest and the Northeast, heavy snow has already wrecked havoc in some states including South Dakota and Colorado.

People were advised not to travel in western South Dakota and a Festival of Lights Parade scheduled for Saturday had to be cancelled in rapid City due to high winds.

The airport in rapid City, South Dakota also closed Saturday after visibility dropped so low crews couldn't plow roadways or use their equipment, according to Weather.com.

Blizzard conditions also hit Minnesota, where two lanes of the I-94 highway near Moorhead was forced closed on Saturday following a multi-vehicle accident involving at least one semitrailer.

A No Travel advisory was issued in Duluth as the NWS reported snow falling at a rate of 1 inch per hour and winds gusting about 50mph.

The National Weather Service said the storm is expected to drop six to 12 inches of snow from the northern Plains states into Minnesota, Wisconsin and Upper Michigan. High winds and ice are expected to make travel almost impossible in some places.

Forecasters warn that people traveling throughout the weekend should be aware of the storm's effects, with officials in states including Arizona urging travelers to wait out the weather before attempting to travel.

A woman and a child cross the street while battling the weather on a windy and snowy morning in Greeley, Colorado on Saturday. The weather therre caused the city to cancel its annual Greeley Lights the Night parade

A driver of a pickup truck hits high water while traveling in Owensboro, Kentucky, after heavy rain in the area on Saturday

Powdery white snow took over the Mammoth Mountain Ski Area in Mammoth Mountain, California

A traveler makes his way to a shuttle stop after a pre-Thanksgiving holiday snowstorm caused more than 460 flight cancellations at Denver International Airport, Colorado on Tuesday

More than a foot of fresh snow and strong wind gusts are expected to combine to create ground blizzard conditions along the Rocky Mountain Front in northern Montana.

The National Weather Service says the blizzard warning begins at 9 p.m. Saturday and runs through Tuesday morning in areas including Browning and Heart Butte on the Blackfeet Indian Reservation.

Meteorologist Christian Cassel told the Great Falls Tribune people could be stuck in their homes for at least a day due to the near zero visibility.

The Glacier County Sheriff's Office posted the warning on its Facebook page noting the possible 60 mph wind gusts. It advises residents to stock up on groceries and firewood and 'maybe a backlog of new memes you haven't read yet.'

It closes with an emphatic request to stay off the roads during the blizzard.

A powerful storm making its way east from California across the U.S. is causing travel chaos for millions of people returning home after Thanksgiving. Parked cars are seen covered in snow on Saturday in Denver, Colorado

A worker piles snow in a parking lot in west Denver, Colorado on Saturday. Some areas near Denver received over two feet of snow over the Thanksgiving holiday

A driver tries to dig his car out of heavy snow in foothills west of Denver, Colorado Saturday

Adding to the weather woes is a powerful Nor'easter storm that is developing off the East Coast which could combine with the cold air blowing in from the West and cause the first heavy snow of the year.

The National Weather Service said in its latest forecast: 'Freezing rain will be the initial threat for portions of Pennsylvania and New York, as well as the Central Appalachians, with ice accumulations over a tenth of an inch possible in some areas.

'Snowfall amounts in the Northeast are currently forecast to be 4 to 8 inches from parts of New York, southern Vermont and New Hampshire, and Massachusetts through Sunday night, with more expected on Monday.'

A nor'easter gets its name for the direction of strong winds and Arctic air which blows in from the Atlantic Ocean.

Heavy snow continues to batter parts of of the Northern and Central Rockies, as blizzard warnings are in effect for eastern Wyoming into western South Dakota and northern Nebraska.

Winter Storm Warnings are in place in Utah and Colorado, and extending eastward across the northern Rocky Mountains, northern Plains and Upper Midwest states.

Winter Weather Advisories are in effect across the lower elevations of the central and northern Rockies, southeastern South Dakota to central Michigan, and portions of Pennsylvania and New York.

Winter Storm Watches are in effect for parts of Michigan and the Northeast into the northern Mid-Atlantic region.

In the South, heavy rain and thunderstorms are forecast in parts of the Tennessee and Ohio Valleys.

The Weather Channel says alerts will still be in place for the North Sunday and will last in the Northeast until Tuesday morning

The National Weather Service said in its latest forecast: 'Freezing rain will be the initial threat for portions of Pennsylvania and New York, as well as the Central Appalachians, with ice accumulations over a tenth of an inch possible in some areas. Snowfall amounts in the Northeast are currently forecast to be 4 to 8 inches from parts of New York, southern Vermont and New Hampshire, and Massachusetts through Sunday night, with more expected on Monday'

Winter Weather Advisories are in effect across the lower elevations of the central and northern Rockies, southeastern South Dakota to central Michigan, and portions of Pennsylvania and New York

The weather could cause problems for millions of passengers heading home after the Thanksgiving break on Sunday.

Airlines for America, the airline industry's trade group, expects 31.6 million passengers during what could be the busiest day ever recorded for American air travel.

A record 31.6million passengers were forecast to travel on US airlines during the Thanksgiving holiday period as a hole - a 3.7% rise from last year.

As of Sunday morning there were over 2,000 delays within, into or out of the U.S. and over 500 cancellations.

Travel impacts are expected to last through Monday.

Delta Airlines already announced weather waivers for 16 cities in the Upper Midwest on Saturday and 22 cities in the Northeast for Sunday and Monday, including New York and Boston Airport.

American Airlines issued waivers for travelers on Sunday and Monday flights to and from John F. Kennedy and LaGuardia airports in New York as well as airports in Boston, Buffalo, Pittsburgh, and Toronto, Canada.

Snow plow works at snow removal off Interstate Highway 70 in the foothills west of Denver, Colorado on Saturday

New York City could be hit with up to eight inches of snow on Sunday as powerful storm approaches from the west The first winter storm of the season could dump between four to eight inches of snow as a powerful storm from the West makes its presence felt, according to the National Weather Service. Freezing rain will be the initial threat for Pennsylvania and New York, as well as the Central Appalachians, with ice accumulations over a tenth of an inch possible in some areas. Snowfall amounts in the Northeast are currently forecast to be four to to eight inches from parts of New York, southern Vermont and New Hampshire, and Massachusetts through Sunday night. 'There might be a small accumulation before it changes over to mostly rain later Sunday,' Accuweather meteorologist Tom Kines told The New York Post. The New York Department of Sanitation has issued a snow alert starting at 3 am Sunday. The DSNY will coordinate with New York City Emergency Management and the Department of Transportation on snow clearing protocol. The National Weather Service warned that travel could be disrupted on Sunday, particularly with millions of people on the move as they return home following the Thanksgiving break. Conditions could be difficult for commuters on Monday morning, with freezing rain or snow falling as children go to school and people head back to work. Advertisement

Back-to-back snowstorms and strong winds combined to complicate travel across much of Wyoming, where roads were closed in the eastern and southern parts of the state because of whiteout conditions.

The National Weather Service reported four inches of snow fell in Cheyenne from 7 p.m. Friday through 10 a.m. Saturday and 'has been blown all over kingdom come by our winds,' said meteorologist Andrew Lyons.

That was added to a foot of snow that fell before Thanksgiving.

Wind gusts up to 50 mph created ground blizzards and below-zero wind chill temperatures in some areas. A 77 mph wind gust was reported in the mountains between Cheyenne and Laramie.

Roads in and out of Casper and Cheyenne were closed Saturday afternoon, including the entire 300-mile stretch of Interstate 25 in Wyoming. Interstate 80 across southern Wyoming also was closed.