Winter Storm Boreas,already blamed for at least fourteen deaths, is a massive storm that will impact the nation from coast to coast with rain, snow, sleet, and ice during the busiest travel week of the year. It's bringing a mix of snow, sleet and freezing rain to parts of Arkansas, Oklahoma and Texas on Monday then will trudge east this Thanksgiving week.

"Before this is over, Winter Storm Boreas will have impacted 100 million people," said The Weather Channel's winter weather expert Tom Niziol.

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Nearly 300 American Airlines and American Eagle flights were canceled in and out of Dallas-Fort Worth International Airport on Monday due to the weather, spokeswoman Laura Masvidal said, mirroring disruptions at the air hub a day earlier. Some of the country's busiest airports - New York, Washington D.C., Philadelphia, Boston and Charlotte, N.C. - could see big delays.

On Monday, the storm brought a mix of snow, sleet and freezing rain to parts of Arkansas, Oklahoma, Missouri, southern Kansas and Texas.Meteorologists say they expect the Arctic mass to head south and east and threaten plans for Tuesday and Wednesday as people hit the roads and airports for some of the busiest travel days of the year.

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"When we get into mid-week, as this system combines with cold air in the Northeast, it will produce a lot of rain along I-95," said Niziol. "From Western Penn. to Rochester, N.Y. as much as 8 to 12 inches of snow could fall."

Dangerous Driving

As of Monday night, Boreas was blamed for at least 14 total deaths in five states. Most of the fatalities were tied to traffic accidents.

Five people were killed on Texas roads during the weekend. In Oklahoma, the Department of Public Safety says four people died as a result of weather-related accidents.

Before moving into the Plains, the system hurled high winds, snow and flooding rains into the West and Southwest.New Mexico State Police say a 4-year-old girl was killed in Roosevelt County Friday when her family's car slid off the road and overturned.Friday, firefighters in Tucson recovered the body of a man who was thought to be swept away by high water in the Santa Cruz River.

The system was also blamed for three wind-related deaths in California late last week.

Holiday Travelers Concerned

Jeff Smidt is traveling Wednesday from his home in Toronto to visit his family in Andover, Mass., just outside Boston.

"My understanding is that I'm traveling at like the worst time ever," he said.

Smidt tried to get on an earlier flight but JetBlue told him it isn't waiving any change fees yet.

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"I'm just hoping I also don't become a statistic during the holiday weekend," he said. "Worst comes to worst, it will be an eight-hour trek down Interstate 90."

Ninety percent of travelers this week will drive, according to AAA, and an estimated 38.9 million people - 1.6 percent fewer than last year - are expected to drive 50 miles or more from their home.

Gas is about 15 cents cheaper than last year, AAA said Monday, with a gallon of regular selling for $3.28.

MORE ON WEATHER.COM: Winter Storm Boreas Photos

Traffic on I-35 at the 33rd street bridge in Edmond Sunday, Nov. 24, 2013. (Doug Hoke/The Oklahoman)