Thanksgiving travel is underway and record numbers of Americans are taking planes, trains and automobiles to reach their holiday destinations, creating travel chaos across the country.

Video shows major traffic jams are already forming on the road as commuters sat in bumper-to-bumper traffic on the 405 Freeway in Los Angeles Tuesday night.

AAA projects 55.4 million people will travel at least 50 miles from their home over the holiday. They estimate 49.13 million of them will travel by car and 4.69 million will fly.

According to FlightAware, as of Wednesday morning 1,240 flights within, into, or out of the United States have been delayed and 48 have been cancelled. 

In the nation’s capital, video shows massive lines forming at Reagan National Airport early in the morning Wednesday.

LOS ANGELES: A major traffic jam formed on the 405 Freeway in Los Angeles Tuesday night

REAGAN AIRPORT: Wednesday morning massive lines formed at Washington, D.C.’s Reagan National Airport

WASHINGTON, D.C.: Heavy traffic moves along Interstate 295 on Wednesday morning

PHILADELPHIA: Travelers wait in line to board an Amtrak train at 30th Street Station in Philadelphia on Wednesday

As 55.4 million Americans are expected to travel this Thanksgiving holiday, here is what travelers need to know:

• Drivers in Los Angeles sat in bumper-to-bumper traffic on the 405 Freeway Tuesday night. Wednesday from 2 p.m. – 6 p.m. will be the worst time to drive
• D.C.’s Reagan Airport saw massive lines Wednesday morning. It’s advised to come early, airport security lines are moving at a rate of 15-30 minutes
• At least 1,000 flights within, into, or out of the U.S. have been delayed, 45 have been cancelled
• Major rain and snow storms are forecast across the country Wednesday that could cause travel delays 

The National Weather Service forecasts major rain and snow storms across the country Wednesday that could disrupt travel. 

Widespread rain is forecasted across the East Coast and parts across northern New England, particularly Maine, are expected to see snowfall.

The northern and central Rockies are predicted to have a white Thanksgiving this year due to a blast of artic air.

The Federal Aviation Administration (FAA) said that low clouds and wind could impact flights at Boston, New York, Philadelphia, Washington D.C., Charlotte and Seattle airports on Wednesday.

Photos out of John F. Kennedy International Airport Wednesday morning show crowds of people flocking to the airport to fly to their Turkey Day destinations.

Video shows enormous lines in the Pittsburgh International Airport. WTOV9 reporter Addison Albert said the TSA PreCheck line is reaching past the rope.

AAA projection of 55.4 million travelers is up 2.3 percent over the last year and the third highest since the group began tracking holiday travel in 2000. 

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The busiest days to fly will be Tuesday and Wednesday as well as the Sunday after Thanksgiving.

The Transportation Security Administration expects to screen 2.7 million passengers on Wednesday.

Sunday will draw the largest crowds with an estimated 2.9 million passengers, which would narrowly eclipse a record set on June 30.

REAGAN AIRPORT: Travelers wait in long lines to go through Transportation Security Administration security screening

JFK AIRPORT: People line up at John F. Kennedy International Airport in New York the Wednesday before Thanksgiving

JFK AIRPORT: The Transportation Security Administration expects to screen 2.7 million passengers on Wednesday

JFK AIRPORT: AAA projects 4.69 million Americans will fly over the Thanksgiving holiday

The silver lining for travelers by plane and car alike is that prices are tumbling down. Airfares are averaging $268 per ticket, down 14 percent from a year ago, according to the travel site Hopper.

Gasoline prices are down about 45 cents a gallon from this time last year. The national average was $3.30 per gallon on Monday, according to AAA, down from $3.67 a year ago.

A survey of GasBuddy users found that despite cheaper pump prices, the number of people planning to take a long driving trip this Thanksgiving hasn´t changed much from last year.

FAA Administrator Mike Whitaker urged travelers to ‘be nice to flight crews’ who are ‘working around the clock to make sure passengers get to their destinations safely’.

He warned the FAA has ‘zero tolerance for unruly behavior’ in the public appeal on X, formerly known as Twitter.

US Transportation Secretary Pete Buttigieg said during a news conference Monday that the government has tried to better prepare for holiday travel over the last year.

He said measures like hiring more air traffic controllers, opening new air routes along the East Coast and providing grants to airports for snowplows and deicing equipment had been put in place.

But he warned travelers to check road conditions and flight times before leaving home. ‘Mother Nature, of course, is the X factor in all of this,’ he said.