The Beltway near Tysons Corner, Va. (Michael S. Williamson/The Washington Post)

Expect heavier traffic on the region’s highways this weekend as more Washington-area residents plan to kick off the summer season with a road trip.

About a million area residents will venture at least 50 miles from home this Memorial Day weekend, the highest number in 12 years, according to forecasts. Nine in 10 travelers will get to their destination by car, bringing heavier traffic to the region’s road network starting Thursday afternoon.

Nationwide, more than 39 million Americans are expected to travel away from home over the long weekend.

The expected spike in travel mirrors positive growth in the U.S. travel industry this year, said Tom Calcagni, regional director of public and government affairs for AAA Mid-Atlantic. It also comes as more people are driving overall, lured in part by lower gas prices.

“Higher confidence has led to more consumer spending, and many Americans are choosing to allocate their extra money on travel this Memorial Day,” Calcagni said.

Cars remain the preferred mode of travel. Nationwide, AAA estimates that nearly 35 million people will get to their destinations by car, an increase of about 2.4 percent over last year. The remaining travelers will fly or take other modes of transportation, including train and bus.

In the Washington area, the majority — 891,500 — of those traveling say they plan to drive. More than 78,200 are expected to fly, and 29,100 will go by bus, train or boat, AAA said.

With so many people expected to drive to their destinations, transportation officials and experts say planning is key, including adding plenty of time and patience to your trip.

“This is the beginning of crab season, but don’t be crabby. Don’t get hot, be cool,” said Jim Ports, deputy secretary of operations at the Maryland Department of Transportation.

“Enjoy your family time in the vehicle. Turn up the music. Relax,” he said. “It’s not important how fast you get there. The most important thing is that you get there safely.”

Air travel also is expected to be the highest in years for the holiday, both locally and across the United States, a sign that recent high-profile airline-related incidents captured on video are not discouraging Americans from flying. Locally, travelers should anticipate longer lines at the region’s three airports — Reagan National, Dulles International and Baltimore-Washington International Marshall — where air travel is expected to be more than 6 percent higher this holiday weekend than last year.

The incidents include mayhem that erupted at Florida’s Fort Lauderdale airport earlier this month when angry passengers clashed with Spirit Airlines employees and law enforcement after the airline canceled several flights. Last month, police violently dragged a passenger off a United Airlines flight, igniting outage among consumers and officials and leading some airlines to change their policies affecting bumped passengers.

If you’re planning to fly this weekend — or anytime this summer — airport officials say you should arrive at least two hours before a domestic flight and three hours before an international flight. Make sure to check the status of your flight before heading to the airport.

You can check online at the Transportation Security Administration website (tsa.gov) to see what security wait times are like and plan accordingly. The website ifly.com also lets you check wait times, delays and a variety of information for any airport.

Peak travel times at the Washington area’s airports are during the early morning — from 5:30 to 8 a.m. — and late afternoon — from 3:30 to 5:30 p.m. Parking facilities at National tend to fill quickly during holiday weekends, so reserve a spot in advance or try an alternative such as Metro or ride hailing.

Gas prices are the highest they’ve been for the holiday since 2015 but are still more than a dollar below what they were five years ago, when the average price in the United States was $3.64 per gallon.

The national average price for a gallon of gas this week as of Wednesday was $2.36, 8 cents more than last year. The average price in the Washington area was $2.34 a gallon, 6 cents more than 2016, AAA said.

To help speed you along your way, transportation agencies in Virginia and Maryland are suspending major road work during the holiday weekend and lifting lane closures where possible. Still, officials are asking drivers to be extra vigilant in work zones where there are new traffic patterns.

Based on historical traffic data, holiday travelers are likely to see the heaviest congestion between 11 a.m. and 7 p.m. Friday and Monday. Data shows that traffic for the holiday period will also be heavy Thursday afternoon.

In Virginia, holiday traffic congestion is generally heavy on Interstate 95 southbound and Interstate 64 eastbound Saturday morning through afternoon as scores of people head to the coast. Traffic is heavier on I-95 northbound and I-64 westbound Monday from noon through late evening. HOV restrictions on Interstates 66 and 395 will be lifted on Memorial Day.

In Maryland, beachgoers should expect to hit backups on the Chesapeake Bay Bridge. The best times to travel are before 10 a.m. and after 10 p.m. Thursday, Friday, Sunday and Monday. Expect heavy traffic between 7 a.m. and 5 p.m. Saturday. This weekend, travel on Route 50 may be particularly challenging as thousands of people visit Annapolis for commencement ceremonies at the U.S. Naval Academy.

Although this is a big getaway weekend, the District is also a major attraction for vacationers, and many travelers will be going to Memorial Day weekend events in and around the nation’s capital.

“With gas prices down, more people hit the roads in the vehicle,” Ports said. “We do know that this is going to be a much busier holiday weekend.”