AAA forecasts 43 million Americans will hit the roads over the holiday -- 5% more than the volume the organization saw in 2019.
"What's interesting is compared to 2019 travel, volume by car is actually up," Jeanette McGee, director of AAA's external communications told ABC News. "It just proves that the road trip is back stronger than ever."
McGee said major metropolitan areas like Atlanta, Boston and San Francisco will see traffic three to five times higher than a typical day. McGee said drivers should avoid traveling at peak times.
"If you're headed out for the holiday weekend, you're going to want to avoid traveling between 3 and 6 p.m. on Thursday and Friday," McGee said. "You're going to have commuters mixing with people getting out of town. So, the best day to travel is going to be Sunday, and if you're returning on Monday, definitely do so earlier in the day."
Before hitting the road, be prepared for high prices at the gas pump -- according to AAA, prices will be the highest since the same period in 2014.
"Gas prices are expensive, and they are not letting up," McGee said. "The national average is $3.09 and we expect it to increase ahead of the holiday weekend."
Rental car prices are also expected to be high, with the global microchip shortage still affecting vehicle supply.
"Rental cars are definitely expensive this summer, and it's really important that if you're planning a trip that you reserve early," McGee said.
According to Hopper, an online travel booking tool, rental car prices are up 100% relative to where they were at the beginning of the year.
"They were about $50 in January and they're about $110 each day, currently," Hopper economist Adit Damodarn told ABC News. "We thought that those prices would start to slow down, but the catalyst for kind of bringing those prices back down would be increasing the supply of rental cars."
While air travel is not expected to exceed 2019 numbers, experts said airlines will carry the most passengers since the start of the pandemic.
Domestic destinations like Las Vegas, Miami and Orlando are the most popular, according to Hopper. The Caribbean and Mexico are the most popular international destinations, according to Damodarn.
"July 4 is the most searched weekend of summer 2021 thus far," Damodarn said. "It's going to be the busiest travel weekend since the start of the pandemic."
American Airlines expects to operate nearly 5,500 daily flights from Thursday to Monday, with the busiest travel days being Thursday and Friday, a spokesperson said.
United Airlines expects to fly 2 million customers from Thursday to Tuesday, with Thursday and Monday anticipated to be its busiest days.