By Mackenzie Tatananni

Tens of millions of Americans hitting the road and skies for the nation's 250th birthday are facing a chaotic travel weekend driven by a combination of severe weather and major event security.

A busy travel period kicked off last Saturday, June 27, with the American Automobile Association (AAA) projecting 72.2 million people will travel more than 50 miles from home through July 5. Of those, 61.4 million were expected to drive.

The national average price for a gallon of gas stood at $3.82 on Thursday, according to AAA data — down 56 cents from a month ago, but still higher than prices over the past three years, the group said.

Although gas prices are doing little to deter travelers, unavoidable disruptions lie ahead for many air and rail passengers. Delta Air Lines has warned travelers in the Northeast to expect delays, citing airspace restrictions tied to the America 250 celebrations.

The festivities at the National Mall on July 4 will include military flyovers, near-continuous air shows, and an evening fireworks display preceded by remarks from President Donald Trump, who vowed to appear despite the sweltering heat. The celebrations are funded by a mix of taxpayer dollars and donations from corporate sponsors, including Palantir Technologies and Lockheed Martin.

Affected airports include Hartsfield-Jackson Atlanta International, Delta's primary hub and historically the nation's busiest. But the heaviest disruptions will impact flights in and around the nation's capital, namely Ronald Reagan Washington National.

The Metropolitan Washington Airports Authority is restricting all inbound and outbound flights starting at noon on Saturday, citing the American 250 celebration. Regan terminals will operate at a "reduced capacity" until reopening at midnight on July 5, the agency said.

United Airlines has flagged Newark Liberty International Airport and LaGuardia Airport as two other hubs facing delays due to the America 250 celebrations. The carrier is offering to waive change fees and fare differences for travelers who alter their plans as a result of the disruptions, subject to certain conditions.

Weather is also factoring into travel delays, as powerful winds and rain swept across the Midwest on Friday, downing trees and sparking power outages. Chicago O'Hare International Airport was suffering the worst disruptions of any major U.S. airport on Saturday, with 7% of all arrivals and 8% of departures delayed, according to FlightAware data.

This has an outsized impact on United, seeing as Chicago O'Hare handles a large share of the airline's daily flights and passenger transfers. Over the past 24 hours, 620 flights have been canceled, including 118 today alone. The disturbances peaked on Friday, when severe storms triggered ground stops.

Rail travelers face similar issues. Amtrak issued an advisory through Saturday for passengers in the Northeast, Southeast, and Midwest, cautioning that "forecasted extreme temperatures" may force trains to run at reduced speeds.

Write to Mackenzie Tatananni at mackenzie.tatananni@barrons.com

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