Long lines were already formed early Friday morning at San Jose’s Norman Y. Mineta International Airport ahead of the Independence Day on Wednesday.
The Transportation Security Administration says it's expecting to screen 2.6 million passengers at U.S. airports Friday, more than the usual average 2.2 million travelers.
Gabbi Taylor arrived at SJC before 4 a.m., when the terminals opened, for the first 6 a.m. flight to go to a family reunion, she told NBC Bay Area.
Another traveler, Jeffrey Taylor, says "TSA usually gets pretty backed up so you gotta get here early. You have a lot of first time travelers with kids who just don't know the rule."
The TSA recommends people to arrive at the airport at least 90 minutes before their flight.
Officials at San Francisco International Airport said they expect around 100,000 passengers to depart SFO on Friday, making it the busiest day of the year for the airport.
"Airlines, TSA, and SFO are planning additional staffing to match the activity," an airport spokesperson said.
Passengers should also be aware of the new TSA rules on powder limitations for international flights. Passengers carrying powders in containers larger than a soda can will be checked for its content.
The rule is already in effect for domestic flights.