Airports, highways, beaches and theme parks are expected to be packed across the U.S. this Labor Day weekend as a lot Americans mark the unofficial end of summer the same way they celebrated the season’s unofficial start: by traveling.

After what’s already been a record-breaking summer for air travel, the Transportation Security Administration predicted its agents would screen more than 17 million people during a holiday period that started Thursday and runs through next Wednesday, about 8% more than last year.

The TSA anticipates Friday to be the busiest day. In a sign the summer travel season really is winding down, however, the agency said that fewer than 2 million passengers passed through airport security checkpoints one day this week — the first time that has happened since early March.

If you plan to be part of the crowds heading out of town to enjoy one last blast of summer, here is a rundown of what you need to know.

How is holiday travel going so far?

Busy, as expected. TSA screened 2.75 million travelers at the nation’s airports on Thursday, nearly 130,000 more people than it screened on the same day last year.

Airlines canceled more than 500 U.S. flights Thursday, with nearly 300 of those at Dulles and Reagan National airports near Washington, D.C.

Since June 1, airlines have canceled 1.8% of all U.S. flights and another 25% have been delayed — identical to the rates last summer — according to figures from FlightAware.

Where are the potential trouble spots?

Weather is the leading cause of flight delays. Forecasts call for rain and maybe scattered thunderstorms from Texas to New England plus parts of Florida over the weekend, and showering more of the Southeast on Monday.

Seattle-Tacoma International Airport was still working to restore all services after what airport officials described as a possible cyberattack last weekend. Flights have been running normally all week, but airport told passengers to arrive extra early for flights and to avoid checking bags, especially if they are on a smaller airline, because of problems with the bag-sorting system.

What are prices like?

Motorists are getting a break on gasoline. The nationwide average Friday was $3.35 per gallon, compared to $3.83 a year ago, according to AAA.

For electric vehicles, the average price for a kilowatt of power at an L2 commercial charging station is about 34 cents. The average is under 25 cents in Kansas and Missouri but tops 40 cents in several states, including New Hampshire, Tennessee and Kentucky. Hawaii is the costliest, at 56 cents.

Average airfares in July were down 7.1% from June and 2.8% from July 2023, according to the government’s consumer price index. The trend appeared to be accelerating as the peak summer-vacation season comes to an end.

“Now we’re falling into that traditional fall season when demand slumps, and you’re also seeing that in airfares,” said Steve Hafner, CEO of the travel metasearch site Kayak. “Airfares are down from the summer about 26% already, and they’re down even from the previous fall, about 4%.”

When is the best time to hit the road?

Transportation-data provider INRIX says the worst time to travel by car on Friday will be between 2 p.m. and 6 p.m. That flips on Saturday, when you’ll want to avoid driving between 8 a.m. and 11 a.m.

For the return trip, pretty much all day Monday — from 11 a.m. to 8 p.m. — will be a slog, according to INRIX.

And watch out for risky drivers. New data from Arity, part of insurance giant Allstate, indicates that speeding over 80 mph is up 83% and “very high speeding” — faster than 100 mph — is up more than 50%.

In a surprising twist, however, Arity says distracted driving has dropped on the last three Labor Days.

When will airports be busiest?

The TSA expects to screen 2.86 million people Friday. That’s an impressive number, but it still won’t rank in the top 15 days in TSA’s history — 14 of which have come this year. The single-day record of 3.01 million was set on July 7, the Sunday after Independence Day.

TSA says it has enough screeners to keep the time it takes to get through regular lines to 30 minutes or less and to no more than 10 minutes for PreCheck lines.

American Airlines expects to operate 6,400 flights Friday, the same as Thursday, and 6,300 on Labor Day itself.

What should I do if my flight is delayed or canceled?

First, check your itinerary before leaving for the airport. It’s better to be stuck at home than stranded at the airport.

If your flight is canceled, the airline might automatically rebook you. That might not be the best option.

“Get on the phone (to the airline’s help center), get in front of an agent, reach out to the airline via social media if you have to, but find out what the other options are,” says Julian Kheel, the founder and CEO of Points Path, a browser extension that lets users compare fares with deals available using frequent-flyer points. “You can almost always find another option that may work better than the one offered by the airline.”

Kheel said agents at the airport have more leeway to help, but they might be inundated if there are many canceled flights. DIY rebooking on the airline website or app might be faster, he said.

Phone tip: Some experts say if the airline has international help numbers, call one of those to get through more quickly than on the U.S. line.

What about refunds and reimbursement?

Airlines are required to provide refunds — including for extra fees paid — to passengers whose flights are canceled for any reason. However, they are not required to pay cash compensation, and no major U.S. airlines do. Only Alaska, Southwest and JetBlue even promise travel vouchers if the cancellation is their fault.

If you’re stuck overnight, ask the airline about covering the costs of a hotel, meals and ground transportation. All major U.S. airlines except Frontier promise to help with all three for “controllable” disruptions, according to the Transportation Department’s airline-policy dashboard. However, those commitments don’t apply to cancellations caused by weather.

Keep receipts for all out-of-pocket expenses in case you can file a claim later.

A few final tips

— Leave early. Everything will take longer than you expect, including getting through airport security. If you plan to park at the airport, make sure there will be spaces available when you arrive — many airports now post that information online.

— Watch the weather. Even if skies are clear at home, there could be storms at your flight’s destination or along your road route. Have a backup route.

— Avoid checking bags. About one in every 170 checked bags was lost, damaged or stolen in May, the latest month for which government figures are available, but as the Seattle airport outage shows, stuff happens. Pack everything you need in a carry-on bag — after checking your airline’s size limits — and you will also avoid waiting at the baggage carousel after you arrive.

— Consider travel insurance, especially if it’s an expensive trip.

— Be nice. Flight cancellations and bumper-to-bumper traffic are frustrating, but you won’t be the only one who is stuck. Customer-service agents are busy during peak travel periods, so it’s important to be patient and respectful while they try to help you.

(AP)