• By midday Monday, fewer than 1,000 flights were delayed in the U.S.
• Earlier in the weekend, airlines had canceled hundreds of flights while more than 10,000 were delayed.
• Demand was expected to spike over the long weekend.

U.S. airline delays eased on Monday as weather improved, a relief for travelers and airlines as the July Fourth holiday weekend comes to an end.

As of Monday afternoon, about 1,200 U.S. flights were delayed and 183 were canceled, down from nearly 4,700 delays and more than 300 cancellations a day earlier, according to flight-tracking site FlightAware.

This year through July 3, 2.8% of the more than 4.1 million flights scheduled by U.S. airlines were canceled, up from 2.1% of the more than 4.74 million flights scheduled in the same period, according to FlightAware. And so far this year, 20.2% of flights were delayed, up from 16.7%.

About a fifth of U.S. airlines' flights were delayed and 2.8% canceled, up from 2.1% canceled over the same period of 2019.

The weekend was key for airlines as executives expected a surge of travelers after more than two years of the Covid-19 pandemic. Passengers shelled out more for tickets as fares surpassed 2019 levels.

Industry staffing shortages, many the result of buyouts that airlines urged workers to take during the pandemic, have exacerbated routine challenges like bad weather.

U.S. airline executives will begin detailing their summer performances and providing updated outlooks for the year in quarterly reports starting midmonth. A big question is what happens after the summer-travel peak fades, as many children in the U.S. go back to school in August.

Airlines spent the last few weeks focusing on limiting summer travel disruptions. Delta Air Lines, JetBlue Airways, Southwest Airlines, United Airlines and others have trimmed their schedules to give themselves more room to recover when things go wrong, such as when thunderstorms hit major airline hubs over the weekend.

Airlines and federal transportation officials have pointed fingers at one another in recent days over the cause of the flight disruptions. Airlines blamed air traffic control for lengthy delays, while the FAA and Transportation Secretary Pete Buttigieg lashed out at airlines for letting go of workers during the pandemic, despite billions in federal aid.

Buttigieg on Saturday said one of his own flights was canceled.

"The complexity of modern aviation requires everything to work in concert," said Matt Colbert, who previously managed operations and strategies at several U.S. carriers and is the founder of consulting firm Empire Aviation Services.

Delta took the unusual step of allowing travelers to change their flights outside of the peak July 1-4 period if they can fly through July 8, without paying a difference in fare, in hopes customers could avoid some of the disruptions on the busiest days. Envoy Air, a regional carrier owned by American Airlines, offered pilots triple pay to pick up extra shifts in July, CNBC reported last month.

"Bring patience," Colbert said. "The people working on the other side of the counter are frustrated, too."

European travel has become chaotic with passengers at some of the biggest hubs facing long lines and baggage delays as the industry faces staffing issues and a surge in demand.

Scandinavian airline SAS on Monday said it would be forced to cancel half of its flights after pay talks with pilots' union representatives broke down, setting off a strike. Meanwhile, the chief operating officer of low-cost airline easyJet resigned after recent waves of flight cancellations.