Air travellers could breathe a little easier on Monday, as a break in stormy weather and lighter schedules a day before the July 4 holiday helped airlines keep more flights moving on time.

By late morning on the East Coast, fewer than 100 US flights had been cancelled, although 1,000 were late, according to FlightAware.

United Airlines, the worst-performing US carrier for more than a week, laid out steps to improve, including reducing flights at its hub airport in Newark, New Jersey.

CEO Scott Kirby said over the weekend that United is working with regional authorities to get more gates at the airport, but the airline will need to reduce its schedule in Newark to have more of a buffer, especially during thunderstorm season.

Kirby continued to place much of the blame on the Federal Aviation Administration, which reduced the number of flights in and out of Newark a week ago.

That caused United to cancel flights and left planes and crews stranded out of position.

Nearly 2.7 million people per day have been streaming through airport checkpoints since Thursday, including 2.88 million on Friday, the highest number ever recorded by the Transportation Security Administration.

The Federal Aviation Administration expected about 36,500 flights on Monday and fewer than 32,000 Tuesday, then a jump to nearly 50,000 flights Wednesday, when more holiday revellers will return home.