Kathleen Miller was sleeping when the text from Southwest Airlines arrived at 1:18 a.m. Sunday.
Her 7:30 a.m. flight from Phoenix to Dallas was canceled.
The Pennsylvania woman didn't see the text until she was at the airport, where Southwest representatives directed her to a snaking rebooking line next to the ticker counters.
She stood in line for 45 minutes and left with a less-than-satisfactory rebooking option: a Tuesday flight.
"Luckily we have relatives here in the city,'' Miller said.
Stranded Southwest passengers across the country are struggling with a second day of mass flight cancellations by the nation's largest domestic airline.
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Southwest has canceled 1,018 Sunday flights as of 2 p.m. ET, according to flight tracker FlightAware. That's 28% of the the airline's scheduled flights and the highest of any U.S. airline by a wide margin.
American Airlines has canceled 63 flights, or 2% of its operation, while Spirit Airlines canceled 32 flights, or 4% of its flights, according to FlightAware.
The U.S. airports with the the heaviest flight cancellations for departures and arrivals Sunday are all big Southwest “hubs,” even if the airline doesn't refer to them as such: Denver, Baltimore, Dallas Love Field, Las Vegas and Chicago Midway.
Southwest's Sunday cancellation are on top of 808 cancellations on Saturday, or nearly one in four flights. This during a busy travel weekend given a federal holiday on Monday.
The airline blamed the problem on air traffic control issues and weather. In a statement Saturday the airline expressed optimism its operations on Sunday would improve, not worsen.
"We experienced significant impact in the Florida airports yesterday (Friday) evening after an FAA-imposed air traffic management program was implemented due to weather and resulted in a large number of cancellations. We are working hard behind the scenes to minimize challenges and fully recover the operation as we take care of displaced crews and customers as quickly as possible. We will continue to reset our network today and hope to return to close to normal operations as we move into Sunday.''
ATC issues and disruptive weather have resulted in a high volume of cancellations throughout the weekend while we work to recover our operation. We appreciate your patience as we accommodate affected Customers, and Customer Service wait times are longer than usual. (1/2) pic.twitter.com/o1scQJ5lLb
— Southwest Airlines (@SouthwestAir) October 9, 2021
On Sunday, the FAA responded to Southwest's statements blaming air traffic control issues and weather — without naming the airline — and said those issues were limited to Friday afternoon.
“No FAA air traffic staffing shortages have been reported since Friday,” Steve Kulm, FAA spokesperson, said in a statement. "Flight delays and cancellations occurred for a few hours Friday afternoon due to widespread severe weather, military training, and limited staffing in one area of the Jacksonville Air Route Traffic Control Center.''
“Some airlines continue to experience scheduling challenges due to aircraft and crews being out of place,” the statement continued. “Please contact the airlines for details about current flight schedules.”
Southwest has not commented on speculation about other possible causes, including opposition to a vaccine mandate the airline announced a week ago following the federal vaccine mandate announced in mid-September by President Joe Biden.
“Southwest Airlines must join our industry peers in complying with the federal government’s COVID-19 vaccination directive,” Southwest CEO Gary Kelly said on Oct. 4.
Casey Murray, president of the Southwest Airlines Pilots Association (SWAPA) blamed the flight woes on staffing and a “poorly run operation.” He said the rate of pilots calling in sick has not spiked this weekend. He said nearly three out of four pilots working Saturday had trips rerouted due to the flight woes.
In a statement posted to its website Saturday, the union said: "SWAPA is aware of operational difficulties affecting Southwest Airlines today due to a number of issues, but we can say with confidence that our pilots are not participating in any official or unofficial job actions.
"Our pilots will continue to overcome SWA management’s poor planning, as well as any external operational challenges, and remain the most productive pilots in the world. They will continue to be focused on their highest priority — safety.''
The fall travel troubles for Southwest follow a rough summer for the airline's operation. The airline's executives have repeatedly said their top priority is getting Southwest's operation back on track. The airline is hiring thousands of workers to help with a staffing shortage.
►'We're not out of the woods yet': Southwest admits operational struggles
This article originally appeared on USA TODAY: Southwest Airlines flight cancellations strand customers around US