Southwest is blaming air-traffic control and weather-related challenges for more than 1,800 cancellations.

By: KDKA-TV’s Lindsay Ward , Royce Jones and Briana Smith

PITTSBURGH (KDKA) — Airline passengers across the country are waking up worried about their flights after one of the largest airlines canceled or delayed more than 2,000 flights over the weekend.

More were canceled Monday at Pittsburgh International Airport, including flights to Fort Myers and Las Vegas in the morning.

Staffing shortages are one reason for the cancellations, with long lines growing at numerous airports, including Laguardia, Denver and Dallas — all big airports that typically have thousands of travelers.

Southwest is blaming air traffic control and weather-related challenges for more than 1,800 cancellations.

The company is also saying that they’re operating fewer flights than it did pre-pandemic, which makes it harder to reschedule passengers.

As for staffing shortages, the FAA says that ended on Friday, but according to CBS News sources, the company’s staffing problems led to many flights being grounded over the weekend.

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On Saturday, more than 800 flights were canceled. On Sunday, more than 1,000 more were canceled, with more than 1,000 delays also being reported each day.

One Beaver resident missed her relative’s wedding because of the cancellations.

“We were there for almost 12 hours. That was a waste of my time and disheartening,” said Diane Wagner.

Wagner was headed to North Carolina on Friday for a wedding until her flight got canceled.

Her flight was rebooked for Saturday morning, but then it was canceled again after she landed in Nashville.

“They said, ‘there’s nothing we can do to get you to Durham, North Carolina,’ where we were going. ‘So you’ll have to wait here all day and we’ll send you back about 8:45 tonight,'” said Wagner.

Southwest has apologized for the massive travel disruption, saying it was trying to get people home quickly and safely.

“We missed the wedding. We got pictures. That’s all. Missing family we haven’t seen since the beginning of the pandemic. So that was hard,” said Wagner.

Wagner says she doesn’t believe air traffic control issues and the weather weren’t the only problem.

“When we looked at the other airlines, we saw them flying out so it’s hard to believe. I think they need more people,” said Wagner.

Wagner didn’t make the wedding and only received a $200 refund.

“I kind of felt like they could have done a little bit more even as far as talking to us instead of sending us a text or an email. At one point, they told us to stand in line. The line was 2 hours long,” Wagner said.

But she says she would give the airlines another chance, hoping for a better experience.

There has also been speculation about a pilot walkout after Southwest issued a vaccine mandate for employees last week. The Southwest Airlines Pilot Association says that’s not the case.

WATCH: KDKA’s Royce Jones Reports

Another traveler KDKA spoke with said the travel disruption turned what was supposed to be the perfect vacation into a nightmare.

Jennifer MacNeil said, “We’re down here and we’re struggling so bad. I’ve been on the phone crying, trying to get us somewhere. He’s actually been crying,” she said referring to her boyfriend, Joshua Schuffert, who was also on the trip.

The Orlando, Florida, trip with family and friends was supposed to last from Oct. 1-8. When the couple went to Orlando International Airport for their flight back home on Friday, it was delayed and canceled soon after.

MacNeil told KDKA the airline blamed the issues on air traffic control and weather. But said, “We’ve been in several parts of Florida this week. The weather was great.”

The very next day, their flight was delayed again for the same reasons.

When the time came to board, Schuffert said he was put on the plane, but MacNeil, her daughter and mother were held up with a reservation issue, even though some of their luggage had already been whisked away and placed on the belt.

So the couple booked the next available flight, which was Monday. That also ended up delayed.

Southwest released a statement Monday afternoon, saying:

“Southwest Airlines extends a tremendous apology to our Customers and Employees for the flight cancellations and delays which occurred over the weekend and on Monday.

“On Friday evening, the airline ended the day with numerous cancellations, primarily created by weather and other external constraints, which left aircraft and Crews out of pre-planned positions to operate our schedule on Saturday. Unfortunately, the out-of-place aircraft and continued strain on our Crew resources created additional cancelations across our point-to-point network that cascaded throughout the weekend and into Monday.

“While we do not have specific airport numbers to share, Southwest Teams have been working diligently to restore stability to the network, and we are experiencing less disruptions on Monday. We hope to restore our full schedule as soon as possible. As a note, the operational challenges were not a result of Southwest Employee demonstrations, as some outlets are reporting.

“To every Customer that experienced a cancellation or delay, Southwest offers our sincerest regret regarding disrupted travel plans, and we look forward to a future opportunity to demonstrate our safe, reliable, friendly, and legendary Southwest Hospitality – something that Customers should always expect from Southwest Airlines.

“If Customers require assistance from Southwest, they can utilize one of the airline’s self-service options for convenience or Contact Us via one of the methods listed on Southwest.com.”