Southwest Airlines has canceled more than 500 weekend flights and delayed more than 2,500 others, the continuation of a rough month for the nation's largest domestic carrier and its passengers.
The operational woes come amid a spike in flight attendant sick calls, but the airline says bad weather across the country is to blame.
Southwest canceled 287 Saturday flights, or 8% of its flights, as of 5:30 p.m. ET, after canceling 254 Friday flights, or 6% percent of its flights, according to flight tracker FlightAware. It had the most cancellations of any U.S. carrier, in total and as a percentage of flights, each day.
Tardy flights are a big issue, too: Southwest delayed nearly 1,600 Friday flights, or 43% of its flights, more than any U.S. airline, and so far Saturday has delayed 960 flights, or 28% of its flights, according to FlightAware.
The cancellations and delays come a week after Southwest canceled or delayed hundreds of flights due to two separate technology issues and a week after American Airlines struggled with operational woes during the busy Father's Day travel weekend and said it would proactively cancel nearly 1,000 July flights to give it more breathing room when weather and other issues crop up.
Why are Southwest flights canceled today
Southwest spokeswoman Alyssa Foster told USA TODAY on Saturday that the airline proactively canceled 150 flights "due to widespread thunderstorms expect across arts of the nation.'' She cited cities including Denver, Orlando, Chicago and St. Louis.
"These proactive cancellations will allow us to minimize delays and diversions due to the storms and probable ATC (air traffic control) initiatives,'' she said in a statement.
On Friday, Southwest spokesman Dan Landson attributed Friday's cancellations to summer storms.
"To proactively manage our operation, we implemented a scheduled reduction ahead of expected storms and probable air traffic control initiatives,'' he said in a statement.
"Excessive'' flight attendant sick calls a factor?
On Friday, Southwest implemented its emergency sick call procedures for the second time in a week due to a spike in flight attendants calling in sick, a level the airline deems "excessive.''
"We simply cannot manage the operation with the number of sick calls we are taking and quickly using reserves,'' Sonya Lacore, Southwest's vice president of inflight operations, said in a memo to flight attendants viewed by USA TODAY.
Lacore apologized to employees for the extra steps the emergency call in procedure require for those who are ill but said it is required to "keep the operation running.''
"I also recognize many of you are tired and our intent in moving in this direction is not to make this a punishment,'' Lacore said. "We are simply doing what is required to keep our planes flying and protect both our operation and flight attendants already at work.''
Asked about the implementation of the emergency sick call procedures, Southwest's Foster attributed it to the airline's "irregular operations'' caused by "large, summer thunderstorms.''
"It is not uncommon for Southwest to proactively implement this policy in peak travel and/or holiday timeframes to protect the operation and our working crews to ensure appropriate staffing,'' Foster said via email.
What happens if Southwest cancels my flight?
Travelers whose flights are canceled are being rebooked on other flights. But some travelers are finding the next flight isn't always the same day given the busy summer travel season.
And plenty of travelers are finding it hard to reach the airline, a universal problem for passengers this summer.
Can I get a refund if an airline cancels my flight?
Passengers whose flights are canceled or significantly delayed are eligible for a refund per U.S. Department of Transportation rules, even if the airline has already rebooked them.
The problem with opting for a refund during peak travel times if your trip is a must and you're on a budget: Finding a last-minute flight on another airline won't be easy or cheap.
This article originally appeared on USA Today