On Sunday, TSA spokesperson Michael Bilello said 7.7 percent of the agency’s employees had an unscheduled absence today, compared with 5.6 percent on Saturday and 3.2 percent a year ago.
According to Bilello, 99.9 percent of airline passengers across the U.S. waited less than 30 minutes at their checkpoints.
Official wait time data for Sunday wasn't immediately available.
More than 51,000 airport security screeners are required to work through the government shutdown --despite the agency's inability to provide them their regular pay -- until it secures congressional funding from lawmakers in Washington.
In addition to missing a regular payday, thousands of TSA employees are dealing with winter weather stretching from the Midwest to the East Coast.
Parts of Missouri, Iowa and Illinois received more than a foot of snow by Sunday morning. With at least 10 inches of snow in St. Louis so far, this is the biggest snow storm the city has seen in 5 years.
Five inches of snow in New Jersey and ice-covered roads as far south as North Carolina made for dangerous driving conditions in other parts of the country.
In an apparent effort to raise the spirits of those tasked with keep the country's airports safe, TSA Administrator David Pekoske announced on Friday that his uniformed screening officers would soon receive a one-time bonus of $500 "in recognition of their hard work during yet another busy holiday travel season, maintaining the highest of security standards during an extraordinary period."
That extraordinary period has seen an increasing number of airport screeners calling out of work, even before the government shutdown postponed paychecks for the first time on Friday, sparking fears of long lines and staffing shortages as the shutdown continues.
The National Air Traffic Controllers Association is currently suing the Trump administration on behalf of the thousands of controllers that have not been paid during the record-breaking shutdown.
The suit, filed in federal court in Washington, D.C., claims the administration has violated the Fifth Amendment by depriving workers of wages without due process and violated fair labor regulations by not at least paying minimum wage to air traffic controllers and others who are required to work during the government shutdown. The suit also claims the FAA didn't promptly pay overtime to union members, an oversight the union said is also in violation of regulations.
While the shutdown drags on, maintenance, inspection, training and modernization programs have also been deferred.
"While we are doing the day-to-day tasks there's a lot of things that are falling through the cracks," Portland International Airport tower controller Richard Kennington told ABC News. "There's a lot of insidious stuff that the flying public doesn't see that's not happening."