A union representing IRS workers in Kansas City was preparing for the layoff of potentially hundreds of probationary employees.

Union president Shannon Ellis said exact numbers are still being determined, but that there are around 1,000 or more probationary employees on campus as of Friday morning.

On a day when dangerously cold weather forced the Internal Revenue Service to close its downtown processing center, hundreds of probationary employees are on notice that their jobs are likely going away.

While tax season ramps up, the Trump administration’s wave of federal employee layoffs is expected to hit the IRS offices in Kansas City this week, according to one union leader. Workers with less tenure at the already-understaffed location are likely to be most affected.