The Chiefs might have already faced their biggest challenge before their game against the Broncos —leaving Kansas City.

Just before their planned departure on Saturday, the Chiefs’ team aircraft was stuck at the Kansas City International Airport (MCI) for almost four hours because of dangerous weather conditions in the vicinity.

The airport was forced to shut down the airfield for about two hours after airport officials said MCI was dealing with “rapid ice accumulation” while the Kansas City area

According to KMBC, officials warned that any travel in the area could be impossible on Sunday.

The Chiefs were set to depart for Denver at approximately 2:45 p.m. ET on Saturday but did not leave the runway until roughly 6:20 p.m., per NFL Network’s Ian Rapoport.

According to Fox 4 Kansas City, the de-icing machine at MCI was not working, causing delays for multiple flights at the airport.

The Kansas City Star reported that the Chiefs had plans to leave earlier on Saturday, but their team plane dealt with mechanical issues.

The Chiefs are scheduled to face the Broncos at 4:25 p.m. on Sunday in the regular season finale.

As the Chiefs look to avoid their second loss of the season, Denver is attempting a final postseason push.

The Broncos can clinch a spot with a win or if the Dolphins and Bengals both lose or tie.