Dense fog wreaked havoc on travelers inside both Chicago international airports — O'Hare and Midway — early Christmas Eve, as over 50 flights were grounded, leaving travelers stuck for the holidays. 

On Sunday, the National Weather Service issued a dense fog advisory for the entire Chicago area that initially expired at 9 a.m., but was later extended to 12 p.m. as heavy fog lingered.

At Midway alone, there have been around 50 cancelations so far, with increasing delays as the FAA issued a ground stop until 10:30 a.m., after travel was put on hold late Saturday night. 

Meanwhile, O'Hare airport has reported only 15 canceled flights with minimal delays. 

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A spokesperson for Southwest Airlines told Fox News Digital that they were working with travelers and working to get the situation resolved.

"We’re working with our customers whose travel is impacted by fog at Chicago Midway that began Saturday night and prevented inbound aircraft from landing, forcing some diversions and subsequent flight cancelations. With visibility remaining below required operational minimums throughout the night and continuing this morning, we’ve modified our planned start for today (Sunday) at Chicago Midway." Southwest Airlines said. "We have all-hands on deck as our employees are working to quickly take care of our customers and accommodate them on alternative flights."

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Southwest Airlines added that Chicago Midway is their fourth-busiest airport operation, with more than 200 departures a day scheduled over the holiday weekend.

"As a result of the fog at Midway, we have canceled approximately 70 flights for Sunday (less than 1% of our total flights of 4242 system-wide), which are mostly originating and morning flights from Midway. We are now operating the remainder of our schedule, but we continue to experience cancelations and delays as our operation recovers," Southwest said. 

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On top of weather delays, a user on X, formerly known as Twitter, posted that pro-Palestinian protesters had shut down the entrance to O'Hare Airport early Christmas Eve morning.