BALTIMORE (WJZ) — Mass flight delays and cancellations continued nationwide on Monday during what’s widely known as the busiest time of year for air travel.

More than 4,400 delays were reported for flights into, out of or within the U.S., according to the flight-tracking website Flight Aware, which also reported over 1,100 cancellations for similar flights.

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The delays and canceled flights were attributed in some cases to disruptions resulting from winter weather and COVID-19.

Twelve cancellations and 129 delays were reported among flights in and out of BWI Thurgood Marshall Airport on Monday, according to Flight Aware.

In statements to WJZ, Alaska Airlines, Southwest Airlines and some Delta hubs said winter weather was responsible for some of those delayed and canceled flights.

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American Airlines and Delta were among the carriers that acknowledged COVID-19 cases among staff led to cancellations and disruptions.

Delta confirmed upwards of 200 of its 4,166 flights were canceled Monday. That’s after the airline canceled 374 of its 4,155 flights on Sunday.

A Southwest Airlines spokesperson said weather was to blame for the cancellations of roughly 50 of its more than 3,600 flights. The spokesperson said the airline said it has not seen any disruptions due to COVID-19.

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The Transportation Security Administration recommends checking your flight status ahead of time and arriving at the airport about two hours early.

Cristina Mendez