Core Viewpoint - A severe winter storm in the northeastern United States has led to the cancellation and delay of over 8,000 flights, prompting airlines to increase operations on Tuesday, although thousands of flights remain affected [1] Group 1: Flight Operations - Airlines, including United Airlines, are planning to strengthen operations on Tuesday in response to the storm, but they warn that the situation remains serious [1] - As of Tuesday afternoon, it is expected that 7% of U.S. flights will be canceled, a decrease from over 19% on Monday [1] - The typical cancellation rate for domestic flights in the U.S. is around 1% per day [1] Group 2: Impact of the Storm - The winter storm has caused road closures and school cancellations in parts of the northeastern U.S. [1]