Group 1 - A severe winter storm has impacted 21 states in the U.S., leading to a state of emergency and affecting over 28,500 flights [1] - As of the afternoon of the 25th, 10,485 flights have been canceled nationwide, with Washington Reagan National Airport experiencing nearly a 100% cancellation rate and New York LaGuardia Airport over 90% [1] - The National Weather Service forecasts that over 160 million Americans will be affected by this storm, which includes heavy snowfall, sleet, freezing rain, and extreme cold weather [1]