Over 800,000 people in the US lost power due to a huge winter storm hitting eastern states. By 10:18 am EST Sunday, Tennessee faced over 300,000 outages. Mississippi, Texas, and Louisiana each had more than 100,000 outages. Kentucky, Georgia, North Carolina, and Alabama were also affected. The US Department of Energy (DOE) acted fast, issuing emergency orders to keep power grids stable. On Saturday, the DOE allowed Texas' Electric Reliability Council to use backup power at data centers and other key sites. On Sunday, similar authorization was given to PJM Interconnection to run special resources in the mid-Atlantic, even skipping some state and environmental rules. This harsh winter system brings snow, sleet, freezing rain, and biting cold across eastern two-thirds of the country through the week. President Donald Trump called the storms “historic” and declared federal disaster help for 12 states, including South Carolina, Virginia, and Tennessee. He urged people to “Stay Safe, and Stay Warm.” Seventeen states plus Washington D.C. declared weather emergencies as cold grips large areas. Department of Homeland Security Secretary Kristi Noem warned, “It’s going to be very, very cold,” and advised people to stockpile fuel and food. The National Weather Service warned of heavy ice in the Southeast with possible “crippling to locally catastrophic impacts.” Record cold and wind chills were forecast for the Great Plains by Monday. Travel was heavily impacted with 10,100 flights canceled Sunday after 4,000 cancellations Saturday. Airlines like Delta, JetBlue, and United reshuffled schedules and added cancellations mainly in the hardest-hit regions. Delta sent cold-weather experts to southern airports for fast de-icing and baggage help. Electric utilities prepared for big challenges. Dominion Energy said the storm might be one of the worst in its Virginia area, home to many data centers.