In the (very) recent news, due to the violent January 6 events at the Capitol, the Speaker of the House threatened impeachment if the President doesn’t resign soon.
According to her, "the President is unstable and needs to be removed from Office" (source)
“Today, following the president’s dangerous and seditious acts, Republicans in Congress need to follow that example and call on Trump to depart his office — immediately,” she wrote. “If the president does not leave office imminently and willingly, the Congress will proceed with our action.” (source)
An "impeachment" is usually a long process. How can this be put in place before January 20, in less than 2 weeks?