As slow-moving storms continue to develop across a flood-weary East Coast, cities including Washington, Baltimore, Philadelphia, and New York City are facing significant flood threats. The National Weather Service has issued warnings, indicating that extreme rainfall is likely to cause flash flooding, affecting travel and safety for millions. Areas that have already been hard-hit are bracing for more downpours, and the severe weather may linger into the coming week. With approximately 14 million people at risk, states are advised to prepare for potential disaster as conditions deteriorate with each thunderstorm that rolls through.