Millions of Americans in the Northeast, including New York City, are facing potential tornadoes and severe flooding as strong storms sweep through the region. Weather authorities issued several warnings, with flash flood alerts and travel advisories affecting various areas. Heavy rain is expected to cause flash flooding, particularly in urban areas where streets nearly turned into rivers following recent downpours. The National Weather Service has warned of damaging winds and hail accompanying the storms, and residents are advised to be cautious as multiple rounds of storms continue. With over 38 million people under flood threats, the situation is serious, and communities are urged to stay informed and prepared.