The heavy rainfall poses a life-threatening risk of flash flooding, particularly in urban areas like New York City and Long Island. Infrastructure, including roads and power lines, is at risk of damage, with over 280,000 customers already experiencing power outages. Basement apartments are especially vulnerable, and residents are advised to evacuate if water levels rise. The storms have also disrupted travel, with flight delays and cancellations reported at major airports in the region. The risk of flash flooding extends to major cities such as Boston, Philadelphia, and Washington, D.C., potentially affecting millions of residents.