Hurricane Sandy closed in on the United States early Sunday as coastal communities along the East Coast scrambled to prepare for torrential rains, high winds, major flooding, power outages and heavy snow a week before the presidential election. Forecasters said Sandy has all the ingredients to transform into a “super storm” as it merges with an Arctic jet stream, which could make the storm unlike anything seen over the eastern United States in decades.

“We’re looking at impact of greater than 50 to 60 million people,” said Louis Uccellini, head of environmental prediction for the National Oceanic and Atmospheric Administration. States of emergency were declared in eight states from North Carolina to Massachusetts, as well as Washington, D.C., as Sandy made its way north after killing 41 people in the Caribbean. Governors of states in Sandy’s path ordered mandatory evacuations of vulnerable areas. New York City officials also discussed whether to shut the subway system on Sunday evening in advance of the storm.